|Table of Contents|
Table of Contents
Key to the orders
BEING DESCRIPTIONS OF THE SEED PLANTS GROWING NATURALLY
IN FLORIDA, ALABAMA. MISSISSIPPI. EASTERN LOUISIANA.
TENNESSEE. NORTH CAROLINA, SOUTH CAROLINA
JOHN KUNKEL SMALL
THE UNIVERSITY OF NORTH CAROLINA PRESS
COPYRIGHT 1933 BY
THE UNIVERSITY OF NORTH CAROLITNA PRESS
Manufactured in the United States of America
P r e f a c e .............................................................................................................................................................. iv v ii
Introduction .............................................. ix-xiii
Key to the Orders ............................................. xv-xxii
D escrip tiv e F lora ...................................................................................................................................... 1- 14 9 9
Appendix1500-1502 ........................................................................................................................................................... 1500-1502
Genera and species published in this Flora ................................................................. 1503-1509
Table of Orders and Families ........................................ ............... 1510-1512
Index ....................................................... 1513-1554
This volume is designed to record and describe the species of native
and naturalized flowering plants known by the author to grow naturally
in the southeastern United States south of the northern boundaries of
North Carolina and Tennessee and east of the Mississippi River. The
species are grouped in genera, families, and orders, and are so arranged
and described that they may be identified by means of the analytical keys
and synopses given under each group, mainly by a study of the morphol-
ogy of the flowers and the fruits.
The arrangement of the natural plant families is essentially that of
Engler and Prantl, Die Natiirlichen Pflanzenfamilien, although in a few
cases modifications of the sequence there adopted seemed to be desirable.
The descriptive matter has been made very short, except in special cases.
In order to facilitate the tracing and determination of genera and species,
a drawing showing a flower and its gross morphology and a fruit, of the
first species under each genus is given. The illustrations are not made
to a scale, but the sizes of some of the parts are usually given in the de-
scriptive matter. The drawings were made by Miss Mary E. Eaton, with
the exception of those of the grasses, which were made by Mrs. Agnes
Chase,' and those of Carex which were made by Mr. H. Creutzberg, through
the interest of Mr. K. K. Mackenzie.
In the matter of the interpretation of species and genera what has
seemed to the author a balanced course has been followed-traditional
"lumping" and modern "splitting" have not influenced the treatments of
the various groups. Complex genera have been divided into more natural
groups, both for convenience of study and also in order to make the gen-
era, as far as possible, correspond in rank to the great majority of groups
of species now recognized as genera by most present-day botanists.
Species have been interpreted in the broader sense; minor variations of
species, "varieties" or "subspecies" have not been considered to any great
extent. "Subvarieties", "forms", "subforms" have not been considered
The names adopted for species and genera in this volume are those
which to the best of the author's knowledge, were first applied to each,
accompanied or supported by an adequate description, and in the case of
genera by specific references, from the time (1753) when binomial desig-
1 The drawings for the grasses were made with the understanding that they
were to be reduced to 1 inch square, allowance being made for such reduction.
Coarseness of the illustrations, if any, is due to the fact that the drawings were
not reduced in engraving.
nation of species was definitely introduced into biological nomenclature,
unless preoccupied for another species or genus.2
During the preparation of this manual, numerous botanists, natural-
ists, and collectors helped continuously by the contribution of specimens
and of information relating to the vegetation and its distribution, in short,
doing much to help to make this volume complete.
Botanists as indicated below kindly prepared the text for several
plant-families printed in this volume: POACEAE, by Dr. A. S. Hitchcock;
POLEMONIACEAE, by Dr. E. T. Wherry; RHINANTHACEAE, by Dr. F. W.
Pennell; PINGUICULACEAE, by Dr. J. H. Barnhart; LORANTHACEAE, by Dr.
William Trelease. The text for certain genera was prepared by the follow-
ing botanists: Iris, Vincetoxicum, Odontostephawa, Scutellaria, Laciniaria,
Zinnia, Melanthera, Pterophyton, Cosmos, Emilia, by Mr. E. J. Alexander;
'Philadelphus, by Mr. C. D. Beadle; Crataegus, by Mr. Ivar Tidestrom;
Tilia, by Mr. B. F. Bush; Physalis, Acanthoxanthium, Xanthium, by the
late Dr. P. A. Rydberg; Carex, Solidago, by Mr. K. K. Mackenzie; Rud-
beckia, by Mr. C. L. Boynton and Mr. C. D. Beadle; Helianthus, by Mr.
E. E. Watson; Coreopsis, by Mr. F. E. Boynton; Bidens, by Dr. Karl
M. Wiegand. The following genera were revised: Viola, Aster, by Mr.
E. J. Alexander. Assistance is preparing the text of Philotria and
of Trillium was furnished by Dr. Harold St. John and Mr. Donald C.
Help in many ways was given by my associates on the botanical staff
of the Garden. Among those who participated in intensive field-work of
the past two decades were Mr. Charles A. Mosier, the late Captai iPaul A.
Matthaus, and Mr. John B. DeWinkeler. Both the galley and the page
proof have been read by Dr. Edgar T. Wherry, who also supplied the
provincial distribution of the species, checked many of the geographic
ranges, and furnished data as to habitats and soils. The galley proof was
read in whole or in part by Mr. Kenneth K. Mackenzie, Dr. N. L. Britton,
Dr. Roland M. Harper, Mr. Edward J. Alexander, and Miss Bertha Picker-
ing, while each contributor of generic or family treatments, as indicated in
the text, read the proofs of'these.
The author is indebted to Dr. John H. Barnhart for advice and
information on many botanical and bibliographic questions that arose
throughout the years of preparation of the manuscript and the reading
2 The manuscript of the grasses (POACEAE) was completed several years
ago and was held in proof along with other parts of this work. It was there-
fore impracticable to bring the nomenclature into accord with the rules of
nomenclature which Dr. Hitchcock is now following. This statement also ap-
plies to the treatment of the figworts (RHINANTHACEAE) by Dr. Pennell, and to
the treatments of several other families and genera by others, for which credit is
of the proof and to Mr. E. J. Alexander for cooperation in studies on
many genera and species.
The completion of the manuscript was made possible, in part, by the
cooperation of the Board of Managers of The New York Botanical Garden.
The publication was made possible, in part, by the interest of the late
Mr. Charles Deering.
The numerous specimens, which the investigations connected with this
work have brought to the author during a period of thirty-five years, along
with much botanical information, have been incorporated in the herbarium,
the museums, and the records of the Garden.
JOHN K. SMALL.
THE NEW YORK BOTANICAL GARDEN,
BRONX PARK, NEW YORK, N. Y.
November 30, 1933
This manual supplants, in part, the Flora of the Southeastern United
States published by the author in 1903 (second edition 1913). That
volume recorded and described the flowering plants and pteridophyta3
known at that time to grow naturally in the southern United States east
of the one hundredth meridian of longitude. The complexity and magni-
tude of the flora in this area, resulting from its proximity to the tropics,
the intrusion of the northern highlands, and the extension of the Great
Plains and the deserts from the west, made it seem desirable to divide the
"Flora" into two parts. The result is the present volume and a proposed
volume to include the area west of the Mississippi River south of the same
degree of latitude and east of the western boundary of Texas. Thus
smaller volumes will result, and plants may be traced by the analytical
keys with greater ease, since fewer genera and species are usually involved.
The geographic area concerned represents one of the cradles of botany
on the American mainland, for on the coasts of the Gulf States early
Spanish expeditioners were necessarily, not by choice, brought into close
contact with the native vegetation. They left us printed records of the
uses made of various plants by the aborigines and by themselves for foods,
drinks, medicines, clothing, utensils, and fumitories. Their interest was
not wholly utilitarian, for some plants so impressed them, the cacti for
example, that they took them back to Europe and grew them there.
About a century after the discovery of America by Columbus, living
specimens of plants from the Atlantic coast began to find their way into
European botanic gardens. Explorations by plant collectors were soon
extended into the highlands and into the Florida peninsula. Later, col-
lectors were sent over from Europe and Americans were commissioned by
European patrons of botany to explore for plants. American residents
about this time began to publish the results of their studies. Today the
works on the flora are numerous.
The first American botanical garden in the northeast developed near
Philadelphia, Pennsylvania, in the middle part of the eighteenth century,
as a result of the plant-collecting activities of John Bartram. Here many
of the plants of the southeast were cultivated. In the second half of that
century the first botanical garden in the southeast grew about the home of
Thomas Walter on the Santee River north of Charleston, South Carolina.
Walter's association with this native flora crystallized into the first manual
of the plants of a more or less definite geographic area, under the title
Flora Caroliniana, in 1788. Interest in the native plants and in botany
increased and reached a culmination about the middle of the last century,
3 The pteridophyta are omitted from the present work.
in the publication of Chapman's Flora of the Southern United States, in
1860. Then, botanical activity waned in the South. Toward the end of
the last century, however, a revival took place in the southeastern states,
mainly through the activities of permanent and transient residents, of
plant collectors, and of botanists and naturalists who moved into the region
to fill professional positions.
In pioneer days with the horse and few trails, the sail-boat and un-
developed water-ways, botanical exploration was restricted to limited areas
and progressed slowly, consequently the botanical harvests were often scant.
Since the advent of the automobile, the motor-boat, and the construction
of a vast network of highways, canals, and improved waterways, largely
through virgin country, a vast territory, until recently inaccessible, has been
made to yield numerous botanical and horticultural treasures. As a con-
sequence, many additional species and not a few genera of all groups of
plants have been recorded for the area under consideration only since the
end of the last century.
The area extends over about twelve degrees of latitude. The southern
limit lies within less than a hundred miles of the Tropic of Cancer. The
northern limit is not very far north, but two mountain ranges, with a mul-
titude of peaks rising to between five and six thousand feet and several
to more than six thousand, furnish a cool climate representing a high lati-
tude through altitude. Intermediate altitudes (Piedmont and Appalachian
Plateau) supply still other elements for greater variety in the vegetation.
As compared with northeastern America there are one-third more species
in about one-fifth the area. Three main factors contribute to this con-
dition-latitude, geology, physiography.
The ancestors of our present plant-covering were subjected to both
major and minor earth disturbances, elevations and depressions and re-
arrangements of the land-mass. Submergences also destroyed vast areas
of coastwise vegetation several times. When the areas emerged from the
sea for the last time and the higher lands became more stable, the coastwise
areas were populated from both the plant refuges in the highlands and
those of continental and insular regions lyinglo the south. Whether" these
early floras were more extensive in kinds and density of population than
those of today we shall never know. The records of several different
floras are preserved in the sedimentary rocks, but they are naturally very
incomplete. Large areas of eroded materials of the very old geological
formations, often segregated into areas of different kinds of soil, such as
sand, clay, marl, loam, in the Coastal Plain and the Piedmont, very defi-
nitely contribute to the complexity of the flora. Then, in relatively recent
geologic time, came the advance of successive great ice-sheets from the
north as far south as New Jersey and Pennsylvania, with accompanying
cold, which killed the vegetation before their immediate front, while they
advanced, or drove the more distant plants southward. When the ice
receded to the north some plants at the south doubtless succumbed as the
temperature rose to a point beyond their endurance more rapidly than
they could migrate; while others accommodated themselves to the new
conditions, and traveled back to their former, more northern latitudes.
Thus our present plant population shows the results of invasions from
the north. On the other hand, peninsular Florida, and in a lesser degree
the more northern Gulf Coast, received many elements from the West
Indies near at hand, and from northern South America, carried over a
narrow ocean area by birds, winds, and currents. The physiographic struc-
ture. of the area involved furnishes a sliding scale, either from the boreal
to the tropical or vice versa, so that any plant which gains a foothold in
the area might find conditions suitable for its growth and maintenance.
The above remarks apply mainly to the eastern part of the area; here we
find a very dense plant population, specifically and generically considered.
In the western part there are less differences in elevation, and much simpler
geologic history; here there is sparser plant-population both in density and
There are many locally peculiar minor plant areas. For example,
capes, peninsulas, coastal sand-dunes, river-deltas, river-valleys or water-
sheds, swamps, marshes, plateaus, mountain-valleys, mountain ranges, and
mountain peaks, each harboring peculiar or endemic plants.
The accompanying map shows the territory included in the South-
eastern States and the Southcentral States. The Mississippi River divides
the area into approximate halves. Both areas are shown for convenience
in tracing the geographic distribution of the plants, and to show the rela-
tion of the floras of the two areas. These are closely related at the boun-
dary line, for they both naturally merge in the ancient delta of the Mis-
sissippi River or the present Coastal Plain part of the Mississippi water-
Following the description of each species, and separated by a dash
from it (or from synonyms or common names which may be introduced at
this point), the habitat, the province, and the geographic range are stated.
Habitat.-Not only are the physical features briefly characterized, but
in cases where it seems noteworthy, something is stated as to the chemical
nature of the soil, that is whether it is acid, neutral, or alkaline, whether
siliceous or calcareous. When the habitat is given as pinelands, the soil
may be inferred to be acid, except in southern Florida, where the pine-
woods cover limestone rocks and have more or less alkaline soil. Other-
wise, where no statement is made as to soil reaction, either no data are
available or else the plant appears to be indifferent to this factor.
Provinces.-Each species is here assigned to one or more physiographic
provinces. These are used instead of life-zones because the latter do not
A. Coastal Plain G. Ouachita
B. Piedmont H. Ozark
C. Blue Ridge I. Central Lowland
D. Appalachian Valley J. Great Plains
E. Appalachian K. Basin and Range
Plateaus L. Southern Rocky
P. Interior Low Mountains
really express very well the distributional relations of plants in our region.
Thus, in the east Gulf Coastal Plain, where the Lower Austral life-zone
should supposedly be represented, there occur many Transition and even
Canadian plants which have pushed southward, west of the Appalachian
mountains, in some past geological period and have persisted there. Again,
in the Blue Ridge, where on ascending a high mountain the theoretical
sequence should be Upper Austral-Transition-Canadian-Hudsonian,
one finds instead a mixture of Upper Austral and Transition plants on
the lower slopes, Canadian plants further up, but then instead of any-
thing more boreal, a mixture of plants characterizing the Upper Austral
of the Atlantic Coastal Plain mingled with many Transition shrubs and
Canadian trees at the summit. It has accordingly seemed best to refer the
plants only to the physiographic provinces in which they have been ob-
served to grow, and to leave the untangling of the complexities of life-
zone relations to other writers.
The physiographic province names used have been taken, with minor
modifications, from "Physiographic Divisions of the United States."4 The
boundaries of those lying within our limits are indicated on the accompany-
ing sketch map (figure 1), and certain points concerning their positions are
Interior Low Plateaus
Separated in some cases into "Atlantic" and
"Gulf" Coastal Plain, the division between these
extending from Macon, Ga., to Gainesville, Fla.
Alabama to New York; between the Coastal Plain
and the Blue Ridge and Appalachian provinces.
Often collectively referred to as "Appalachian
Includes E Canada; often divided into "Upland"
and "Coast," the division between these lying
roughly 30 miles inland.
Northern Alabama to Southern Illinois, Indiana,
The portion immediately surrounding Lakes Michi-
gan, Huron, and Erie is often separately referred
to as the Great Lakes Lowland.'
Texas to North Dakota.
Northern Arkansas to central Missouri.
Central Arkansas to eastern Oklahoma.
Western Texas to California and southern Oregon.
4 Nevin M. Fenneman, Ann. Assoc. Am. Geogr., 1917, reprinted 1921.
In addition, the following special groupings of provinces are often
"Coastal Plain and adj. provinces." Plants thus annotated appear
to reach their maximum development on the Coastal Plain, but also occur
northward and westward in the Piedmont, Appalachian Valley, Appa-
lachian Plateau, and other provinces which border the Coastal Plain.
"Various provinces, in Coastal Plain only N." These plants are not
known to grow in the Coastal Plain within our limits, although they may
be abundant in or even typical of that province further northward, as in
Va., Md., or N. J.
"Blue Ridge and more N Provinces." In this manner are designated
plants which reach their greatest development in regions north (and north-
west) of our limits, or in some cases in the Rocky Mountains.
As the states of Florida, Mississippi, and Louisiana lie essentially
within the Coastal Plain, plants limited to them have not required spe-
cial mention of province. Moreover, plants occurring "in salt-marshes
along the coast" or "on sand-dunes," are so obviously limited to the Coastal
Plain that statement of it has been omitted. It is of course realized that
the Coastal Plain is not an ecological unit, being divisible into a consider-
able number of areas with different soils and other features; however, in a
work of the scope of the present volume it is impracticable to go into
details in this respect, which must be left for the writers of local floras.
While every effort has been made to have these province-assignments
accurate, the data in the literature are often inadequate to decide the exact
range of given species, and errors which users of this work may discover
will be thankfully received.
Range.-Instead of following the usual plan of beginning range state-
ments at the northeast, we begin at the southeasternmost state within our
limits at which the plant is known to occur. When the starting-point lies
toward the eastern coast, the final state named is that lying furthest north-
east, as "Ga. to La., Minn., and Me." When, however, the start is made
far inland, the last state given is the southernmost in which the plant ap-
proaches the coast, as "Tenn. to Mo., Mich., N. Y., and Va." The pri-
mary reason for this method is that this manual covers southern plants,
and users are naturally most interested in the places where the plant
occurs in the south, hence it is convenient to have the southern limits
come first. There is, however, also a scientific significance to the plan, in
that the last great plant migration on this continent, resulting from the
climatic change connected with the retreat of the ice-sheets of the final
stage of the Glacial Period, consisted in a movement of plants from south
to north, of which the range as stated may give a rough picture.
J. K. S.
KEY TO THE ORDERS
Plants producing flowers and seeds. A seed contains an embryo consisting of a
short stem radiclee, caulicle, hypocotyl), one, two, or several rudimentry
leaves cotyledonss), and a terminal bud (plumule).
Carpel or pistil represented by a scale on the face of which the ovules are borne.
and on which the naked seeds mature. Class 1. GYMNOSPERMAE.
Carpel or pistil with a closed cavity within which the ovules are borne and the
seeds mature. Class 2. ANGIOSPERMAE.
Plants growing by single terminal bud or sometimes with adventitious buds, when with
pinnate leaves, circinate in bud.
Palm-like or fern-like plants. Leaves in a crown: blades pinnate. Flowers
in cones of approximate scales or on less modified leaves. Staminate
cone with scales bearing several pollen-sacs. Ovulate cone with two
or more ovules on each scale. Seed drupe-like or nut-like.
Order CYCADALES. 1
Shrubs or trees. Leaves scale-like, narrow, or needle-like, and often borne in
bundles. Flowers mainly monoecious, the cones of spirally imbricate
bracts or in Taxaceae the ovulate flowers often solitary. Seed borne in
a cone of dry or fleshy scales, or partly or wholly naked.-A group devel-
oped later and more highly organized than the CYCADALES.
Order PINALES. 2
Embryo with a single cotyledon, the early leaves alternate; blades, except in
Smilacaceac, parallel-veined: stem with a mass of cellular tissue through which
woody fibers are scattered: flower with the parts in threes or sixes.
Subclass 1. MIONOCOTYLEDONES.
Embryo usually with a pair of opposite cotyledones, the early leaves opposite:
blade net-veined: stem with central pith, enclosed in layers of wood which is
surrounded by bark: flower with the parts in fours or fives.
Subclass 2. DICOTYLEDONES.
Perianth rudimentary or degenerate, the members often bristles or mere scales,
not corolla-like, or wanting.
Flowers not in the axils of dry or chaffy bracts (scales or glumes).
Perianth of bristles or chaffy scales. Order PANDANALES. 13
Perianth fleshy or herbaceous, or wanting.
Fruit baccate: endosperm present. Order ARALES. 243
Fruit drupaceous: endosperm wanting. Order NAIADALES. 14
Flowers in the axils or dry or chaffy, usually imbricated, bracts (scales
or glumes). Order POALES. 29
Perianth of 2 distinct series, the inner series usually corolloid.
Gynoecium of distinct carpels. Order ALISMALES. 220
Gynoecium of united carpels.
Endosperm mealy. Order XYRIDALES. 250
Endosperm fleshy, horny or cartilaginous.
Ovary, and fruit, superior.
Herbs, or rarely shrubs or trees, with simple leaves: ovules
2-many in each cavity of the ovary, or solitary only in the
case of a few herbs.
Inflorescence not a fleshy spadix. Order LILIALES. 273
Inflorescence a fleshy spadix subtended by a spathe.
Order ARALES. 243
Trees or shrubs, with pinnately or palmately compound or lobed
leaf-blades: ovules solitary in each cavity of the ovary.
Order ARECALES. 236
Ovary, and fruit, wholly inferior or half-inferior.
Endosperm present and usually copious.
Flowers regular: androecium not reduced.
Order AMARYLLIDALES. 314
Flowers very irregular: androecium much reduced and modi-
fied. Order SCITAMINALES. 358
Flowers regular, monoecious or dioecious: aquatic plants.
Order HYDROCHARITALES. 20
Flowers irregular, perfect: terrestrial or epiphytic plants.
Order ORCHIDALES. 362
KEY TO THE ORDERS
Corolla wanting, except in the pistillate flowers of Juglans (Juglandaceae).
Calyx wanting, at least in the staminate flowers, except sometimes in
Flowers mainly perfect.
Seeds solitary in each carpel or in each cavity of the ovary:
Flowers spicate: styles wanting: stigmas sessile.
Order PIPERALES. 399
Flowers axillary: styles present.
Callitrichaceae in Order EUPHORBIALES. 804
Seeds numerous in each cavity of the ovary: endosperm wanting.
Podostemaceae in Order ROSALEs. 584
Flowers monoecious or dioecious. Order EUPHORBIALES. 774
Trees or shrubs: flowers monoecious or dioecious, or polygamous.
Leaves represented by appressed whorled scales: stems or branches
loosely jointed. Order CASUARINALES. 402
Leaves not appressed scales: stems or branches not loose jointed.
Fruit 1-seeded: seeds without tufts of hairs.
Ovules 1 or 2 in each cavity of the ovary: flowers not in heads.
Gynoecium 1-carpellary: stigma 1: ovule laterally attached
and amphitropous. Order LEITNERIALES. 407
Gynoecium 2-carpellary: stigmas 2: ovule erect and amphi-
tropous or pendulous and anatropous.
Pistillate flowers without a calyx: ovule erect and or-
thotropous. Order MYRICALES. 408
Pistillate flowers with a calyx: ovule pendulous and
Fruit a nut or an achene.
Corylaceae in Order FAGALES. 415
Fruit a drupe. Oleaceae in Order OLEALES. 1037
Leaf-blades compound: fruit a samara.
Oleaceae in Order OLEALES. 1037
Ovules many: flowers aggregated into dense heads.
Altingiaceae in Order ROSALES. 601
Fruit many-seeded: seeds each with a tuft of hairs.
Order SALICALES. 410
Calyx present at least in the staminate or in the perfect flowers.
Leaves represented by appressed whorled scales: branches loosely jointed.
Order CASUARINALES. 402
Leaves not appressed scales: branches not loosely jointed.
Flowers, at least the staminate, in aments, or ament-like spikes.
Leaf-blades simple: ovule pendulous and anatropous.
Pistillate flowers separate at maturity: fruit a nut or an
achene. Order FAGALES. 415
Pistillate flowers forming aggregate fruits: fruit drupe-like.
Artocarpaceae in Order URTICALES. 437
Leaf-blades pinnately compound: ovule erect and orthotropous.
Order JUGLANDALES. 403
Flowers, at least the staminate, not in aments.
Gynoecium of 1 or several and distinct carpels: stigma and
Style lateral and oblique.
Petiveriaceae in Order CHENOPODIALES. 485
Style, axile, erect.
Ovary neither enclosed nor seated in a hypanthium
or a calyx-tube.
Flowers not solitary in axils; land plants.
Filaments free and distinct.
Urticaceae in Order URTICALES. 431
Filaments adnate to the sepals or to the
calyx-tube. Order PROTEALES. 918
Flowers solitary in axils: aquatic plants.
Ceratophyllaceae in Order RANALES. 509
Ovary enclosed in or seated in a hypanthium or a
Stamens borne under the gynoecium.
Allioniaceae in Order CHENOPODIALES. 487
Stamens borne on the hypanthium or adnate to
the calyx-tube. Order THYMELEALES. 919
Stamens inserted below the ovary.
Families in Order RANALES. 583
KEY TO THE ORDERS
Stamens inserted on the edge of a cup-shaped hy-
panthium. Rosaceae in Order ROSALES. 604
Gynoecium of 2 or several united carpels: stigmas or styles
2 or several.
Ovary, by abortion, 1-celled and 1-ovuled.
Leaves with sheathing stipules (ocreae).
Order POLYGONALES. 443
Leaves estipulate, or stipules present if they are not
Trees or shrubs.
Anthers opening by slits: ovary not seated in a
hypanthium. Ulmaceae in Order URTICALES. 440
Anthers opening by hinged valves: ovary seated
in an accrescent hypanthium.
Lauraceae in Order THYMELEALES. 926
Herbs or vines.
Leaves with stipules.
Stipules herbaceous: inflorescence spicate or
racemose: leaf-blades palmately veined.
Cannabinaceae in Order URTICALES. 436
Stipules scarious or hyaline: inflorescence
cymose: leaf-blades pinnately veined.
Families in Order CHENOPODIALES. 461
Leaves without stipules.
Stigmas entire. Order CHENOPODIALES. 461
Euphorbiaceae in Order EUPHORBIALES. 775
Ovary several-celled, or with several placentae, several-
Stamens hypogynous, inserted under the gynoecium in
..i .... per-decfflbwers, not on a disk in the pistillate
Fruit baccate or nut-like, or a circum-
scissile capsule, the carpels terminal on
Families in Order CHENOPODIALES. 461
Fruit of several carpels, lateral on the
receptacle, each carpel circumscissile.
Penthoraceae in Order ROSALES. 589
Stamens not tetradynamous, 4-8: ovary
1-celled. Order CHENOPODIALES. 461
Stamens tetradynamous: ovary 2-celled.
Brassicaceae in Order PAPAVERALES. 551
Flowers monoecious or dioecious.
Ovules with the raphe towards the axis of
Euphorbiaceae in Order EUPHORBIALES. 775
Ovules with the raphe away from the axis
of the gynoecium.
Buxaceae in Order SAPINDALES. 806
Trees or shrubs.
Gynoecium 5-carpellary, the carpels nearly dis-
tinct. Buettneriaceae in Order MALVALES. 861
Gynoecium 2-4-carpellary, the carpels united.
Ovary 4-celled: fleshy maritime shrubs.
Batidaceae in Order CHENOPODIALES. 486
Ovary 2-celled: plants not fleshy.
Oleaceae in Order OLEALES. 1037
Stamens perigynous or epigynous, inserted on the mar-
gin of a hypanthium or a disk.
Fruit a samara. Families in Order SAPINDALES. 805
Fruit not a samara.
Fruit drupe-like or berry-like: shrubs or trees.
Order RHAMNALES. 830
Fruit a capsule: herbs. Order ARISTOLOCHIALES. 1279
Flowers not in involucrate heads.
Fruit 3-winged, splitting into 3 nutlets.
Gouania in Order RHAMNALES. 834
Fruit neither 3-winged nor splitting into carpels.
Fruit a berry or a drupe, or nut-like.
xviii KEY TO THE ORDERS
Calyx deciduous as a lid: stamens numerous.
Calyptranthes in Order MYRTALES. 937
Calyx of valvate or imbricated sepals: sta-
Stamens as many as the perianth-members
and alternate with them, or fewer.
Herbs, with succulent stems and leaves,
or woody below: flowers perfect.
Order CHENOPODIALES. 490
Trees or shrubs: flowers dioecious.
Nyssaceae in Order AMMIALES. 956
Stamens as many as the perianth-members
and opposite them, or twice as many.
Ovules mostly on basal placentae,
sometimes pendulous: cotyledons
not convolute: tree- or root-
parasites. Order SANTALALES. 1247
Ovules not on basal placentae:
cotyledons convolute: not para-
Families in Order MYRTALES. 925
Styles wanting: stigmas sessile.
Gunneraceae in Order IMYRTALES. 953
Fruit a capsule.
Sepals as many as the ovary-cavities or one
half as many.
Calyx regular and the sepals half as
many as the cavities in the ovary, or
irregular. Order ARISTOLOCHIALES. 1279
Calyx regular and the sepals as many as
the cavities in the ovary.
Order MYRTALES. 925
Sepals (4-5) at least twice as many as the
Saxifragaceae in Order ROSALES. 590
Flowers, at least the staminate, in involucrate heads.
Ambrosiaceae in Order CARDUALES. 1297
Petals distinct, at least at the base.
'Carpels solitary, or several and distinct, or united only at the base.
Stamens at the base of the receptacle, i.e., hypogynous.
Flowers in monoecious heads. Platanaceae in Order ROSALEs. 604
Flowers not in monoecious heads.
Plants with relatively firm stems and leaves, not succulent.
Order RANALES. 508
Plants with succulent stems and leaves.
Sedaceae in Order ROSALES. 585
Stamens on the margin of a hypanthium (the hypanthium very small
in some Saxifragaceae).
Plants without secreting glands in the bark. Order ROSALES. 583
Plants with secreting glands in the bark.
Surianaceae in Order GERANIALES. 761
Carpels several and united.
Stamens inserted at the base of the ovary or receptacle.
Calyx deciduous. Order PAPAVERALES. 546
Stigmas pinnatifid: insectivorous plants.
Dionaeaceae in Order SARRACENIALES. 580
Stigmas not pinnatifid: plants not insectivorous
(except in Sarraceniales).
Styles or stigmas distinct or united, but not dis-
Leaves glandular or pellucid-punctate.
Rutaceae in Order GERANIALES. 756
Canellaceae in Order HYPERICALES. 864
Leaves not glandular.
Placentae parietal: gynoecium with a 1-
Anther-sacs opening lengthwise.
Capparidaceae in Order PAPAVERALES. 575
KEY TO THE ORDERS
Anther-sacs opening at the top.
Bixaceae in Order HYPERICALES. 864
Placentae axile or central: gynoecium
with a 2-several-celled ovary, (or with
Theaceae in Order HYPERICALES. 875
Styles or stigmas united into a disk.
Herbs: bog or aquatic plants.
Petals and sepals numerous: leaves with
flat blades: aquatic plants.
Nymphaeaceae in Order RANALES. 540
Petals and sepals few : leaves with pitcher-
like organs: bog plants.
Sarraceniaceae in Order SARRACENIALES. 580
Shrubs or trees: plants not aquatic.
Clusiaceae in Order HYPERICALES. 865
Stamens with distinct filaments.
Ovary 1-celled: placentae parietal.
Capparidaceae in Order PAPAVERALES. 575
Ovary 2-several-celled : placentae axile or central.
Families in Order MALVALES. 840
Stamens with united filaments. Order MALVALES. 840
Stamens few, not over twice as many as the petals.
Stamens as many as the petals and opposite them.
Anther-sacs opening by hinged valves.
Podophyllaceae in Order RANALES. 543
Anther-sacs opening by slits.
Euphorbiaceae in Order EUPHORBIALES. 775
Ovules, or seeds, several or many: embryo coiled.
Portulacaceae in Order CHENOPODIALES. 493
Ovules, or seeds, solitary; embryo straight.
Armeriaceae in Order PRIMULALES. 1020
Stamens as many as the petals and alternate with them, or
more, sometimes twice as many.
Stamens 6: petals 4: sepals 2 or 4.
Families in Order PAPAVERALES. 546
Stamens, petals and sepals of the same number, or sta-
mens more, usually twice as many as the sepals or
Ovules, or seeds, on basal or central placentae.
Herbs. Families in Order CHENOPODIALES. 461
Trees or shrubs.
Stamens with free and distinct filaments.
Tamaricaceae in Order HYPERICALES. 866
Stamens with partially united filaments, and
usually adnate to the corolla.
Styracaceae in Order EBENALES. 1036
Ovules, or seeds, on parietal placentae.
Anther with an inconspicuous connective.
Stigmas not brush-like.
Droseraceae in Order SARRACENIALES. 578
Turneraceae in Order HYPERICALES. 877
Anther with the conspicuous connective pro-
duced beyond the sacs.
Papayaceae in Order PASSIFLORALES. 894
Stamens with united filaments and no stami-
nodia. Families in Order MALVALES. 840
Stamens with distinct filaments.
Parnassiaceae in Order ROSALES. 589
Families in Order HYPERICALES. 864
Stamens adnate to the gynoecium.
Asclepiadaceae in Order ASCLEPIADALES. 1064
Stamens not adnate to the gynoecium.
Stamens with wholly or partly united filaments.
Anthers opening lengthwise.
Families in Order GERANIALES. 743
Anthers opening by pores.
Polygalaceae in Order POLYGALALES. 765
Stamens with distinct filaments.
KEY TO THE ORDERS
Anthers opening by pores.
Families in Order ERICALES. 986
Anthers opening by slits.
Stigmas or styles distinct and cleft, or
foliaceous, or united by pairs.
Order EUPHORBIALES. 774
Stigmas or styles all distinct or all united,
neither cleft nor foliaceous.
Stamens 2. Oleaceae in Order OLEALES. 1037
Stamens more than 2.
Leaves with compound blades.
Families in Order GERANIALES. 743
Leaves with simple blades.
Ovule solitary in each carpel.
Styles distinct: ovule pendu-
lous. Families in Order
Styles united: ovule erect or
Order SAPINDALES. 753
Ovules 2 or more in each carpel.
Flowers irregular: stamens
united at the top or
Order GERANIALES. 753
Violaceae in Order
Flowers regular: stamens
neither united nor con-
verging at the top.
Carpels not circumscis-
sile at maturity.
Placentae axile or
tate : fila-
Carpels circumscissile at
Order ROSALES. 589
Stamens inserted on the margin of a disk or hypanthium (perigyn-
ous or hypogynous).
Stamens fewer than the sepals or the petals.
Hippocrateaceae in Order SAPINDALES. 820
Stamens as many as the sepals or the petals, or more.
Stamens as many as the petals and opposite them.
Styles and upper part of the ovaries distinct: ovules
and seeds many. Saxifragaceae in Order ROSALEs. 590
Ovules and seeds numerous.
Moringaceae in Order PAPAVERALES. 578
Ovules and seeds solitary or 2.
Order RHIAMNALES. 830
KEY TO THE ORDERS xxi \
Stamens as.,many as the petals and alternate with them,
or more or many.
Styles distinct and separate.
Upper part of the ovaries distinct, at least at ma-
Saxifragaceae and Iteaceae in Order ROSALES. 590
Upper part of the ovaries united. Order SAPINDALES. 804
Hypanthium flat or obsolete: disk fleshy.
Plants without secreting glands in the bark.
Order SAPINDALES. 804
Plants with secreting glands in the bark.
Families in Order GERANIALES. 743
Hypanthium cup-shaped or campanulate: disk obso-
lete or inconspicuous. Order MYRTALES. 925
Styles and stigmas united into a disk: water-plants with en-
dogenous stems. Nymphaeaceae in Order RANALES. 540
Styles distinct, or united, but not forming a disk with radi-
ating stigmas: land-plants with exogenous stems.
Stamens distinct: stigmas simple: shrubs or trees.
Families in Order ROSALES. 583
Stamens with united filaments: styles branched: herbs.
Order BEGONIALES. 917
Shrubs or trees, not succulents, sometimes woody vines.
Hypanthium not produced beyond the ovary.
Hydrangeaceae in Order ROSALES. 596
Hypanthium produced beyond the ovary.
Families in Order MYRTALES. 925
Herbs, or shrub-like or tree-like succulents.
Order OPUNTIALES. 896
Stamens not more than twice as many as the petals.
Styles wanting: stigmas sessile.
Gunneraceae in Order MYRTALES. 953
Ovules several in each cavity of the ovary: fruit a cap-
sule or a fleshy many-seeded berry.
Fruit, if dehiscent, valvate.
Families in Order ROSALES. 508
Portulacaceae in Order CHENOPODIALES. 493
Ovules solitary in each cavity of the ovary: fruit a
drupe or 2-5 more or less united achenes.
Order AMMIALES. 955
Styles united, or single.
Plants without tendrils.
Ovary enclosed in or surpassed by the hypanthium
or adnate to it.
Anther-sacs opening by pores.
Vacciniaceae in Order ERICALES. 1006
Anther-sacs opening by slits.
Ovules solitary in each cavity of the ovary.
Order AMMIALES. 955
Ovules several in each cavity.
Ovary with parietal placentae.
Loasaceae in Order OPUNTIALES. 897
Ovary with central or basal placentae.
Families in Order MYRTALES. 925
Ovary exceeding the hypanthium, the top free.
Hydrangeaceae in Order ROSALES. 596
Plants with tendrils.
Herbs: fruit a pepo: leaf-blades palmately veined.
Cucurbitaceae in Order CAMPANULALES. 1283
Shrubby vines: fruit drupaceous, separating into
nutlets: leaf-blades pinnately veined.
Frangulaceae in Order RHAMNALES. 830
Petals more or less united.
tamens free from the corolla.
Gynoecium of a single carpel. Families in Order ROSALES. 508
Gynoecium of several united carpels.
Stamens diadelphous. Fumariaceae in Order PAPAVERALES. 549
KEY TO THE ORDERS
Anther-sacs opening by slits.
Oxalidaceae in Order GERANIALES. 745
Anther-sacs opening by pores.
Calyx and corolla very irregular.
Order POLYGALALES. 765
Calyx and corolla regular.
Families in Order ERICALES. 986
Styles wanting or very short: stigma sessile.
Aquifoliaceae in Order SAPINDALES. 813
Ovary several-celled. Families in Order ERICALES. 981
Ovary 1-celled. Armeriaceae in Order PRIMULALES. 1020
Stamens partially adnate to the corolla.
Stamens as many as the lobes of the corolla and opposite them,
or twice as many or more.
Placentae central or basal. Order PRIMULALES. 1020
.Fouquieriaceae in Order HYPERICALES. 864
Upper portion of the ovaries distinct.
Sedaceae in Order ROSALES. 585
S Upper portion of the ovaries united. Order EBENALES. 1030
Stamens as many as the lobes of the corolla and alternate with them,
Corolla not scarious, veiny: fruit various, but not a pyxis.
Gynoecium of 3-6 carpels.
Shrubs or trees: ovules and seeds few.
Aquifoliaceae in Order SAPINDALES. 813
Herbs, or creeping or tufted shrubby plants: ovules and
seeds numerous or few in some members of the
Stamens adnate up to the sinuses of the corolla: creep-
ing evergreen under-shrubs.
Diapensiaceae in' Order ERICALES. 1018
Stamens adnate to the lower part of the corolla-tube:
herbs, undershrubs, or vines.
Families in Order POLEMONIALES. 1078
Gynoecium of 2 carpels.
Carpels distinct, except sometimes at the apex.
Style terminal. Order ASCLEPIADALES. 1057
Style basal. Dichondraceae in Order POLEMONIALES. 1079
Ovary 1-celled, with central placentae.
Order GENTIANALES. 1044
Ovary 2-celled, or falsely 4-celled, or if 1-celled with
Stamens 2 and opposite each other, or 3.
Order OLEALES. 1037
Stamens usually 4 or 5, if 2 by reduction not oppo-
site each other.
Leaves with stipules or stipular lines at their
bases. Spigeliaceae in Order GENTIANALES. 1044
Leaves with no traces of stipules.
Families in Order POLEMONIALES. 1078
Corolla scarious, veinless: fruit a pyxis. Order PLANTAGINALES. 1244
Stamens with the filaments free from the corolla.
Stamens 10: anther-sacs opening by terminal pores or chinks.
Vacciniaceae in Order ERICALES. 1006
Stamens 5 or fewer: anther-sacs opening by longitudinal slits.
Order CAMPANULALES. 1283
Stamens adnate to the corolla.
Ovary with 2-many fertile cavities and 2-many ovules: calyx un-
modified, at least not a pappus.
Cucurbitaceae in Order CAMPANULALES. 1283
Plants not tendril-bearing.
Ovules mostly on basal placentae: plants parasitic.
Order SANTALALES. 1247
Ovules variously borne, but not on a basal placenta: plants
not parasitic. Order RUBIALES. 1251
Ovary with one fertile cavity.
Ovules numerous on a basal placenta.
Primulaceae in Order PRIMULALES. 1020
Ovule solitary, the placentae not basal.
Flowers not in heads, often in head-like spikes or racemes.
Order VALERIANALES. 1276
Flowers in involucrate heads. Order CARDUALES. 1297
SUBKINGDOM SPERMATOPHYTA SEED-PLANTS
Plants producing flowers and seeds. A seed contains an em-
bryo consisting of a short stem radiclee, caulicle, or hypocotyl),
one, two, or several rudimentary leaves cotyledonss), and a term-
inal bud (plumule).
CLASS 1. GYMNOSPERMAE CONE-PLANTS
Carpel or pistil represented by a scale on the face of which the
ovules are borne, and on which the naked seeds mature.
ORDER CYCADALES-CYCADAL ORDER
Palm-like or fern-like plants. Leaves in a crown: blades pinnate.
Flowers in cones of approximate scales or on less modified leaves. Stam-
inate cone with scales bearing several pollen-sacs. Ovulate cone with two
or more ovules on each scale. Seed drupe-like or nut-like.
FAMILY 1. CYCADACEAE SAGO-PALM FAMILY
Dioecious plants with subterranean or aerial stems. Leaves clustered:
leaflets with 1 or several ribs or veins. Staminate cone deciduous. Ovu-
late leaf or cone persistent. Seeds exposed on the margins of the ovu-
late leaf or enclosed in a cone.-The most primitive living seed-plants,
even showing some characters of the ferns in their structure. There are
about 9 genera and nearly 100 species in tropical and subtropical regions.
1. ZAMIA L. Fern-like plants with erect, simple, or sometimes branched,
subterranean, stout, fleshy, farinaceous, stems. Leaves erect or spreading: leaf-
lets jointed to the rachis, with parallel veins. Cones stalked, the staminate one
more slender than the ovulate one: scales peltate, spiral. Mature ovulate cone
erect.-Represented by four species in Florida, but more abundantly in the
West Indies and continental tropical America, where other genera occur as
well.-COONTIES. CONTIS. COMPTIES. COMFORTROOTS. FLORIDA-ARROWROOTS.
WILD-SAGOS.-The zamias were known to the early Seminoles as Conti Hateka
which means white-root or white bread-plant.
Blades of the leaflets of a narrow type, 8-20-veined, entire or obscurely toothed at
Leaflets close together on the rachis, mostly less than 11 cm.
long. 1. Z. integrifolia.
Leaflets rather distant on the rachis, mostly over 12 cm.
Blades of the leaflets narrowly linear-attenuate, 10-14-
veined, 6 mm. wide or less. 2. Z. angustifolia.
Blades of the leaflets broadly linear, 14-20-veined, 10
mm. wide or more. 3. Z. silvicola.
Blades of the leaflets of a broad type, 20-30-veined, evidently
callous-toothed at the apex. 4. Z. umbrosa.
1. Z. integrifolia Ait. Leaves 4-9 dm. long; leaflets 8-11 cm. long, the blades
linear, 3-7 mm. wide, 8-16-veined, often revolute and very stiff: staminate
cone narrowly cylindric, 8-13 cm. long:
mature ovulate cone cylindric-ellipsoid, 12-
16.5 cm. long: nut-like part of seed ellip-
sold, 17-19 mm. long, nearly terete.
[Z. floridana DC.]-Dry sandy pinelands or
rarely coastal dunes, pen. and N Fla., and
occasionally lower Keys.-The starchy un-
derground stem of this cycad was the main
native source of flour for the Fla. aborigines
and for the Seminoles. The phenomenal
growth on the Everglade Keys now fur- '
nishes "Florida arrowroot" to the white-
man. The stems are frequently branched.
2. Z. angustifolia Jacq. Leaves 1-2'm.
long: leaflets 12-20 cm. long, the blades
narrowly linear-attenuate, 3-6 mm. wide, 10-14-veined, flat or nearly so,
minutely toothed at the apex: inflorescence not seen in Fla. (Bahamian speci-
mens are described as having oblong-cylindric staminate cones 5-7 cm. long and
mature ovulate cones 8-9 cm. long.)-Humus, wet hammock islands, between
Royal Palm Hammock and Cape Sable, Fla.-(W. I.)-The stems are large but
3. Z. silvicola Small. Leaves 1 m. long or less; leaflets 12-17 cm. long, the
blades linear, often broadly so, 1-1.5 cm. wide, 14-20-veined, flat, obscurely
toothed at the apex: staminate cone cylindric or slightly tapering upward, 8-16
cm. long: mature ovulate cone ellipsoid-cylindric, mostly 9-14 cm. long: nut-
like part of seed broadly obovoid, 18-20 mm. long, decidedly flattened, minutely
pointed at both ends.-Humus, rich sandy soil, aboriginal village sites, and
shell mounds, pen. Fla.-Our most robust zamia, often abundant on the upper
western coast, and locally in hammocks to the S. Plants on the shell mounds
often have branching stems.
4. Z. umbrosa Small. Leaves mostly less than 0.5 m. long; leaflets 7-11 cm.
long, the blades linear-oblanceolate, linear-elliptic, or broadly linear. 8-16 mm.
wide, 20-30-veined. flat, callous-toothed at the apex, firm: staminate cone nar-
rowly cylindric, 7-11 cm. long: mature ovulate cone cylindric, 6.5-11 cm. long
or rarely longer: nut-like part of seed obovoid, 15-17 mm. long, evidently
3-sided. [Z. pumila (Fl. SE. U. S.) ]-Hammocks, sand-dunes, and shell mounds,
NE Fla.-Primarily a hammock plant and especially abundant on the kitchen-
middens and aboriginal village sites of the upper eastern coast. The stems are
ORDER PINALES PINAL ORDER
Shrubs or trees. Leaves scale-like, narrow, or needle-like, and often
borne in bundles. Flowers mainly monoecious, the cones of spirally imbri-
cate bracts, or in Taxaceae the ovulate flowers often solitary. Seed borne
in a cone of dry or fleshy scales, or partly or wholly naked.-A group de-
veloped later and more highly organized than the CYCADALES.
Ovulate flowers several, with carpellary scales, these sometimes bracted: cone with
either dry or fleshy scales.
Carpellary scales with bracts, not peltate: ovules inverted: buds scaly: wing
accompanying the seed a portion of the carpellary
scale. Fam. 1. PINACEAE.
Carpellary scales without bracts, mostly peltate, or
fleshy: ovules erect: buds naked: wing of the seed,
when present, a portion of the testa. Fam. 2. JUNIPERACEAE.
Ovulate flowers solitary or 2, without carpellary scales:
cone drupaceous or baccate. Fam. 3. TAXACEAE.
FAMILY 1. PINACEAE PINE FAMILY
Mostly evergreen resin-yielding shrubs or trees, typically conic, with
flaky or brittle bark, the buds scaly. Leaves narrow and solitary or
needle-like and usually several together, each group with a sheath at the
base. Ovulate ament with bracted scales. Ovules inverted. Cone of dry
scales. Seeds usually 2 on each scale, often samara-like.-A family of the
first economic importance: its members furnish lumber, resinous products,
tanning materials, volatile oils. The species fall into a dozen genera of
wide geographic distribution.
Leaves several together, the bundle surrounded by a sheath at the base: cones matur-
ing the second year. Tribe I. PINEAE.
Leaves solitary, without a sheath: cones maturing the first
year. Tribe II. ABIETINEAE.
Cone-scales with dorsal, spine-armed appendages: leaves in
2's or 3's. 1. PINUs.
Cone-scales with terminal unarmed appendages: leaves in 5's. 2. STaOBUS.
Cone drooping: bracts shorter than the cone-scales.
Leaves 4-sided or nearly terete, spreading: anther-sacs opening
lengthwise. 3. PICEA.
Leaves flat, apparently 2-ranked: anther-sacs opening trans-
versely. 4. TSUGA.
Cone erect; bracts longer than the cone-scales. 5. ABIES.
1. PINUS [Tourn.] L. Trees or rarely shrubs. Leaves needle-like, mostly
in 2's or 3 's and each with 2 fibro-vascular bundles. Staminate agents elon-
gate, at the ends of branches of the preceding year. Ovulate ament globular or
slightly elongate. Cone spreading: scales at length woody and spreading, each
with a dorsal, usually spine-armed appendage. Seed samara-like.-About 75
species, mostly in the north temperate zone.-Spr.-PINES.--Most of our pines,
especially the long-leaved ones, are important timber trees.
Branchlets terminated by plumes of relatively long, curved or recurved leaves.: resin-
ducts of the leaf contiguous to the fibro-vascular bundle. I. AUSTRALES.
Branchlets terminated by brushes of relatively short, stiff,
straight leaves: resin-ducts of the leaf remote from the
fibro-vascular bundle. II. RIGIDAE.
Cone elongate, of a conic type and over twice as long as thick
when closed, slightly umbonate, the scale-appendages flat
or slightly elevated, with recurved or hooked prickles.
Cone-scales thin-edged, the appendages flattish, the prickles
hooked. 1. P. australis.
Cone-scales thick-edged, the appendages turgid, the prickles
slightly recurved. 2. P. caribaea.
Cone short, of an ovoid type and less than twice as long
as thick when closed, prominently umbonate, the scale-
appendages elevated, often pyramidal, with nearly straight
or decurved prickles. 3. P. palustris.
Scales of the ovulate ament stout, each with a short tip which
scarcely equals the body in length.
Cone over 8 cm. long.
Cone broadly conic when closed and prominently um-
bonate; scales thick-edged, the appendages projecting
little, if at all, beyond the short spine. 4. P. Taeda.
Cone narrowly conic when closed, and slightly um-
bonate; scales thin-edged, the appendage projecting
far beyond the long spine.
Cone less than 8 cm. long.
Cone ovoid or globular-ovoid when closed: leaves 15-25
cm. long, about 2 mm. wide.
Cone narrowly conic when closed: leaves 4-12 cm. long,
about 1 mm. wide.
Cone-scales readily opening, each with a slender or
minute spine towards the front of the appen-
dage, the spine sometimes deciduous or ob-
Cone-scales with minute, deciduous or obsolete
spines: scales of the staminate aments erose-
toothed at the apex: bark of the trunk rela-
tively close and smooth.
Cone-scales with slender persistent spines: scales
of the staminate aments entire: bark of the
trunk broken into angular plates.
Cone-scales tardily opening or permanently closed,
each with a stout spine at the middle or towards
the back of the appendage.
Scales of the ovulate ament slender, each with a subulate tip
several times the length of the body.
Cone conic when closed, ovoid when open: twigs glaucous.
Cone ovoid when closed, globose-ovoid or depressed when
open: twigs yellow.
Scales of the pistillate ament recurved: appendages of
the cone-scales relatively thin; spines slender, more
or less recurved.
Scales of the pistillate ament ascending: appendages
of the cone-scales very thick; spines stout, more or
5. P. heterophylla.
6. P. serotina.
7. P. glabra.
8. P. echinata.
9. P. clausa.
10. P. virginiana.
11. P. rigida.
12. P. pungens.
1. P. australis Michx. f. Tree becoming 40 m. tall, irregularly branched above,
the bark in large plates: leaves typically in 3 's, 20-40 cm. long, bright-green,
borne in terminal plumes, on twigs about
1 cm. in diameter: staminate ament 5.5-8
cm. long: cone 16-25 cm. long, ascending
when young, narrowly conic when closed,
broadly conic when open, each scale-appen-
dage with a recurved spine: seed 12-13 mm.
long, the wing 4.5-5 cm. long. [P. palustris
(Fl. SE. U. S.)]-(LONG-LEAF PINE. LONG-
STRAW PINE. YELLOW-PINE. GEORGIA-PINE.
SOUTHERN-PINE. PITCH-PINE.)---Sandy soil,
usually dry and acid, Coastal Plain and
rarely adj. provinces, Fla. to Tex., N Ala.,
and S Va.-The giant of our pines, as well
as the one with the longest leaves and the
largest cones. A timber. tree of the first im-
portance, and the principal source of rosin and turpentine in the U. S.
2. P. caribaea Morelet. Tree usually smaller than P. australis: leaves in 2 's
or 3 's, 18-30 cm. long (rarely shorter), bright-green, on twigs about 5 mm. in
diameter: staminate ament 2.5-4 cm. long: half mature ovulate ament ascending:
cone 8-15 cm. long, recurving when young, cylindric-conic when closed, cylindric
or ovoid-cylindric when open: each scale-appendage turgid: seed 4-7 mm. long,
the wing 2-2.5 cm. long, or smaller.-(SLASH-PINE. CARIBBEAN-PINE. ROOK-
PINE.)-Dry sandy or rocky soil, often calcareous, pen. Fla. and the lower Keys,
extending near the coast to Miss. and Ga.-(W. I.)-The only pine growing
naturally on the Florida Keys.
3. P. palustris Mill. Tree becoming 30 m. tall: leaves in 2 's or 3 's, deep-green:
staminate ament 3.5-5 cm. long: half mature ovulate ament recurved: cone 8-12
cm. long, narrowly ovoid when closed, broadly ovoid when open, each scale-
appendage very prominent: seed 6-8 mm. long, the wing 2-3 cm. long. [P.
Elliottii Engelm.]-(SLASH-PINE. SWAMP-PINE.)-Shallow ponds, swamps, and
low grounds, often acid, Coastal Plain, C Fla. to E La. and S. C.-Inhabiting
the lower or wet situations within the range of P. australis, and thriving under
the influence of either salt or fresh water. The cones are about as long as those
of the next preceding species, but broader.
4. P. Taeda L. Tree becoming 45 m. tall, the dark bark deeply furrowed, very
rough, exfoliating in coarse plates: leaves in 3's, glaucous, 15-28 cm. long:
cone 10-13 cm. long, broadly conic when closed, ovoid or conic-cylindric when
open, the scale-appendages thick, projecting little, if at all, beyond the small
spine: seed 6-7 mm. long, the wing about 2 cm. long.-(LOBLOLLY-PINE. SHORT-
LEAF PINE. OLDFIELD-PINE.) -Sandy or clay soil, frequently acid, Coastal Plain
and rarely adj. provinces, Fla. to Tex., Ark., Tenn., and S N. J.-After the
manner of a weed completely foresting abandoned cultivated lands.
5. P. heterophylla (Ell.) Sudw. Tree becoming 35 m. tall, the pale bark
shallowly furrowed: leaves in 2 's or 3 's, glaucous, 12-25 cm. long, often stouter
than in P. Taeda: cone 9-14 cm. long, conic when closed, ellipsoid or ovoid-
cylindric when open, the scale-appendages thin, projecting beyond the slender
spine: seed 5-7 mm. long, the wing 2-2.5 cm. long.-(POND-PINE. SLASH-PINE.)
-Sandy swamps, near the coast, Ga. and S. C.-It produces the palest bark and
the softest wood of our pines and has the most restricted range.
6. P. serotina Michx. Tree becoming 25 m. tall, with many short irregular
branches near the base, the bark flaky: leaves in 3 's, glaucous, 15-28 cm. long,
crowded; sheath about 12 mm. long: staminate ament 1.5-2 cm. long: cone
4-6 cm. long, ovoid or globular-ovoid when closed, very broad when open, each
scale with a thick appendage and a minute spine: seed 3-4 mm. long, the wing
2 cm. long.-(BLACK-PINE. POND-PINE. MARSH-PINE.)-Sandy swamps and
shallow ponds, frequently acid, Coastal Plain, Fla. and Ala. to S N. J.-The
cones are much shorter and thicker than in its relatives.
7. P. glabra Walt. Tree becoming 40 m. tall, with a relatively smooth grayish
bark: leaves in 2's, glaucous, 4-8 cm. long, very slender; sheath 5-8 mm. long:
staminate ament about 1 cm. long: cone 3.5-5 cm. long, conic when closed, ovoid
when open, each appendage with a minute or almost obsolete spine: seed about
4 mm. long, the wing usually 1.5 cm. long.-(SPRUCE-PINE. CEDAR-PINE.
WHITE-PINE. WALTER'S-PINE.) -Hammocks, bluffs and bottoms, Coastal Plain,
N Fla. to E La. and S. C.-Readily distinguished by the smooth bark, the
very slender leaves, and the small nearly unarmed cones.
8. P. echinata Mill. Tree up to 40 m. tall, the bark splitting into angular
plates: leaves in 2's or occasionally in 3's, deep-green, 8-12 cm. long, slen-
der; sheath 10-15 mm. long: cone 3.5-6.5 cm. long, conic when closed, ovoid
when open, each appendage with a slender spine: seed 4-5 mm. long, the wing
1.5-2 cm. long. [P. mitis Michx.]-(SHORT-LEAF PINE. YELLOW-PINE. FOX-
TAIL-PINE.)-Dry sterile and frequently acid soils, various provinces, N Fla. to
Tex., SE Kans., Ind., and S N. Y.-This wide-ranging species may be distin-
guished from its associates by its slender leaves.
9. P. clausa (Engelm.) Vasey. Tree becoming 24 m. tall, the bark relatively
smooth: leaves in 2's, deep-green, 4-8 cm. long, very slender; sheath 5-7 mm.
long: cone 4.5-6 cm. long, conic when closed, ovoid when open, each scale-
appendage with a stout spine near the middle: seed 4 mm. long, the wing
about 1.5 cm. long.-(SAND-PINE. SPRUCE-PINE.)-Acid sand-ridges and dunes
near the coast, and scrublands, Fla. and adj. Ala.-May be recognized by the
numerous slender leaves and the persistent cones which are often slow to open.
10. P. virginiana Mill. Tree becoming 36 m. tall, the bark rough and the
branches sinuous, the twigs glaucous: leaves in 2 's, deep-green, 4-7 cm. long,
rather stout; sheath 5-8 mm. long: cone 5-7 cm. long, narrowly conic when
closed, ovoid when open, each scale-appendage with a curved spine: seed 4-5
mm. long, the wing fully 1.5 cm. long. [P. inops Ait.]-(SCRUB-PINE. JERSEY-
PINE. POVERTY-PINE.)-Dry sterile soils, various provinces, C Ga. to E Miss.,
S Ind. and S N. Y.-Characterized by its short stubby leaves and medium-sized
11. P. rigida Mill. Tree becoming 25 m. tall, with stiff branches, the bark
very rough, the twigs yellow: leaves in 3 's, bright-green, 6-12 cm. long, rather
stout; sheath 10-15 mm. long: cone 4-7 cm. long, ovoid when closed, globose-
ovoid or depressed when open, the scale-appendages relatively thin, each with a
recurved spine: seed 4-4.5 mm. long, the wing about 1.5 cm. long.-(PITCH-
PINE.)-Sterile and usually acid soils, various provinces, N Ga. to Ont. and N. B.
12. P. pungens Lamb. Tree becoming 18 m. tall, the bark rather smooth, but
flaky: leaves in 2's, bright-green, 5-10 cm. long, stout, rigid: cone 8-12 cm.
long, very persistent, ovoid when closed, globose-ovoid or depressed when open,
the scale-appendages very thick, each with a stout incurved spine: seed 6-7
mm. long, the wing fully 2 cm. long.-(TABLE-*MOUNTAIN PINE. TABLE-ROCK
PINE. MOUNTAIN-PINE.)-Rocky acid soil and cliffs, Piedmont to Appalachian
provinces, N Ga. to Pa. and N. J.-Has stout leaves and very stout cones with
prominently armed scales. Cones often persist on the branches for many years.
2. STROBUS Opiz. Trees. Leaves needle-like, 5 together, mostly with
1 fibro-vascular bundle each. Staminate aments with involucral bracts at the
base. Ovulate ament narrow, stalked. Cone drooping: scales leathery, with
neither dorsal appendage nor spine.-A genus represented in eastern North
America by the following and in the Pacific States by several other species.
1. S. Strobus (L.) Small. Tree becoming 50
m. tall, with a relatively smooth bark and ap-
proximately whorled branches: leaves 5 to-
gether, 5-10 cm. long, glaucous, very slender;
sheath deciduous or fugacious: cone narrow,-
slightly tapering when open, 10-20 cm. long,
often curved; scales loosely spreading: seed
6-7 mm. long, the wing about 2.5 cm. long.
[Pinus Strobus L.]-(WHITE-PINE).-Sandy
or rocky soil, various provinces, N Ga. to
Man. and Newf.-Spr.-The most widely
distributed species of the white pines. Its
five-fascicled slender leaves and long unarmed
cones readily distinguish it from other pines.
Once the most important of American timber
trees, but greatly depleted by reckless lumbering.
3. PICEA Link. Trees. Leaves solitary, ascending or erect, narrow,
angled or terete, leaving sterigmata when falling. Pollen-sacs opening length-
wise. Ovulate ament with inconspicuous bracts. Cone drooping.-Spr.-A
genus of 14 species of the more northern latitudes, represented in our area only
in the higher mountains.-SPRUCES.-Some species are timber trees, and are,
also, an important source of paper pulp.
Twigs stout, copiously pubescent: leaves over 1 mm. broad, blunt or
mucronate. 1. P. rubens.
Twigs slender, glabrate or merely pubescent between the decurrent
sterigmata: leaves barely 1 mm. broad, acute. 2. P. australis.
1. P. rubens Sargent. Tree often becoming 30 m. tall, the bark rough:
twigs stout, stiff, pubescent as are usually the sterigmata: leaves curved, 8-12
mm. long, deep-green: cone ellipsoid or ovoid,
2.5-4 cm. long. [P. mariana (Fl. SE. U.
S.) ]-(RED-SPRUCE. HE-BALSAM. TAMA-
RACK. YEW-PINE.) -Moist or rocky and a
usually acid soil, Blue Ridge and more north-
ern provinces, N. C. to Sask. and Newf.-
Often crowns mountain tops with a pure
growth. The black spruce-P. mariana
(Mill.) Britton-recorded as growing in the
N. C. Mts., has glaucous leaves and small
2. P. australis Small. Tree becoming 40 m. I__
tall, the bark relatively smooth: twigs slen-
der, glabrous or merely pubescent in lines
between the decurrent glabrous sterigmata: leaves slender, 8-14 mm. long,
straight or nearly so, bright-green: cone ellipsoid, oval or ovoid, mostly less
than 2.5 cm. long. [P. alba (Chapm. Fl.)]1-(SOUTHERN-SPRUCE. HE-BAL-
SAM.)-Dry acid slopes, summits, and cliffs, Blue Ridge, N. C. and Va.-Less
common than the preceding. Sometimes in forests unmingled with other trees.
4. TSUGA Carr. Trees. Leaves distichously spreading: blades linear,
glaucous beneath, not jointed to sterigmata. Pollen-sacs opening transversely.
Ovulate ament with inconspicuous bracts. Cone drooping. There are 7 species
native of North America and Asia.-HEMLOCKS.-Spr.-Some species are tim-
Twigs tomentose with long hairs: cones narrowly ovoid when closed, 1.8-2.3 cm.
long: scales nearly erect. 1. T. canadensis.
Twigs tomentose with short hairs, or glabrate: cones cylindric-
ellipsoid when closed, 3 cm. long: scales spreading at right
angles. 2. T. caroliniana.
1. T. canadensis (L.) Carr. Tree becoming 30 m. tall, with a scaly-exfoliating
bark: leaves loosely spreading, 6-14 mm. long, obtuse at the apex: staminate
ament 2 mm. in diameter: cone ellipsoid
when open, 18-23 mm. long; scales erect,
suborbicular or subcuneate: seed-wing mainly
less than 1 cm. long.-(CANADA-HEMLOCK.
NORTHERN-HEMLOCK. SPRUCE-PINE.) -Rocky
banks, woods, and ravines, various prov-
inces, Ga. and Ala. to Minn. and N. S.-Like
Picea rubens, this tree is fond of moist V
places and on slopes often forms extensive
forests. It is a graceful tree, with pliable
branches, soft foliage, and smooth cones.
2. T. caroliniana Engelm. Tree becoming \
25 m. tall, the bark relatively smooth:
leaves rigidly spreading, mostly notched
at the apex: staminate ament about 3 mm.
in diameter: cone ovoid when open, 25-30 mm. long; scales spreading or
nearly so: seed-wing ellipsoid, over 1 cm. long.-(CRAG-HEMLOCK. CAROLINA-
HEMLOCK.)-Ravines and rocky slopes, frequently acid, Blue Ridge, Ga. to
S Va.-A striking tree, but not graceful. The rigid branches are bristly with
the spreading leaves and even the cones are bristly on account of the widely
5. ABIES [Tourn.] Hill. Trees. Leaves distichously spreading on twigs
and branchlets: blades linear, not jointed to sterigmata. Pollen-sacs opening
transversely or nearly so. Ovulate ament with conspicuous bracts. Cone erect,
cylindric.-A genus characteristic of high latitudes and mountains, with only
2 species in the eastern United States, 8 species in western North America and
about a dozen in the Old World.--FRs.---
Some of the western species are valuable
timber trees. Canada balsam is an exuda-
tion in the blisters on the trunk of A.
1. A. Fraseri (Pursh) Lindl. Tree becom-
ing 25 mm. tall, the bark with balsam-yield-
ing blisters: leaves 1-2 cm. long; blades /
shining above, glaucous beneath: staminate
ament 5-8 mm. long: cone 4-5 cm. long;
scales flabellate: bracts exserted, apiculate:
seed 4-5 mm. long, the wing about as wide
as long.-(SILVER-FIR. BALSAM-FIR. SHE-
BALSAM. LASH-HORN. BLISTER-PINE.)-Acid
swamps, slopes, and summits, Blue Ridge to Appalachian Plateau, N. C. and
Tenn. to W. Va.-Spr.-A related northern species, A. balsamea, with included
cone-bracts, may occur in NW N. C.
FAMILY 2. JUNIPERACEAE JUNIPER FAMILY
Mostly evergreen often slightly resiniferous shrubs or trees, with
fibrous, shreddy bark, the buds naked. Leaves mainly appressed or some-
times subulate and spreading. Ovulate ament with bractless scales. Ovules
erect. Cone of dry, often thick, peltate scales, or baccate or drupaceous.
Seed wingless, or winged, the wing a portion of the testa.-About 12 gen-
era, widely distributed. The woods and the products are of great eco-
Plants monoecious: cones dry, merely imbricated.
Leaves long and narrow, not scale-like, spreading: scales of the ovulate cones
spirally placed, imbricate. Tribe I. TAXODIEAE.
Leaves scale-like, typically appressed and imbricate
(sometimes spreading on twigs) : scales of the ovu-
late cones decussately opposite or ternate. Tribe II. CUPRESSEAE.
Plants mostly dioecious: cone berry-like or drupe-like:
scales fleshy, coalescent. Tribe III. JUNIPEREAE.
Trees producing erect "knees" from the root-system: leaves
deciduous. 1. TAXODIUM.
Cones elongate: scales not peltate, the tip apically thickened,
often apiculate or hooked below the apex.
Cones drooping; scales not hooked near the apex: seeds
wingless: branchlets in horizontally disposed fronds. 2. THUJA.
Cones erect; scales hooked below the apex: seeds winged :
branchlets in vertically disposed fronds. 3. BIOTA.
Cones nearly globular; scales peltate, the conspicuously thick-
ened tops ending in short tips. 4. CHAMAECYPARIS.
Leaves subulate and spreading on the mature branches:
aments axillary, the pistillate with smaller scales at the top. 5. JUNIPERUS.
Leaves scale-like and appressed on the mature branches:
aments terminal, the pistillate with larger scales at the top. 6. SABINA.
1. TAXODIUM L. C. Rich. Deciduous-leaved trees, the roots producing
erect conic "knees." Leaves often almost 2-ranked: blades narrow. Staminate
aments in panicled spikes or racemes. Ovulate aments with peltate scales.
Cone spreading, globular or obovoid, the scales woody, stalked. Seed wingless.
-Comprises three species of the southern Atlantic and Gulf seaboard.-Spr.-
The wood has exceptionally durable qualities.-CYPRESSES.-Inhabitants of low
Leaves 2-ranked, widely spreading: branchlets usually horizontal: bark thin, com-
paratively smooth. 1. T. distichum.
Leaves appressed to the erect branchlets: bark thick, strongly
furrowed. 2. T. ascendens.
1. T. distichum (L.) L. C. Rich. Tree becoming 50 m. tall, the base of trunk
conic, narrowly ridged, the bark thin, relatively smooth: leaves 1-1.5 cm.
long, often curved: cone globular, about
2.5 cm. in diameter: seed 8-10 mm. long.-
(BALD-CYPRESS. RIVER-CYPRESS.) -Swamps,
or rarely rocky slopes, often over calcareous
subsoil, Coastal Plain and rarely adj. prov-
inces, Fla. to Tex., Mo., Ind. and N. J.;
also rare along the Hudson River, N. Y.,
where perhaps introduced.-The character-
istic cypress of river swamps. Often a very
large tree with the trunk gradually taper-
ing near the base. It is usually copiously
2. T. ascendens Brongn. Tree typically
smaller than T. distichum, but with very
similar inflorescence and fruit, the knees
less abundant, the trunk with a conoidal broadly ridged base: leaves incurved;
blades 0.5-1 cm. long. [T. imbricarium (Nutt.) Harper.]-(POND-CYPRESS.)
Pineland ponds, creeks, and small rivers, usually over a clay subsoil, rarely in
dry barrens, Coastal Plain, Fla. to La. and Va.-The cypress of ponds and
marshy places. It is less branched than the preceding. The bark is rougher
than that of T. distichum, and as a consequence the trees are sometimes
copiously infested with air-plants.
2. THUJA L. Evergreen trees. Leaves scale-like, 4-ranked, often with a
gland on the back. Staminate aments solitary. Ovulate ament with imbricate
scales. Cone drooping, ellipsoid or ovoid, the scales leathery, lax. Seeds
winged on both sides.-About 15 species, native of North America and Asia.
Only two species in America, one in the
eastern part and one in the western.-- \
1. T. occidentalis L. Tree up to 18 m.
tall, the branchlets in horizontally dis-
posed fronds. Leaves appressed, those of
the branches 5-7 mm. long: staminate ament
globose: ovulate ament with erect scale-tips:
cone 9-13 mm. long; scales obtuse, each
apiculate below the apex.-(WHITE-CEDAR.
AMERICAN-ARBORVITAE.)--Swamps or rocky
banks, usually calcareous, Blue Ridge and
more northern provinces, N. C. and Tenn.
to Man. and N. B.-Spr.-One of the cool
climate plants surviving in our range only in the mountains. It is used in
horticulture. The wood has few uses in the industries.
3. BIOTA Endl. Evergreen trees. Branchlets placed in a vertical plane,
with both sides alike. Leaves scale-like, 4-ranked, with a gland on the back.
Staminate aments solitary. Ovulate aments with fleshy imbricate scales. Cone
erect, slightly elongate, the scales leathery,
each with a stout hook below the apex.
Seeds thick, wingless.- Only one species,
native of eastern Asia, and widely cult.-
1. B. orientalis (L.) Endl. Tree 9 m.
tall or less, the branches in vertically dis-
posed fronds: leaves appressed, those of the
branches 2-4 mm long: staminate ament
ellipsoid: ovulate ament with recurved scale- j
tips: cone erect, mostly 15-25 mm. long;
scales hooked below the apex. [Thuja orien-
talis L.]-(CHINESE-ARBORVITAE. ASIATIC-
ARBORVITAE.)-Sandy soil, coast of Fla. Nat. of Asia.-All year.-Not ex-
tensively naturalized, but persistent about abandoned gardens and occasionally
4. CHAMAECYPARIS Spach. Trees. Leaves scale-like and imbricate,
each with a gland on the back, or sometimes subulate on twigs. Staminate
agents terminal. Ovulate aments with peltate scales. Cone spreading, globu-
lar: scales woody, appendaged. Seeds
winged. About 7 species, two in western
North America and several in eastern Asia.
1. C. thyoides (L.) B. S. P. Strong-scented
tree becoming 27 m. tall: leaves 1-2 mm.
long, appressed, the lateral ones keeled,
the vertical merely convex: staminate
ament 2-3 mm. long: ovulate ament glau-
cous, the scales with hyaline appendages:
cone globular, 5-7 mm. in diameter:
seed narrowly winged. [C. sphaeroidea
Spach.] (WHITE-CEDAR.) -Acid swamps,
Coastal Plain and rarely adj. provinces, N Fla. to Miss. and Me.--Spr.-A
tree somewhat resembling the arborvitae in habit, but with quite different
cones. It varies much in its mode of branching. The natural growth is being
rapidly depleted by cutting the trees for telephone poles. The wood has many
uses in the industries.
5. JUNIPERUS [Tourn.] L. Shrubs or trees. Leaves in 3 's, subulate,
neither imbricate nor appressed, glandless. Staminate aments axillary. Ovu-
late ament with ovules alternate with the scales. Cone baccate. Seeds wingless.
-Spr.-Consists of ten or fifteen species, mostly in the more northern parts of
the northern hemisphere.-JUNIPERS.
A depressed shrub, with creeping branches: leaves abruptly bent at the base, deeply
channeled, rather abruptly pointed. 1. J. sibirica.
A tree; leaves straight or nearly so, shallowly channeled, gradu-
ally acuminate. 2. J. communis.
1. J. sibirica Burgsd. Depressed shrub, the radiating branches rarely rising
over 5 dm., often matted: leaves stout, mostly 5-8 mm. long, abruptly curved
at the base, erect or erect-ascending,
abruptly pointed: cone globular, 8-10 mm.
in diameter.-(MouNTAIN-JUNIPER.) Dry
gravelly soil, Blue Ridge and more northern
provinces, N. C. to Rocky Mts., Alas., and
Lab.-(Eurasia.)-Our two species of juni-
per may be distinguished by habit alone.
The present one is always depressed with
the branches on the ground and only ascend-
ing at the tips.
2. J. communis L. Erect tree becoming 8
m. tall: leaves slender, 10-20 mm. long,
spreading, gradually narrowed at the apex:
cone globular, 6-8 mm. in diameter.-Dry
sandy hills, Blue Ridge and more northern
provinces, Ga. to N. M. and Can.-(Eurasia.)-Rare in our range.
6. SABINA Haller. Shrubs or trees. Leaves scale-like, except sometimes
on twigs, appressed, often imbricate, each with a gland in the back. Staminate
aments terminal on branchlets. Ovulate ament with ovules opposite the scales.
Cone baccate. Seeds wingless.-Spr.-About 25 species, most abundant north-
ward, but ranging southward to the West Indies and Mexico.-CEDARS. SAVINS.
Staminate ament 3-4 mm. long: cone 5-6 mm. long. 1. S. virginiana.
Staminate ament 4-5 mm. long: cone 3-4 mm. long. 2. S. silicicola.
1. S. virginiana (L.) Antoine. Tree becoming 30 m. tall: scale-like leaves
opposite, 4-ranked, 1-4 mm. long, acute: staminate ament 3-4 mm. long: cone
sub-globose, 5-6 mm. long, glabrous: seed
3-4 mm. long, smooth. [Juniperus vir.
giniana L.]-(RED-CEDAR.)-Dry hills or
rarely swamps, nearly throughout N. A.,
east of the Great Plains.-The foliage is
strong scented. The durable heart-wood '
is used in cabinet work and especially for
lead-pencils. The cones are much eaten
by birds and the seeds thus widely dis-
tributed. This species reaches its maximum
development in our region, forming pure
forest stands, in the so-called Cedar glades,
in the Interior Low Plateau province.
2. S. silicicola Small. Tree similar to S.
virginiana in habit, but with shorter and
rather thicker leaves, the relatively blunt apex closely appressed: staminate
ament 4-5 mm. long: cone ovoid or ellipsoid-ovoid, 3-4 mm. long. [S. bar-
badensis (Fl. SE. U.S.)]-(SOUTHERN RED-CEDAR.)-Sand and clay soil, Coastal
Plain, Fla. to Tex. and S. C.-(W. I.)-With the same qualities and a source
of the same products as the preceding. The natural supply has been ex-
hausted through the manufacture of pencil wood.
FAMILY 3. TAXACEAE YEW FAMILY
Evergreen shrubs or trees, mostly destitute of resin, the buds scaly.
Leaves distichously spreading: blades narrow, entire. Staminate ament
mostly few-flowered, with scaly involucres. Ovulate ament most 1-flow-
ered, the carpellary scale wanting. Cone baccate or drupaceous, wholly
or partially enclosed by a pulpy cup-like aril.-About 12 genera, widely
distributed. Many kinds are used in ornamental horticulture.
Ovulate flowers usually 2 together: ovule borne in a cup: seed enclosed in the
accrescent cup: endosperm channeled: pollen-sacs 4. 1. TUMION.
Ovulate flowers usually solitary: ovule borne in a cup: seed surrounded
by the accrescent cup: endosperm even: pollen-sacs more than 4. 2. TAxUs.
1. TUMION Raf. Trees. Leaves rigid. Staminate ament with 4 pollen-
sacs under each scale. Ovulate ament usually with 2 ovules. Seed baccate, the
pericarp fleshy. [Torreya Arn.]-Besides the following, there are three other
species, one in California and two in eastern Asia.
1. T. taxifolium (Arn.) Greene. Tree be-
coming 18 m. tall, with a disagreeable odor
when bruised: leaf-blades linear, 1.5-3 cm.
long, firm-tipped: staminate ament 5-8
mm. long: seed globose-ellipsoid or some-
what obovoid, 3-4 cm. long, glaucous.
[Torreya taxifolia Am.]--(STINKING-CE- /
DAR. TORREYA.)-Bluffs and woods along /
the Apalachicola River, and tributary I
streams, Fla. and adj. Ga.-Spr.-Limited
in distribution, but often plentiful where it
grows. The wood is durable, and many of
the better specimens have been destroyed
for making fence-posts. The seeds are a
favorite food of wild rodents. The heartwood is pale-yellow.
2. TAXUS [Tourn.] L. Diffuse shrubs, or trees. Leaves leathery. Stami-
nate ament with mostly 6-8 pollen-sacs under each scale. Ovulate ament with
1 ovule each. Seed nut-like, surrounded by the pulpy aril, except the apex.-
About 6 species, of wide geographic distribution. A shrubby one occurs in
NE N. A. and may extend into NW N. C., and an arboreous kind ranges west
of the continental divide. The European
species was formerly much used in ecclesias-
tical ceremonies, and much superstition was
associated with the tree.-YEWS.
1. T. floridana Nutt. Tree becoming 6
m. tall, pleasant-scented when bruised:
leaf-blades narrowly linear, 1-2 cm. long,
sharply apiculate: aril light-red, 6-10 mm.
long, the seed ovoid, 5-7 mm. long.-(YEW.
FLORIDA-YEW.)-Bluffs and woods along the
Apalachicola River, and tributary streams,
Fla.-Spr.-Less common than TORREYA.
On account of its smaller size, limited dis-
tribution and comparative scarcity, it has
not been used economically. The heart-wood is light-brown.
CLASS 2. ANGIOSPERMAE SEED-POD PLANTS
Carpel or pistil with a closed cavity within which the ovules
are borne and the seeds mature.
SUBCLASS 1. MONOCOTYLEDONES MONOCOTYLS
Stem consisting of a ground-mass of soft tissue in which
bundles of wood-cells are irregularly placed. Early leaves alter-
nate. This subclass embraces one-fourth of the living seed-plants.
ORDER PANDANALES PANDANAL ORDER
Perennial, aquatic or marsh herbs, with elongate rootstocks. Leaves
with narrow blades. Flowers in narrow racemes or globular spikes.
Perianth of scales or bristles. Androecium of 2-7 stamens. Gynoecium
1- or 2-carpellary. Fruit nut-like.
Racemes cylindric: perianth of bristles. Fam. 1. TYPHACEAE.
Spikes (heads) globular: perianth of scales. Fam. 2. SPARGANIACEAE.
FAMILY 1. TYPHACEAE CAT-TAIL FAMILY
Plants erect. Raceme spike-like, solitary and terminal, subtended by
deciduous bracts, the staminate portion uppermost. Perianth of bristles.
Pistil stipitate: stigma narrow, spatulate, elliptic, or rhomboidal.-A fam-
ily of uncertain relationship. Consists of the following genus.
1. TYPHA [Tourn.] L. Erect herbs with sheathed stems. Leaves erect,
with linear blades. Raceme cylindric, the pistillate portion brown.-About 12
species of tropical and temperate regions. Represented in our range by 2
species, widely distributed.-Sum.-fall.-CAT-TAILs. REED-MACES. COOPER'S
REEDS. CAT-O '-NINE-TAILS.-The rootstocks were an aboriginal food.
Raceme with staminate and pistillate portions usually separate: pollen of simple
grains :pedicels of the mature pistillate raceme short, rigid, 1
mm. long or less. 1. T. angustifolia.
Raceme with staminate and pistillate portions usually contig-
uous: pollen grains in 4's: pedicels of the pistillate raceme
bristle-like, 2-3 mm. long. 2. T. latifolia.
1. T. angustifolia L. Stem slender, 1.5-3 m. tall: leaf-blades 5-15 mm. wide:
raceme light-brown, the pistillate portion 0.5-2 cm. thick, separated from the
staminate: stigma narrow: nutlet terete.
[T. domingensis Pers.]-Marshes, river-
shores, and ditches, nearly throughout N.
A., but best developed near the coast.-
(W. I., Mex., C. A., S. A., Eurasia.)-The
leaves are used for making mats and the
hairs of the fruits to stuff pillows and
2. T. latifolia L. Stem about 1-2.5 m.
tall: leaf-blades 10-25 mm. wide: raceme
dark-brown or black, the pistillate portion
2.5-3.5 cm. thick, contiguous to the sfami-
nate: stigma spatulate or rhomboidal: nut-
let furrowed.-Shores of lakes, ponds, and rivers, and marshes, nearly through-
out U. S. and Can.-(Eurasia.)-Used for the same purposes as the preceding.
FAMILY 2. SPARGANIACEAE-BUR-REED FAMILY
Plants erect, or rarely floating. Spikes globular, borne in racemes or
panicles, or spicate, their bracts persistent. Perianth of scales. Pistil
sessile: stigma subulate, lanceolate, elliptic, or linear. Fruit an achene.
Related to the Typhaceae, but with less modified flower-parts. Comprises
the following genus.
1. SPARGANIUM [Tourn.] L. Plants growing in low grounds, marshes, or
deep water. Stem not sheathed. Leaves erect and triangular-keeled at the
base or floating and flat.-About 24 species in temperate and boreal regions.-
A dozen species additional to those described below occur elsewhere in North
Achene fusiform, the body stalked: fruit-producing flowers pedi-
Achene obovoid or obpyramidal, sessile: fruit-producing flowers
1. S. americanum.
2. S. eurycarpum.
1. S. americanum Nutt. Plant 2-8 dm. tall, simple or branched: staminate
heads mostly less than 1 cm. thick: fruit-head 1-2 cm. thick: achene-body 6-7
mm. long, narrowed at the apex, stipitate.
[S. simplex (Chapm. Fl.)]-River-shores,
borders of lakes, and ponds, various prov-
inces, Fla. to Okla., Minn., and Newf.
Plants with branched inflorescence have been
referred to S. androcladum.
2. S. eurycarpum Engelm. Plant 8-20
dm. tall: staminate head about 1 cm. thick:
fruit-head 2.5 cm. thick: achene-body 7-8
mm. long, rounded or depressed at the apex,
sessile.-Marshes, stream-banks, and pools,
various provinces, Fla. to Calif., B. C., and
Newf.-This is a very vigorous plant. It
frequently fills whole ponds and streams, the dense growth of leaves resem-
bling species of iris or of sweet-flag (Acorus).
ORDER NAIADALES NAIADAL ORDER
Perennial aquatic or marsh herbs. Leaves various, sometimes mere
phyllodia. Flowers usually symmetric. Perianth wanting or imperfect.
Androecium usually of 1-4 stamens. Gynoecium simple or several-car-
Gynoecium of distinct carpels.
Gynoecium of one carpel, or of united carpels.
Staminate and pistillate flowers borne alternately
on a one-sided spadix, laterally attached.
Staminate and pistillate flowers borne in the leaf-
Staminate flower consisting of 2 anthers termin-
ating an elongate pedicel: perianth wanting:
stigmas filiform: caulescent plants with en-
Staminate flower sessile or nearly so, consisting
of an anther surrounded by the perianth:
stigmas subulate: caulescent plants with
spiny toothed leaf-blades.
Fam. 1. ZANNICHELLIACEAE.
Fam. 2. ZOSTERACEAE.
Fam. 3. CYMODOCEACEAE.
Fam. 4. NAIADACEAE.
FAMILY 1. ZANNICHELLIACEAE PONDWEED FAMILY
Aquatic caulescent herbs. Leaves alternate, filiform or with broad entire
blades. Flowers perfect or monoecious, in spikes or clusters from a spathe.
Androecium of 1 or mostly 2-4 distinct stamens. Gynoecium of several
distinct carpels. Fruit a cluster or spike of drupelets.-Five genera and
about 80 species, most abundant in temperate regions.
Flowers monoecious, axillary: leaves opposite. Tribe I. ZANNICHELLIEAE.
Flowers perfect, borne in stalked clusters or spikes: leaves al-
ternate. Tribe II. RUPPIEAE.
Submerged herbs, the very slender leaves with membranous
Stamens 2 or sometimes solitary, the connective without ap-
pendages: drupelet manifestly stipitate.
Stamens 4, the connective with dilated appendages: drupelet
1. ZANNICHELLIA [Mich.] L. Delicate herbs of fresh or brackish
water. Leaves with narrow blades and inconspicuous bases. Flowers mo-
noecious: staminate with 1 stamen: pistil-
late with 2-6 carpels together. Drupelets
clustered, curved, crested.-Two or three
species, widely distributed.
1. Z. palustris L. Stem 2-7 dm. long: leaves
2-7 cm. long, acute: drupelets 2-4, or
sometimes 6, together, the body 2-4 mm.
long, short stipitate.--(HORNED-PONDWEED.)
-Ponds, ditches, and pools, throughout
U. S. and S Can.-(W. I., Mex., C. A.,
O. W.)-Spr.-sum.-Often in dense mats
just beneath the surface of the water.
2. RUPPIA L. Delicate herbs of salt or brackish water. Leaves with
slender blades and conspicuous bases. Flowers perfect. Stamens 2. Carpels 4.
Drupelets clustered, oblique, crestless.-Three
or four species, very widely distributed.
1. R. maritima L. Stem 3-10 dm. long:
leaves 2.5-10 cm. long, capillary at the
apex: drupelets few, the body ovoid, gib-
bous at the base, long-stipitate.-(DITCH-
GRASS. TASSEL-PONDWEED. SEA-GRASS.)-
Shallow water, throughout N. A., except
the extreme N.-(W. I., Mex., C. A., S. A.,
O. W.)-Sum.-fall.-Commonly in exten-
sive dense masses just beneath the surface
of the water. In the extreme southern
Coastal Plain the plant may be found in the winter.
3. POTAMOGETON [Tourn.] L. Herbs growing mostly in fresh water.
Leaves various, the submerged and floating mainly different. Flowers perfect,
spicate. Stamens 4, with appendaged anthers. Carpels 4. Drupelets 4 to-
gether, spicate, sessile.-About 70 species, widely distributed in temperate
regions.-PONDWEEDS. FISHWEEDS.-Both the submerged and the floating
kinds often occur in such dense masses that navigation by small boats is
seriously impeded. Plants are sometimes collected en masse and used as fer-
tilizer. Our plants usually flower in sum.
Stipules axillary, free from the leaf.
Plant with both submerged and floating leaves.
Submerged leaves without blades.
Floating leaves with ovate or oval blades subcordate or rounded at the
base: flowering spikes 3-6 cm. long, 5-6 mm.
thick. 1. P. natans.
Floating leaves with narrowly elliptic blades acute
at both ends: flowering spikes 1-2 cm. long,
2.5-4 mm. thick. 2. P. floridanus.
Submerged leaves with normal blades.
Blades of submerged leaves of 2 forms.
Blade of the floating leaves cordate at the
base: druplet-beak erect. 3. P. pulcher.
Blade of the floating leaves rounded at the
base: drupelet-beak oblique.
Blades of submerged leaves all alike. 4. P. amplifolius.
Submerged leaves with linear or nearly linear
Leaf-blades with coarse cellular reticulation
in the middle. 5. P. epihydrus.
Leaf-blades with inconspicuous cellular
reticulation. 6. P. heterophyllus.
Submerged leaves with lanceolate or oblanceo-
Leaf-blades distinctly petioled. 7. P. fluitans.
Leaf-blades sessile or nearly so. S. P. angustifolius.
Plant with submerged leaves only.
Blade short-petioled or nearly sessile. 9. P. Zucens.
Blade clasping the stem. 10. P. perfoliatus.
Leaf-blades linear or filiform.
Blade 1-nerved. 11. P. Curtissii.
Drupelet crested: plants without propagating
buds or glands. 12. P. foliosus.
Drupelet crestless: plants with both propa-
gating buds and glands. 13. P. pusillus.
Stipules adnate to the blades or to the petioles of the sub-
Plant with both submerged and floating leaves: drupelet
crested. 14. P. diversifolius.
Plant with submerged leaves only: drupelet crestless. 15. P. pectinatus.
1. P. natans L. Leaves of 2 kinds, the submerged phyllodia, the floating
ones with ovate or oval blades 4-9 cm. long, rounded or subeordate at the base:
anther notched at the apex: drupelet obo-
void, 4-4.5 mm. long, scarcely keeled.-
Still water and slow streams, various prov-
inces, Tenn. to Calif., B. C., and N. S.-
2. P. floridanus Small. Smaller than P.
natans: floating leaves with narrowly ellip-
tic blades 4-7 cm. long, acute at both ends:
anther apiculate at the apex: drupelet
smaller than in P. natans.-Blackwater
River, W Fla.
3. P. pulcher Tuckerm. Leaves of 3 kinds,
the lower submerged ones leathery, the
blades spatulate to ovate, the upper submerged ones narrower, flimsy, the
floating leaves with leathery ovate or orbicular-ovate, cordate blades: drupelet
turgid, 4-4.5 mm. long, 3-keeled.--(HEARTLEAF-PONDWEED.)-Ponds, various
provinces, Fla. to Ark., B. C., and Me.
4. P. amplifolius Tuckerm. Leaves of 3 kinds, the lower submerged ones with
lanceolate blades acute at each end, the upper submerged ones mostly smaller
than the lower ones; blades elliptic to oval, the floating leaves with thick ovate
or oval blades rounded at the base: drupelet turgid, 4-5 mm. long, the middle
keel prominent.-Streams and ponds, various provinces, Fla. to Ark., Calif.,
B. C., and N. S.
5. P. epihydrus Raf. Leaves of 2 kinds, the submerged with linear 5-nerved
blades, the floating ones with elliptic or obovate blades 3-8 cm. long: drupelet
globose-obovoid, 2.5-3 mm. long, the middle keel sharp. [P. pennsylvanicus
Willd., P. Nuttallii Cham. & Schlecht.]-Ponds and streams, various provinces,
S. C. to B. C. and Newf.
6. P. heterophyllus Schreb. Leaves of 2 kinds, the submerged narrowed up-
ward, inconspicuously reticulate, the floating ones with oval or elliptic blades
1.5-4 cm. long, abruptly pointed: drupelet 1.5-3 mm. long, indistinctly 3-
keeled.-Still or flowing water, throughout U. S. and S Can.-(W. I., Mex.,
7. P. fluitans Roth. Leaves of 2 kinds, the submerged long-petioled, with
elongate blades, the floating ones with elliptic, sometimes narrowly so, long-
petioled blades 4-15 cm. long, usually acute: drupelet 3.5-4 mm. long, the
middle keel prominent. [P. americanus Cham. & Schlecht., P. lonchites Tuck-
erm.]-Streams and ponds, various provinces, Fla. to Calif., B. C., and N. B.-
(W. I., Mex., O. W.)
8. P. angustifolius Berch. & Presl. Leaves of 2 kinds, the submerged with
blades 5-15 cm. long, the floating ones with elliptic, nearly sessile blades 3-10
cm. long: drupelet 2.5-3.5 mm. long, 3-keeled, abruptly pointed. [P. Zizii
Roth.]-Lakes and streams, various provinces, Fla. to Tex., Calif., and Me.
-(Mex., C. A., O. W.)
9. P. lucens L. Leaves of 1 kind, all submerged; blades elliptic or lanceolate,
or oval above, 5-20 cm. long, acute or acuminate and often serrulate at the
apex, nearly sessile: drupelet 3 mm. long, blunt-tipped.-(CORNSTALK-POND-
WEED.)-Ponds, various provinces, Fla. to Tex., Calif., and N. S.-(W. I.,
Mex., O. W.)
10. P. perfoliatus L. Leaves submerged; blades suborbicular to ovate or
lanceolate, 2-4 cm. long, usually obtuse and serrulate at the apex, cordate-
perfoliate: drupelet 2.5-3 mm. long, obscurely 3-keeled.-Slow rivers and
ponds, various provinces, Fla. to Tex., Minn., and Newf.-(Eu.)
11. P. Curtissii Morong. Leaves submerged; blades linear-filiform, 1-4 cm.
long, 1-ribbed, hair-tipped: drupelet not seen.-Tidal creeks, Blackwater River
region, W Fla.
12. P. foliosus Raf. Leaves very many, submerged; blades linear or filiform,
1.5-5 cm. long, 3-ribbed, acute: drupelet 1.5-2 mm. long, the middle keel
crest-like. [P. pauciflorus Pursh.]-Streams and ponds, various provinces,
Fla. to Calif., B. C., and N. B.-(W. I., Mex.)
13. P. pusillus L. Leaves numerous, submerged; blades linear or linear-
filiform, 2-8 cm. long, 3-ribbed, acute: drupelet 1.5-2 mm. long, the middle
keel not crest-like, or obsolete.-Slow streams and ponds, various provinces,
Ala. to Calif., B. C., N. S., and N. C.-(Mex., Eurasia.)
14. P. diversifolius Raf. Leaves of 2 kinds, the submerged linear-setaceous,
the floating ones elliptic, oval, or elliptic-lanceolate, 1-2.5 cm. long: drupelet
about 1 mm. long, the middle keel crest-like. [P. hybridus Michx.]-Ponds
and still water, various provinces, Fla. to Tex., Calif., and Me.-(W. I., Mex.)
15. P. pectinatus L. Leaves of 1 kind, all submerged, setaceous or filiform,
2-15 cm. long: drupelet 1.5 mm. long, crestless.-Still water or streams, various
provinces, Fla. to Tex., Calif.,'B. C. and Que.-(W. I., 0. W.)
FAMILY 2. ZOSTERACEAE EEL-GRASS FAMILY
Marine herbs. Leaves alternate: blades narrow, the base inflated.
Flowers monoecious, alternating on a flat spadix; staminate a sessile
anther; pistillate an ovary with a style and two capillary stigmas. Fruit
utricular.-Consists of 2 genera and about 8 species of wide distribution
in coastal regions.
1. ZOSTERA L. Plants submerged or
floating. Leaf-blades elongate. Spathe
thin-edged.-About 8 species in both the
Old World and the New.
1. Z. marina L. Leaf-blades linear, 3.5-5
mm. wide: spadix 2.5-6.5 cm. long:
seed about 20-ribbed.-(GRAss-WRACK. EEL-
GRASS.)--Streams, bays, and ditches along
the coast, Fla. to Newf.; also on Pacif.
coast.-(0. W.)-It occurs only in salt
water.-Z. minor has been reported in our
region, but imperfect material of the next
following species has been mistaken for it.
FAMILY 3. CYMODOCEACEAE MANATEE-GRASS FAMILY
Submerged herbs with jointed rootstocks. Leaves clustered at the
nodes or on short branches each with a sheath and a narrow blade. Flowers
monoecious or dioecious. Perianth wanting. Androecium a pair of anthers
terminating a long stalk. Gynoecium of 2 united carpels, terminating in a
style and 2 elongate stigmas, or of 1 carpel. Fruit an oblique nutlet.-
Comprises 2 genera and 10 species, widely distributed.
Anthers equally attached to the stalk: stigmas 2: leaf-blade
terete or nearly so. 1. CYMODOCEA.
Anthers unequally attached to the stalk: stigma 1: leaf-blade
flat. 2. HALODULE.
1. CYMODOCEA Koenig. Rootstock
elongate. Leaves terete or half-terete above
the sheaths. Flowers hidden in the leaf-
sheaths, or the staminate long-exserted.--
Seven or eight species, in tropical regions.
1. C. manatorum Aschers. Plant growing
on sandy bottoms, the short stems arising \
from the nodes of the rootstock: leaf-blades
narrowly linear, 5-25 cm. long: nutlet 6-7
mm. long, short-stipitate, prominently
and bays, Fla. to La.-(W. I.)-All year.
Seldom seen unless dredged up or blown ashore during storms.
2. HALODULE Endl. Rootstock elongate. Leaves flat above the
sheaths. Flowers borne in the leaf-sheaths or the staminate long-exserted.
-Two species, one in the Old World and
one in the New.
1. H. Wrightii Aschers. Plant growing
on sandy bottoms, the short stems aris-
ing from the nodes of the rootstock: leaf-
blades narrowly linear, 3-40 cm. long:
nutlets sessile.-Bays and creeks along
the coast, southern Fla., particularly on
the Reef.--(W. I.)-All year.-Grows alone
or in company with Cymodocea. Both
these plants are commonly associated
with the turtle-grass, Thalassia, on sandy
FAMILY 4. NAIADACEAE NAIAD FAMILY
Mostly fresh-water herbs. Leaves mainly opposite: blades mostly
toothed, the bases dilated. Flowers dioecious, axillary: staminate, a double
perianth and a single stamen: pistillate, a gynoecium consisting of an
ovary, a style, and 2 or 3 stigmas. Fruit drupaceous.-Consists of the fol-
1. NAIAS L. Submerged plants with usually much-branched stems.
Leaves numerous, the margins prominently or inconspicuously toothed.-About
10 species, collectively almost cosmopolitan.-NAIADS.
Flowers monoecious: internodes and lower surfaces of the
Anther 1-celled: seeds shining. 1. N. flexilis.
Anther 4-celled : seeds reticulated.
.'eaf-margins with minute subulate teeth. 2. N. guadalupensis.
-Jeaf-margins with prominent triangular teeth. 3. N. conferta.
Flowers dioecious: internodes and lower surfaces of the
Leaves about 0.5 mm. wide, with 15-24 marginal teeth:
internodes filiform. 4. N. gracilis.
Leaves about 2 mm. wide, with 6-10 marginal teeth:
internodes stout. 5. N. marina.
1. N. flexilis (Willd.) Rostk. & Schmidt. iStem slender: leaves more numerous,
rather closer together and smaller than in the next following; blade mainly
acuminate: drupelet 3-4 mm. long.-Streams
and ponds, various provinces, S. C. to Tex.,
B. C., and Lab.-(W. I. ? Mex. ? O. W.)-
Sum.-This and some of the following
species are sometimes collected for fertilizer.
Dried en masse it is occasionally used as a I
2. N. guadalupensis (Spreng.) Morong. n
Stem capillary or filiform: leaves 10-26 mm.
long; blade acute: drupelet about 2 mm.
long.-Ponds and lakes, various provinces,
Fla. to Tex., Ore., and Pa.-(W. I., Mex.,
3. N. conferta A. Br. Similar to N. flexilis in habit, but the leaves more
slender; blade with prominently sharp-toothed margins.-Tidal creeks, W Fla.
4. N. gracilis (Morong) Small. Stem filiform, the internodes slightly armed
near the top: leaf-blades slender, acuminate: drupelet mainly less than 4 mm.
long.-Creeks and ponds, Fla.-All year.
5. N. marina L. Stem stout, the internodes strongly armed throughout: leaf-
blades linear, acute: drupelet mainly over 4 mm. long. [NV. major All.]-
Lakes, rivers, marshes, and salt springs, various provinces, Fla. to Calif.,
Minn., and N. Y.-(W. I., Mex., O. W.)-Sum.
ORDER ALISMALES ALISMAL ORDER
Marsh or aquatic herbs. Leaves alternate, mere phyllodia, or with
dilated blades. Flowers regular. Perianth of sepals and usually also of
petals. Androecium of 3-6 stamens or more. Gynoecium of 3-many
Petals nearly similar to the sepals: carpels co-
herent. Fam. 1. SCHEUCHZERIACEAE.
Petals very different from the sepals: carpels not
coherent. Fam. 2. ALISMACEAE.
FAMILY 1. SCHEUCHZERIACEAE -ARROW-GRASS FAMILY
Perennial herbs. Leaves narrow or slender above the dilated bases.
Flowers perfect, in spikes or racemes. Perianth herbaceous. &ynoecium
3-6-carpellary. Style wanting or obsolete. Fruit 3-6 turgid carpels.-
Four genera and about 10 species of wide geographic distribution.
1. TRIGLOCHIN L. Acaulescent herbs, the perianth inconspicuous.-
Nine species, in subarctic and temperate regions. Two species, additional to
the following, occupy similar habitats in
North America north of our range.
1. T. striata R. & P. Plants glabrous:
leaves 2-3 dm. long, attenuate: raceme 2-15
cm. long: sepals ovate or oval, less than 1
mm. long, greenish or light-yellow: fruit
1.5-2 mm. in diameter, each carpel 3-ribbed.
[T. triandra Michx.]-(ARROW-GRASS.)-
Salt-marshes, river-shores, and edges of
lakes, mostly near the coast, Fla. to La. and
Md.; also Calif.-(Mex., S. A.)-Sum.-fall,
or all year S.-Reaches its best development
in the coastwide marshes. It is rare in the Florida lake region.
FAMILY 2. ALISMACEAE WATER-PLANTAIN FAMILY
Annual or perennial herbs. Leaves basal, the blades flat, often with
basal lobes, or mere phyllodia. Flowers perfect, monoecious, or dioecious,
whorled. Sepals herbaceous. Petals tender, white or pink. Gynoecium
of few to many carpels. Style manifest. Fruit a head of flattened or
turgid achenes.-About 14 genera and 75 species, widely distributed in
fresh-water swamps and marshes.
Carpels borne in one series: achenes verticillate.
Carpels borne in several spiral series: achenes capitate.
Flowering stem much branched, the pedicels very slender and
Flowers all perfect.
Style not apical: fruit-head not echinate: achene turgid,
beakless or only obscurely beaked.
Style apical: fruit-head echinate: achene flat, promi-
Flowers polygamous or dioecious, or monoecious-the lower
flowers of the inflorescence perfect or pistillate, the
upper ones staminate.
Lower flowers of the inflorescence perfect.
Lower flowers of the inflorescence pistillate.
1. ALISMA L. Leaves without basal lobes. Flowers perfect, in com-
pound panicles. Stamens mostly 6. Achenes in 1 whorl.-About 10 species,
mostly in temperate and tropical regions. r-
1. A. subcordatum Raf. Leaves erect;
blade entire, 3-15 cm. long, long-petioled:
scape 1-10 dm. tall, the branches, or pedi-
cels, whorled in 3's to 10's: sepals obtuse:
petals 1-2 mm. long: fruit-heads depressed,
3.5-4.5 mm. wide: achene 1.5-2 mm. long.
[A. Plantago (Chapm. Fl.)]-(WATER-
PLANTAIN.)-Swamps, ditches, and shallow
water, various provinces, Fla. to Tex., Minn.,
2. HELANTHIUM Engelm. Leaves without basal lobes, the blades nar-
row. Flowers perfect, borne in racemes. Stamens 6 or 9. Achenes borne
in an inconspicuous naked head.-Two
species, one in Cuba and the following.
1. H. parvulum (Engelm.) Britton. Leaves
lax; blade linear or linear-elliptic, 1-3 cm.
long: scape 3-11 cm. tall, with a terminal
whorl of 2-8 flowers: petals 1.5-2 mm. long:
fruit-head 3-4 mm. thick: achene barely 1
mm. long. [Echinodorus parvulus Engelm.]
-Muddy places or shallow water, various
provinces, Fla. to Tex., Minn., and Mass.-
(W. I., 2Mex.)--Spr.-fall.
3. ECHINODORUS L. C. Rich. Leaves with rounded basal lobes. Flow-
ers perfect, in racemes or panicles. Stamens 12-30. Achenes borne in a
bristly naked head.-About 15 species, all but the following mostly tropical
American.-Spr.-sum.-BUR-HEADS. MUD-BABIES. CREEPING WATER-PLANTAINS.
Flowers, and fruit-heads, borne on pliable curved pedicels: style shorter than the
ovary: achene-beak about 1 as long as the body. 1. E. radicans.
Flowers, and fruit-heads, borne on stiff spreading pedicels: style
longer than the ovary: achene-beak fully 1/ as long as the
body. 2. E. cordifolius.
1. E. radicans (Nutt.) Engelm. Stem creeping near the base: leaf-blades
ovate or elliptic, 5-20 cm. long: scape often creeping, the flower-whorls remote:
petals about 6 mm. long: fruit-head 7-8 mm.
thick: achene 2 mm. long, short-beaked.-
Pond-margins and ditches, various provinces,
Fla. to Tex., Calif., Kans., and D. C.
2. E. cordifolius (L.) Griseb. Stem erect
or ascending: leaf-blades lanceolate to
broadly ovate, 4-20 cm. long: scape 1-5 dm.
tall, the flower-whorls less remote than in
E. radicans: petals 4-6 mm. long: fruit-
head 4-6 mm. thick: achenes 2.5-3 mm.
long, long-beaked. [E. rostratus Engelm.]-
Swamps, ditches, and ponds, various pro-
vinces, Fla. to Tex., Kans., and Ill.-(W. I., Mex., C. A.)
4. LOPHOTOCARPUS T. Durand. Leaves often with basal lobes, but
variable. Flowers monoecious, the upper ones staminate. Stamens 9-15.
Achenes in a head embraced by the calyx.-
About 7 species, besides the following and
several that range westward to California,
others occur in tropical America.-Sum.-
1. L. calycinus (Engelm.) J. G. Smith.
Leaves with petioles 1.5-4 dm. long: scape
with 2-6 flower-whorls: achene over 2 mm.
long, broad, beaked.-Wet grounds, swamps,
and ponds, various provinces, Ala. to N. M.,
S. Dak., and Del.
5. SAGITTARIA L. Leaves often with basal lobes, sometimes lobeless,
or mere phyllodia. Flowers monoecious or dioecious, the upper ones usually
staminate. Corolla white. Stamens mainly numerous. Achenes numerous or
rarely few, in dense heads.-Comprises about 40 species of wide geographic
distribution. Several species produce edible starchy tubers which were ex-
tensively used by the aborigines.-Mainly sum.-fall, or all year S.-ARRow-
Sepals of the pistillate flowers ultimately lax or reflexed, not accrescent.
Fruit-bearing pedicels reflexed or recurved. I. SUBULATAE.
Fruit-bearing pedicels ascending.
Leaf-blades without basal lobes. II. ANGUSTIFOLIAE.
Leaf-blades with basal lobes. III. LATIFOLIAE.
Sepals of the pistillate flowers accrescent and ultimately
appressed to the fruit-heads. IV. MONTEVIDENSES.
Inflorescence simple, except in robust plants of
S. lorata: phyllodia obtuse or abruptly pointed.
Mud-inhabiting plant with short leaves: filaments
about as long as the afithers: achene long-
beaked. 1. S. subulata.
Aquatic plants with elongate leaves: achene
Leaves with small floating blades: inflores-
cence simple: crests of the achene with
mere shallow undulations.
Leaves elongate ligulate phyllodia: inflores-
cence sometimes branched: crests of the
achene with deep undulations.
Inflorescence branched: phyllodia slenderly attenuate.
Pedicels of the pistillate flowers as long as those of the
staminate ones, or nearly so.
Filament dilated, relatively short.
Leaf-blade terete or 3-sided, often imperfectly
Anther longer than the filament: achene with
several facial wings.
Anther shorter than the filament: achene with
3 low facial ridges.
Achene oval or broadly elliptic.
Beak large, horizontal at the top of the
Beak minute, borne much below the top of
Inflorescence simple: lower bracts ovate,
united to the middle: achene with
lateral ribs or wings.
Inflorescence widely branched : lower
bracts lanceolate, united at the base:
achene without lateral ribs or wings.
Filament not dilated, slender.
Bracts and sepals granular-papillose.
Bracts and sepals ribbed.
Achene more or less falcate, gradually beaked,
the dorsal wing thick and even.
Achene not falcate, abruptly beaked, the dorsal
wing usually thin and crested.
Pedicels of the pistillate flowers very short or nearly
Fruit-head not echinate: achene broadly winged and
short-beaked: anther broadly elliptic, about as long
as the filament.
Fruit-head echinate: achene narrowly winged and
long-beaked: anther suborbicular, shorter than the
Achene minutely or inconspicuously beaked.
Achene prominently long-beaked:
Beak horizontal or nearly so.
Inflorescence-rachis, pedicels, bracts, and sepals
Achene less than 4 mm. long; beak horizontal
or declined, narrow, much smaller than the
body from which it is differentiated: bracts
Achene over 4 mm. long; beak horizontal-
ascending, broad, larger than the body, with
which it is continuous: bracts granular-
Inflorescence-rachis, pedicels, bracts, and sepals
Pistillate pedicel very short: sepals and bracts
Pistillate pedicel elongate: sepals and bracts
Basal lobes of the leaf-blade acute or acumi-
Basal lobes of the leaf-blade rounded.
Robust plant: leaf-blades 1-5 dm. long and wide: scape
up to 1 m. tall.
2. S. stagnorum.
3. S. lorata.
4. S. filiformis.
5. S. platyphylla.
6. S. teres.
7. S. isoetiformis.
8. S. cycloptera.
9. S. Mohrii.
10. S. graminea.
11. S. Chapmanii.
12. S. falcata.
13. S. lancifolia.
14. S. angustifolia.
15. S. macrocarpa.
16. S. rigida.
10. S. graminea.
17. S. pubescens.
18. S. ornithorhyncha.
19. S. latifolia.
16. S. rigida.
20. S. viscosa.
21. S. longirostra.
22. S. australis.
23. S. montevidensis.
1. S. subulata (L.) Buch. Leaves erect; blade linear or linear-lanceolate, 2-3
cm. long, or wanting, the phyllodia slender: scape 5-15 cm. tall, with 1 or 2
flower-whorls: achenes relatively few, about
1.5 mm. long, the beak ascending. [S. na-
tans pusilla Chapm.]-Tidal flats and mud,
Coastal Plain and New England Coast,
Fla. to Ala. and Conn.
2. S. stagnorum Small. Leaves few;
blades elliptic to ovate-elliptic 1.5-5 cm.
long, the phyllodia linear, wider than the
petioles: scape with 1-few flower-whorls:
flowers floating: achenes few, about 2 mm.
long, the beak mostly erect. [S. natans
Michx. not Pall.---Shallow ponds, Coastal
Plain, Fla. to Ala. and S. C.
3. S. lorata (Chapm.) Small. Leaves represented by elongate-linear, often
rather broad phyllodia which sometimes are up to 250 cm. long, 3-5-ribbed, at
least in age: scape about as long as the leaves: flower-whorls usually 4-8:
flowers floating: achenes numerous, 2-2.5 mm. long, the beak horizontal.-
Streams and springs, Fla. and adj. Coastal Plain of Ala. and Ga.; perhaps N
along the coast. The plant of the northern states, sometimes referred here,
may represent a different species.-An apparently extremely large form of
S. lorata in the Wakulla River, Fla., has been named S. Kurziana Gliick.
4. S. filiformis J. G. Smith. Leaf-blades wanting: scape 6-12 dm. long, with
several flower-whorls; only 1 or 2 flowers of the lower whorls pistillate, their
pedicels elongate: fruit-head 6-7 mm. thick: achene 1.5 mm. long, about
6-crested, the beak curved up.-Ponds, Coastal Plain, Fla. and Ala.; appar-
ently also in the Carolinas.
5. S. platyphylla (Engelm.) J. G. Smith. Leaf-blades lanceolate, elliptic, or
ovate, 5-15 cm. long: scape 2-5 dm. tall, with 3-8 flower whorls, the flowers
of 2 or 3 lower whorls pistillate, their pedicels very short: fruit-heads fully
10 mm. thick: achenes 2 mm. long, winged, the beak horizontal.-Ponds and
swamps, various provinces, Ala. to Tex., Kans., and Mo.
6. S. teres S. Wats. Leaf-blades narrow and imperfect, or wanting: scape
1.5-4.5 dm. tall, with 1 or rarely 2 or 3 flower-whorls, 1 or 2 flowers of the
lower whorl pistillate: fruit-head 8-12 mm. thick: achene 2 mm. long, un-
evenly crested, the beak nearly erect.-Shallow water, Coastal Plain and New
England Coast, S. C. to Mass.
7. S. isoetiformis J. G. Smith. Leaf-blades wanting or imperfect: scape
7-12 dm. tall, usually with 1 flower whorl: fruit-head about 6 mm. thick:
achene 1 mm. long, dorsally crested, the beak oblique.--Low grounds and sandy
lake-margins, Coastal Plain, Fla. and S Ga.
8. S. cycloptera (J. G. Smith) C. Mohr. Leaf-blades linear or linear-lanceo-
late, 4-15 cm. long, or wanting: scape 2-8 dm. long, mainly with 3-15 flower-
whorls: fruit-head barely 10 mm. thick: achene 1.5 mm. long, the minute beak
ascending.-Swamps, Coastal Plain, Fla. to La. and S. C.
9. S. Mohrii J. G. Smith. Leaf-blades linear to lanceolate, 5-15 cm. long,
sometimes imperfect: scape 4-9 dm. long, with 6-8 flower-whorls: fruit-head
6-8 mm. thick: achene 2.5-3.5 mm. long, the large beak horizontal.-Ponds,
Coastal Plain, Fla. to Miss. and Ga.
10. S. graminea Michx. Leaf-blades linear, lanceolate, or elliptic, 5-15 cm.
long, or wanting: scape 1-6 dm. tall, with few or many flower-whorls: fruit-
head less than 10 mm. thick: achene 1.5 mm. long, winged, the minute beak
horizontal.-Mud and ponds, various provinces, Fla. to Tex., Sask., and Newf.
11. S. Chapmanii (J. G. Smith) C. Mohr. Leaf-blades linear or lanceolate,
15-20 cm. long, or wanting: scape 3-5 dm. long, with often many flower-whorls
and paniculate: fruit-head 5 mm. thick: achene 1 mm. long, wingless, the
minute beak lateral.-Ponds and marshes, Coastal Plain, Fla., Ala., and Ga.
12. S. falcata Pursh. Leaf-blades narrowly elliptic, sometimes slightly broad-
est above the middle, or nearly linear, 10-35 cm. long, mainly 3-5 nerved:
pedicels of the pistillate flowers relatively short, their bracts of an ovate type:
achene about 2 mm. long.-Low grounds and marshes, Coastal Plain, Fla. to
Tex. and Del.-(Mex.)
13. S. lancifolia L. Leaf-blades elliptic or nearly so to narrowly elliptic-
lanceolate, 30-60 cm. long, mainly 5-9-nerved: pedicels of pistillate flowers
relatively long, their bracts of a lanceolate type: achene 2.5-3 mm. long.-
Swamps, pools, and low river-banks, Coastal Plain, Fla. to Tex.-(W. I., Mex.,
C. A., S. A.)-Very variable in size, but at its best it is the giant of our arrow-
heads. On the Florida prairies and marshes the leaves and flower-stalks often
grow higher than one's head. Used medicinally by the Seminoles in cases of
shock following alligator bite.
14. S. angustifolia Lindl. Leaf-blades linear or nearly so, sometimes very
narrow, 9-40 cm. long: scape as long as the leaves or longer, usually simple,
with several flower-whorls, their bracts of a lanceolate type: fruit-head 1-1.5
cm. thick: achene 2-2.5 mm. long, abruptly narrowed into the minute beak,
the dorsal wing usually crested.-Low grounds and swamps, Coastal Plain, Ga.
to La.-(W. I., Mex., C. A., S. A.)
15. S. macrocarpa J. G. Smith. Leaf-blades linear or linear-lanceolate, 5-7
cm. long: scape 2-4.5 dm. tall, with 3-5 flower-whorls, the flowers of the lowest
whorl or the 2 lower whorls pistillate: fruit-head 10-12 inm. thick: achene 3 mm.
long, winged, the beak ascending.-Pond-margins and streams, Coastal Plain,
S. C. and N. C.
16. S. rigida Pursh. Leaf-blades linear to broadly ovate, individually with
basal lobes, 5-20 cm. long: scape weak, 1-8 dm. long, with 5-9 flower-whorls:
fruit-head 8-15 mm. thick, sessile or nearly so: achene 3-4 mm. long, winged,
the beak ascending.--(STIFF-ARROWHEAD.)--Swamps and running water, various
provinces, Tenn. to Nebr., Minn., Que., and N. J.
17. S. pubescens Muhl. Leaf-blades 8-25 cm. long, with the terminal lobe
more rounded than in no. 20, puberulent or hirsute: scape 3-6 dm. tall:
pedicels of pistillate flowers about as long as the obtuse bracts or slightly
longer: sepals not accrescent: fruit-head 8-15 mm. thick: achene 2-3 mm. long,
the beak horizontal or somewhat declined.-Meadows, spring-runs, and marshes,
Coastal Plain and rarely adj. provinces, Fla. to Ala., Tenn., Pa., and N. J.
18. S. ornithorhyncha Small. Leaf-blades 9-17 cm. long, hastate, the terminal
lobe slightly acuminate, the basal lobes as long as the terminal one or nearly
so: scape 7-9 dm. tall: pedicels of the pistillate flowers much longer than the
acute or acutish bracts: sepals ovate, obtuse: fruit-heads globular, 1.5-2 cm.
in diameter: achene resembling a bird, 4-6 mm. long, the beak as long as the
achene-body or longer, winged, horizontal-ascending.-Swamps, Coastal Plain,
19. S. latifolia Willd. Leaf-blades broad, 15-40 cm. long, glabrous, the basal
lobes narrower and rather shorter than the terminal one: scape 3-6 dm. tall:
pedicels of pistillate flowers much longer than the acute bracts: fruit-head
15-30 mm. thick: achene about 3 mm. long, the beak ascending or recurved.
[S. variabilis Engelm.]-(ARROWLEAF. DUCK-POTATO. WAPATO.)-Swamps,
shallow water, and river-banks, various provinces, Fla. to Calif., B. C., and N.
B.-(Mex., C. A.)
20. S. viscosa C. Mohr. Leaf-blades 20-35 cm. long, the middle lobe broadly
ovate, the basal lobes shorter, acute or acuminate: scape 5-8 dm. tall, with few
flower-whorls: bracts obtuse: fruit-heads not seen.-Muddy places and marshes,
Coastal Plain, N Fla. and S Ala.
21. S. longirostra (Micheli) J. G. Smith. Leaf-blades 10-25 cm. long, the
terminal lobe broadly ovate, the basal lobes as long but narrower: scape 4-8
cm. tall, with few flower-whorls: bracts acuminate: fruit-heads 12-18 mm.
thick, short-pedicelled: achene 4 mm. long, with facial wings, the dorsal wing
partially crenate, the beak erect.-Pond-margins and streams, Coastal Plain
and rarely adj. provinces, Fla. to Ark., Pa., and N. J.
22. S. australis (J. G. Smith) Small. Leaf-blades 8-10 cm. long, the terminal
lobe very broad, the basal lobes shorter, obtuse: scape 4-5 dm. tall, with 4-6
flower-whorls: fruit-heads fully 10 mm. thick: achene 3-3.5 mm. long, with
facial wings, the dorsal wing undulate, the beak curved over the crest.-Low
grounds, Appalachian Plateau, N Ala.
23. S. montevidensis C. & S. Leaf-blades 1-5 dm. long, the basal lobes nar-
rower and shorter than the ovate terminal one: scape very stout, about as tall as
the leaves, the pedicels relatively short: fruit-heads 15-30 mm. thick: achene
2-3 mm. long, the slender beak oblique.-(GIANT-ARROWLEAF.)-Low grounds
and swamps, Coastal Plain, Fla. to Ala. and N. C.; also Calif. Nat. of S. A.
ORDER HYDROCHARITALES HYDROCHARITAL ORDER
Perennial aquatic herbs, with rootstocks. Leaves usually with blades.
Flowers monoecious or dioecious, or rarely perfect, from spathes. Perianth
double, or the corolla wanting. Androecium of 1-12 stamens. Gynoecium
3-15-carpellary. Ovary inferior. Fruits capsular or baccate.
Gynoecium 3-carpellary, or rarely 2-, 4- or 5-carpellary: ovary 1-celled, with 3, or
rarely with 2, 4 or 5 parietal placentae: stigmas
usually 3. Fam. 1. ELODEACEAE.
Gynoecium 6-9 carpellary: ovary 6-9-celled: stigmas
6-9. Fam. 2. HYDROCHARITACEAE.
FAMILY 1. ELODEACEAE -TAPE-GRASS FAMILY
Plants with leafy stems, or leaves basal, often greatly elongate. Gyno-
ecium 2-5-carpellary, the ovary 1-celled.-Comprises 6 genera and about
24 species, widely distributed in warm regions.
Staminate flower with 1-3 stamens: plant with horizontal rootstocks.
Leaves opposite on short horizontal stems; blade broad, more or less petioled:
stigmas filiform: pollen filiform : marine plant. 1. HALOPHILA.
Leaves spiral, but in a basal cluster; blade linear, without
a petiole: stigmas short and broad: pollen spheroidal:
fresh water plant. 2. VALLISNERIA.
Staminate flower with 9 stamens: fresh water plant with float-
ing stems and whorled leaves. 3. PHILOTRIA.
1. HALOPHILA Thouars. Marine submerged herbs, with short branches
arising from the rootstock. Leaves opposite or whorled, the lower ones often
scale-like. Flowers dioecious or monoecious, the staminate pedicelled, the
pistillate sessile in the spathe, flask-shaped. Fruit short, included in the
spathe.-About 6 species, mostly circumtropical.-SEA-GRASSES-The plants
creep on the sea-bottom, in shallow water, or at considerable depths when
the water is clear. Their habit is somewhat suggestive of marine algae of
the genus Caulerpa; often found washed ashore after storms.
Leaves 1 or 2 at the tip of the branches; blades evidently
serrulate, on filiform petioles: capsule short-beaked. 1. H. Baillonis.
Leaves 3-7 at the tips of the branches; blades ciliate or
ciliolate and obscurely serrulate, sessile or with stout
short petiole-like bases: capsule long-beaked. 2. H. Engelmannii.
1. H. Baillonis Aschers. Plant with a thread-like rootstock, the branches
short, usually very short or obsolete: leaves opposite, blades oblong, linear-
oblong, or spatulate, mostly 1-2.5 mm. long,
thin, often minutely pubescent, especially
when young, with the lateral veins indis-
tinct or obscure, slender-petioled: capsule
ellipsoid or ovoid-ellipsoid, 3-3.5 mm. long.
-Sandy or marly bottoms on Reef about
the Florida Keys. J
2. H. Engelmannii Aschers. Plant with a
cord-like rootstock; the branches stoutish,
mostly 2-6 cm. long: leaves mostly whorled
at the tips-of the stem and branches; blades
linear, elliptic, or oblanceolate, 1-3 cm. long,
thick, glabrous, sharply serrulate, evidently
3-veined, sessile or with short petiole-like :'
bases: capsule ovoid or globose-ovoid, 2.5-3
mm. long.-Bays and creeks, coast of Fla. and open waters of the Fla. Reef.
2. VALLISNERIA [Mich.] L. Fresh-water herbs. Leaves basal with
greatly elongate ribbon-like blades. Flowers dioecious, the staminate numerous,
crowded on a spadix; they break away from their short stalks and float on the
surface of the water where they shed their pollen about the pistillate flowers
which have been raised to the surface by the rapid growth of the pedicels.
Pistillate flowers few, each solitary at the end of an elongate spiral scape.
Fruit subtended by the spathe.-Two species, both represented in our range,
the first one also in the Old World.-EEL-GRASSES. TAPE-GRASSES. WATER-
CELERIES.-Plants with their long leaves and pistillate flowers usually partly
Stigmas cleft for less than half their length: sepals of the pistillate flowers 2-3
mm. long. 1. V. spiralis.
Stigmas cleft nearly to the base: sepals of the pistillate flowers
5-6 mm. long. 2. V. americana.
1. V. spiralis L. Leaf-blades thin, 3-8 mm. wide, usually denticulate, espe-
pecially near the apex: peduncles of the pistillate flowers 3-6 dm. long, spirally
twisted at maturity: spathe close-fitting,
1-1.5 cm. long: hypanthium 1-2 cm. long
in anthesis: petals minute: capsule slen-
der.-Still and flowing water, various prov-
inces, N. C. to Ind., S. Dak., and N. S.-
(0. W.)-Sum.-fall.-A wide-spread species,
occurring in both the Old World and the
New, but barely entering our range from
2. V. americana Michx. Leaf-blades thick-
ish, 6-20 mm. wide, often denticulate:
peduncles of the pistillate flowers 5-10 dm.
long or more, curved at maturity, but
scarcely spiral; spathe loose, 2-2.5 cm. long: hypanthium 2.5-3 cm. long in
anthesis: petals less than 1/2 as long as the sepals: capsule stout, 7-11 cm.
long.-Creeks, rivers, and lakes, Coastal Plain, Fla. to La.-All year.-A plant
much larger in all its parts than the preceding. Often very luxuriant in
growth. Like the preceding species it is a favorite food of ducks, and perhaps
of other water birds.
3. PHILOTRIA Raf.1 Fresh-water herbs. Leaves cauline, opposite or
whorled. Flowers perfect and with 3 stamens or dioecious or polygamous; the
staminate with 9 stamens detach themselves, arise and float on the surface of
the water and shed their pollen about the pistillate or perfect flowers or reach
the surface by the elongation of their thread-like hypanthia like the pistillate
flowers which are raised to the surface on long stalks; the pistillate similar
and slender-pedicelled. Fruit enclosed by the spathe. [Elodea Michx.]-
About 10 species, natives of America; one naturalized in Europe.-Spr.-sum.
-WATERWEEDS.-The plants of some species are collected locally and applied
to cultivated land as fertilizers.
Staminate spathes not cleft nearly to the base, 1-flowered:
petals less than 5 mm. long or wanting: upper
leaves in whorls of 3.
Leaf-blades 1-5 mm. broad: staminate flowers with the
3 central stamens on a stalk exceeding the other 6 :
pistillate flowers frequent, long-exserted. 1. P. canadenzsis.
Leaf-blades less than 1 mm. broad: staminate flowers
with 9 equal stamens: pistillate flowers unknown. 2. P. linearis.
Staminate spathes cleft nearly to the base, several-flowered:
petals about 1 cm. long; upper leaves in whorls
of 4. 3. P. denisa.
1. P. canadensis (Michx.) Britton. Stem slender, dichotomously branched
lower leaves opposite, with small ovate blades; upper leaves of pistillate plant,
with elliptic to lanceolate-ovate blades, firm,
dark-green, imbricate above; those of stami-
nate plants narrower, even lanceolate-linear,
thinner, scarcely imbricate: staminate spathe
slender at the base, with an inflated ellipsoid
bidentate apex; staminate flower exserted on
a thread-like hypanthium: sepals elliptic,
3.5-5 mm. long; petals white, linear: an-
thers 3 mm. long: pistillate spathe nearly
cylindric, bidentate: pistillate flower long
exserted; sepals 2.2 mm. long; petals white
clawed, spatulate; staminodia 3, acicular:
stigmas 3, ligulate, pink, 2-cleft. [P. Nut-
tallii (Fl. SE. U. S.)]-Ponds, springs, and
streams, various provinces, N. C. and Ala.
to Calif., Wash., and Que.-A related spe-
cies, P. angustifolia, has been reported from Florida in error.
2. P. linearis Rydb. Stem slender: upper leaves with linear, flaccid, pale-
green blades, 5-12 mm. long, not imbricate: staminate spathe as in P. cana-
densis; staminate flower exserted on a thread-like hypanthium: sepals oval,
2.5-4 mm. long: petals white, linear, exceeding the sepals or abortive; anthers
2 mm. long.-Swamps, Interior Low Plateaus, along Cumberland River, near
3. P. densa (Planch.) Small. Stem stout, 2-3 mm. in diameter: leaves very
numerous, densely crowded; blades lanceolate to linear-lanceolate, 1.5-2 cm.
long, 2-5 mm. broad, acuminate, serrulate: spathe of the staminate flowers
1 Prepared with the assistance of Harold St. John.
narrowly conic, about 1 cm. long: sepals green, oval to ovate, 3-4 mm. long:
petals white, 9-11 mm. long: pistillate flowers not seen.-Lakes, Pinellas pen.,
Fla.-Perhaps introduced through cultivated plants.-(S. A.)
FAMILY 2. HYDROCHARITACEAE FROG'S-BIT FAMILY
Plants with leaves in clusters on the rootstocks. Gynoecium 6-9-car-
pellary, the ovary 6-9-celled.-Comprises 8 genera and about 20 species of
temperate and tropical regions.
Flowers dioecious: stamens distinct: anther nearly sessile: leaf not differentiated
into blade and petiole. 1. THALASSIA.
Flowers monoecious: stamens with united filaments: leaf differ-
entiated into blade and petiole. 2. LIMNOBIUM.
1. THALASSIA Banks. Marine herbs. Leaves mere strap-like blades.
Flowers dioecious. Fruit rugose or nearly echinate.-Two species, circum-
1. T. testudinum Koenig & Sims. Leaves
2-5 together; blade linear, 5-30 cm. long:
fruit echinate-pubescent, erect.-(TURTLE-
GRASS. SEA-WEED.)-Bays and coasts, pen.
Fla. and Florida Reef.-(W. I., S. A.)-All
year.-Occurs mainly in vast submarine
fields, often forming a dense turf. The
leaves are washed ashore in vast quantities
and are gathered as "sea weed" for ferti-
lizer. Only during quiet weather, and con-
sequent clear water, can one get an adequate
view of these submarine fields which are
favorite rendezvous for various kinds of fish, turtles, and other marine animals.
2. LIMNOBIUM L. C. Rich. Fresh-water herbs. Leaves with dilated
blades terminating petioles. Flowers monoecious. Fruit smooth. Three or
four species, American.
1. L. Spongia (Bose.) L. C. Rich. Leaves
several together; blade ovate to suborbi-
cular or reniform, 2-5 cm. broad: fruit
glabrous, nodding.-(FROG 'S-BIT.)-Shallow
water and mud, various provinces, Fla. to
Tex., Mo., Ont., and N. J.-Sum.-fall.--The
plants are very variable in size, and the
leaves vary in shape and have short or long
petioles. In marshes as the water dries up,
the frog 's-bit grows rapidly and often
covers acres of these low lands with a bright
ORDER POALES- POAL ORDER
Mostly perennial caulescent or acaulescent plants, known as grasses
and sedges. Stems sometimes conspicuously jointed. Leaves alternate,
mostly sheathing at the base: blades usually narrow and elongate, entire or
nearly so. Flowers variously disposed in a simple or compound inflores-
cence, perfect or rarely monoecious or dioecious, incomplete, inconspicu-
ous, borne in the axils of chaffy bracts or scales glumess). Fruit a cary-
opsis (grain) or an achene, or rarely a nut, or baccate.
Leaves 2-ranked, their sheath-margins usually not united: stein mostly hollow: fruit
a grain caryopsiss). Fam. 1. POACEAE.
Leaves 3-ranked, their sheath-margins united: stem solid:
fruit an achene. Fam. 2. CYPERACEAE.
FAMILY 1. POACEAE GRASS FAMILY1
Herbs or rarely woody plants, with often hollow stems culmss)
closed at the nodes, and 2-ranked parallel-veined leaves, these consisting of
2 parts, a lower (the sheath), enveloping the culm, its margins overlapping
or sometimes grown together, an upper (the blade), usually flat, while be-
tween the two on the inside, a membranaceous hyaline or hairy appendage
(the ligule). Flowers perfect (rarely unisexual), small, with no distinct
perianth, arranged in spikelets consisting of a shortened axis (rachilla)
and 2 to many 2-ranked bracts, the lowest 2 being empty (the glumes,
rarely 1 or both of these obsolete), the 1 or more succeeding ones lemmass)
bearing in their axils a single flower, and, between the flower and the
rachilla, a second 2-nerved bract (the palea). Stamens 1 to 6, usually 3,
with very delicate filaments and 2-celled anthers. Pistil 1, with a 1-celled
1-ovuled ovary, 2 (rarely 1 or 3) styles, and usually plumose stigmas.
Fruit a caryopsis (grain) with starchy endosperm and a small embryo at
the base on the side opposite the hilum.-The perianth is usually repre-
sented by 2 (rarely 3) small hyaline scales (the lodicules) at the base of
the flower inside the lemma and palea. The lemma, palea, and inclosed
flower constitute the floret. The spikelets are almost always aggregated
in an inflorescence at the ends of the main stems or branches. The grain
or caryopsis (the single seed and the adherent pericarp) may be free, as
in wheat, or permanently inclosed in the lemma and palea as in the oat.
Rarely the seed is free from the pericarp, as in species of Sporobolus and
Eleusine. The stems of bamboos are woody as are also those of a few
genera, such as Olyra and Lasiacis, belonging to other tribes. The culms
are solid in our species of the tribes Tripsaceae and Andropogoneae. The
margins of the sheaths are grown together in species of Bromus, Festuca,
Melica, Panicularia, and others. The parts of the spikelet may be modified
in various ways. The first, and more rarely also the second, glume may be
wanting. The lemmas may contain no flower, or even no palea, or may be
reduced or rudimentary. The palea is rarely wanting in perfect florets as
in species of Agrostis.-Comprises about 500 genera and 7,000 species very
widely distributed in latitude, altitude, and habitat. The so-called cereals
are of great economic importance.
Spikelets with 1 perfect terminal floret (disregarding those of the staminate and
neuter spikelets) and a sterile or staminate floret below, usually represented by
a sterile lemma only, one glume sometimes, both glumes rarely, wanting: articu-
lation below the spikelets either in the pedicel, in the rachis, or at the base
of a cluster of spikelets, the spikelets falling entire, singly, in groups, or together
with joints of the rachis: spikelets, or at least the fruits, more or less dorsally
compressed (except in some genera of Nazieae). (SUBFAMILY PANICATAE.)
Glumes indurate: fertile lemma and palea hyaline or membranaceous, the sterile
lemma (when present) like the fertile one in texture.
Spikelets unisexual, the pistillate below, the staminate above, on the same in-
florescence, or in separate inflorescences. Tribe I. TRIPSACEAE.
Spikelets perfect, staminate or neuter ones some-
times also present.
Spikelets in pairs; one sessile and perfect,
the other pedicelled and usually stami-
nate or neutral (the pedicellate one some-
times obsolete, or rarely both pedicellate) :
lemmas hyaline. Tribe II. ANDROPOGONEAE.
SContributed by Albert Spear Hitchcock.
Spikelets in groups of 2-5, the groups fall-
ing entire from the continuous axis: lem-
Glumes membranaceous: fertile lemma and palea
indurate, at least firmer than the glumes: sterile
lemma like the glumes in texture.
Spikelets. 1- to many-flowered, the reduced florets, if
any, above the perfect florets (except in Phala-
rideae: sterile lemmas below as well as above in
Campulosus and Uniola) : articulation usually
above the glumes: spikelets usually more or less
laterally compressed. (SUBFAMILY POATAE.)
Plants woody, the stem perennial: spikelets sev-
Plants herbaceous, the stem annual.
Spikelets with 2 staminate, neuter or rudimen-
tary lemmas unlike and below the fertile
lemma: no sterile or rudimentary florets
Spikelets without sterile lemmas below the per-
fect floret (or these rarely present and
like the fertile ones.)
Spikelets unisexual, articulate below the
glumes, 1-flowered, terete or nearly so.
Spikelets perfect (rarely unisexual but then
not as above), usually articulate above
Spikelets articulate below the glumes, 1-
flowered, very flat, the lemma and
palea about equal, both keeled; glumes
small or wanting.
Spikelets articulate above the glumes
(rarely below, but the glumes, at
least one, then well developed).
Spikelets sessile on a usually continu-
ous rachis (short-pedicellate in
Leptochloa: the rachis disar-
ticulating in Hordeum) : articu-
lation above the glumes except
Spikelets on opposite sides of the
rachis: spike terminal, single.
Spikelets on one side of the ra-
chis: spikes usually more than
1, digitate or racemose.
Spikelets pedicellate in open or con-
tracted, sometimes spike-like,
Spikelets 2- to many-flowered.
Glumes as long as the lowest
floret, usually as long as the
spikelet : lemmas awned
from the back awnlesss in
Koeleria and Sphenopholis).
Glumes shorter than the first
floret: lemmas awnless or
awned from the tip or from
a lifid apex.
Tribe I. TRIPSACEAE
Tribe III. NAZIEAE.
Tribe IV. PANICEAE.
Tribe XIII. BAMBUSEAE.
Tribe VII. PHALARIDEAE.
Tribe VI. ZIZANIEAE.
Tribe XII. HORDEAE.
Tribe X. CHLORIDEAE.
Tribe VIII. AGROSTIDEAE.
Tribe IX. AVENEAE.
Tribe XI. FESTUCEAE.
Fruiting spikelets not enclosed in a hard bead-like involucre.
Staminate and pistillate spikelets in the same inflorescence, the former comprising
the upper part of the spike and the latter the lower. 1. TRIPSACUM.
Staminate and pistillate spikelets in separate inflores-
cences, the former in racemes borne in terminal
panicles, the latter in spikes subtended by and
enclosed by large bracts.
Pistillate spikes separate, the rachis articulate:
fruits enclosed. 2. EUCHLAENA.
Pistillate spikes united into a thick receptacle-like
axis (cob) : fruits exposed. 3. ZEA.
Fruiting spikelets enclosed in a hard bead-like involucre
formed from the indurate sheath of the subtending
bract. 4. CoIx.
Tribe II. ANDROPOGONEAE
Spikelets all perfect, surrounded by copious soft hairs.
Rachis continuous, the spikelets falling: spikelets of
the pair unequally pedicellate.
Racemes in a narrow splike-like panicle: spikelets
Racemes in an open, usually flabellate, panicle:
Rachis breaking up into joints at maturity with the
spikelets attached: one spikelet sessile, the other
Spikelets unlike, the sessile perfect, the pedicellate sterile.
Pedicel thickened, appressed to the thickened rachis-
joint (at least parallel to it) or adnate to it:
spikelets awnless, appressed to the joint.
Rachis-joint and pedicel adnate, forming a short
flat joint, this sunken in the open side of the
globose first glume of the sessile spikelet:
sterile spikelet conspicuous.
Rachis-joint and pedicel distinct, the sessile spike-
let appressed to them, its first glume lanceo-
Racemes subcylindric: rachis-joints and pedicels
glabrous, much thicker at the summit, the
spikelets sunken in the hollow below: sterile
Racemes flat: rachis-joints and pedicels woolly,
not much thicker at the summit: sterile spike-
let staminate or neuter.
Pedicel not thickened (if slightly so the spikelets
awned), neither appressed nor adnate to the
rachis-joint, this usually slender: spikelets usu-
Fertile spikelet with a hairy-pointed callus, formed
of the attached supporting rachis-joint or
pedicel: awns strong.
Racemes reduced to a single joint, long-pedun-
cled, in a simple open panicle.
Racemes of several to many joints, single.
Fertile spikelet without a callus, the rachis dis-
articulating immediately below the spikelet:
awns slender, sometimes wanting.
Racemes of several to many joints, solitary, digi-
tate, or aggregate.
Racemes reduced to 1 or few joints: these mostly
peduncled in a subsimple or compound
Pedicellate spikelets staminate.
Pedicellate spikelets wanting, the pedicel only
Tribe III. NAZIEAE
Aunuals with flat leaf-blades and spikes of bur-like spike-
Tribe IV. PANICEAE
Spikelets monoecious: leaf-blades petioled.
eSpikelets all perfect.
Spikelets of 2 kinds, aerial and subterranean.
%Spikelets all of one kind.
Spikelets sunken in the cavities of the flattened
Spikelets not sunken in the rachis.
Spikelets subtended or surrounded by 1 to many
bristles, these distinct or more or less con-
nate, forming an involucre.
Bristles persistent, the spikelets deciduous.
Bristles falling with the spikelets at ma-
Bristles not united at base, slender, often
Bristles united into a bur-like involucre,
the bristles retrorsely barbed.
Spikelets not subtended by bristles.
Glumes or sterile lemma awned. (Awn short,
concealed in the silky hairs of the
spikelet in Tricholaena: awn reduced to
a point in Echinochloa colonum.)
Inflorescence paniculate: spikelets silky. 32. TRICHOLAE
Inflorescence of unilateral simple or some-
what compound racemes along a
common axis: spikelets smooth or
hispid, not silky.
Leaf-blades lanceolate, broad and thin:
glumes 2-lobed, awned from between
the lobes. 30. OPLISMENi
Leaf-blades long and narrow: glumes
awned from the tip. 31. ECHINOCH
Glumes and sterile lemma awnless.
Fruit cartilaginous-indurate, flexible, usu-
ally dark-colored, the lemma with
more or less prominent white hya-
line margins, these not inrolled.
Spikelets in racemes, covered with long
silky hairs, the racemes panicled. 19. VALOTA.
Spikelets glabrous or variously pubes-
cent, but not long-silky.
Spikelets in slender racemes more
or less digitate. 20. SYNTHERIS
Spikelets in panicles.
Fertile lemma boat-shaped:
panicles narrow. 18. ANTHAENA
Fertile lemma convex: panicles
diffuse. 21. LEPTOLOMI
Fruit chartaceous-indurate, rigid.
Spikelets placed with the back of the
fruit turned away from the
rachis of the racemes, usually
single (not in pairs).
First glume and the rachilla-joint
forming a swollen ring-like
callus below the spikelet. 22. ERIOCHLOA
First glume present or wanting,
not forming a ring-like callus
below the spikelet.
First glume present: racemes
racemose along the main axis. 23. BRACHIARI
First glume wanting: racemes
digitate or subdigitate. 24. AXONOPUS.
SSpikelets placed with the back of the
fruit turned toward the rachis of
the spike-like racemes, or pedi-
cellate in panicles.
Fruit long-acuminate: both glumes
wanting. 25. REIMAROCI
Fruit not long-acuminate: at least
one glume present.
First glume typically wanting:
sub-sessile in spike-like
racemes. 26. PASPALUM,
First glume present: spikelets
usually in panicles.
Second glume inflated-sac-
cate, this and the sterile
lemma much exceeding the
stipitate fruit. 29. SACCIOLEPr
Second glume not inflated-
Stems woody: plants
bamboo-like: fruit with
a tuft of down at the
apex. 28. LASIACIS.
Stems herbaceous: no
tuft of down at the
apex of the fruit. 27. PANICUM.
Tribe V. ORYZEAE
Glumes minute: lemma often awned. 39. bRYZA.
Glumes wanting: lemma awnless. 40. HOMALOCE
Tribe VI. ZIZANIEAE
Stem slender, low: staminate and pistillate spikelets borne
in separate inflorescences.
Inflorescence a few-flowered spike: plants not stolonif-
Inflorescence a panicle: plants stoloniferous.
Stem robust, tall: staminate and pistillate spikelets borne
in the same panicle.
Spikelets in pairs, the larger one sessile and pistillate,
the smaller staminate and pedicellate.
Spikelets not paired.
Plant annual: pistillate spikelets on the ascending
upper branches, the staminate on the spreading
lower branches of the panicle.
Plant perennial: pistillate spikelets at the ends, the
staminate below on the same branches of the
Tribe VII. PHALARIDEAE
Sterile florets reduced to small awnless scale-like lemmas:
spikelets much compressed laterally.
Sterile florets consisting of awned hairy empty lemmas
exceeding the fertile floret: spikelets terete.
Tribe VIII. AGROSTIDEAE
Rachilla articulate below the glumes, these falling with
Rachilla not prolonged behind the palea: panicle
dense and spike-like: glumes united toward
the base, ciliate on the keel.
Rachilla prolonged behind the palea: panicle nar-
row or open, not dense: glumes not united,
not ciliate on the keel.
Panicle narrow; lemma with a slender bent
twisted awn from the bifid apex.
Panicle open and drooping: lemma with a minute
straight awn just below the entire apex.
Rachilla articulate above the glumes.
Fruit indurate, terete, awned, the nerves obscure: cal-
lus well-developed, oblique, bearded.
Awn trifid, the lateral divisions sometimes short,
rarely obsolete (when obsolete no line of demar-
cation between awn and lemma as in the next).
Awn simple, a line of demarcation between the awn
and the lemma.
Fruit thin, or firm, but scarcely indurate, if firm the
nerves prominent or evident: callus not well-
Glumes longer than the lemma.
Glumes compressed-carinate, abruptly mucronate,
stiffly ciliate on the keels: panicle dense,
cylindric or ellipsoid.
Glumes not compressed-carinate, not ciliate.
Florets bearing a tuft of hairs at the base
from the short callus, the hairs at least
half as long as the lemma.
Florets without hairs at the base or the
hairs very short.
Glumes not longer than the lemma, usually shorter
(the awn-tips longer in Muhlenbergia race-
Lemma awned from the tip or mucronate, 3-5-
Rachilla prolonged behind the palea: floret
Rachilla not prolonged: floret not stipitate.
Lemma awnless or awned from the back.
Callus bearded: lemma and palea chartace-
Panicles spike-like: rachilla prolonged.
Panicles open: rachilla not prolonged.
Callus not bearded.
Tribe IX. AVENEAE
Spikelets falling entire: first glume much smaller than the
Florets alike, perfect. 66. SPHENOPH
Florets unlike, the lower perfect, awnless, the upper
staminate and bearing a hooked awn. 62. NOTHOLCU
Spikelets not falling entire, the glume persistent.
Florets 2, the lower staminate, awned; the upper per-
fect, awnless. 69. ARRHENAT:
Florets 2 or more, all alike except the reduced upper
Awn arising from between the teeth of a bifid apex,
flattened, twisted. 70. DANTHONI
Awn dorsal, not flattened: lemma often bifid at
Spikelets large, the glumes over 1.5 cm. long. 68. AVENA.
Spikelets less than 1 cm. long.
Lemmas keeled: awn arising from above the
Lemmas bidentate: perennial. 65. TRISETUM.
Lemmas entire: annual. 67. KbELERIA.
Lemmas convex: awn from below the middle.
Rachilla prolonged behind the upper
floret: lemmas truncate and erose-
dentate. 63. AIRA.
Rachilla not prolonged: lemmas tapering
into 2 slender teeth. 64. ASPRIS.
Tribe X. CHLORIDEAE
Spikelets with more than 1 perfect floret.
Spikes numerous, slender, racemose on an elongate axis. 79. LEPTOCHLO
Spikes few, digitate or nearly so.
Rachis of spike extending beyond the spikelets. 78. DACTYLOCT
Rachis not prolonged. 77. ELEUSINE.
Spikelets with only 1 perfect floret, often with additional
imperfect florets above.
Spikelets without additional modified florets, the
rachilla sometimes prolonged.
Rachilla articulate below the glumes, the spikelets
falling entire. 72. SPARTINA.
Rachilla articulate above the glumes.
Spikes digitate: rachilla prolonged. 71. CAPRIOLA.
Spikes racemose along the main axis: rachilla
Spikelets with one or more modified florets above the
Spikelets with 2 sterile florets below the perfect
one: second glume bearing a squarrose spine
on the back : spike single, recurved. 73. CAMPULOSI
Spikelets with no sterile florets below the perfect
one: second glume without a squarrose spine:
spikes usually several.
Spikes digitate or nearly so. 74. CHLORIS.
Spikes racemose along the main axis.
Spikelets distant, appressed: spikes slender,
elongate. 75. GYMNOPOG(
Spikelets contiguous or crowded, not ap-
pressed: spikes usually short, relatively
stout. 76. BOUTELOUA
Tribe XI. FESTUCEAE
Tall stout reeds with large plume-like panicles: lemmas
or rachilla with long silky hairs as long as the
Lemmas hairy: rachilla naked.
Lemmas naked: rachilla hairy.
Low or rather tall stems, rarely over 1.5 m. tall.
Plant dioecious, perennial: lemmas glabrous: grasses
of salt or alkaline soil.
Plant low and creeping: spikelets obscure, scarcely
differentiated from the short crowded rigid leaves.
Plant erect from creeping rootstocks: spikelets in
a narrow simple exserted panicle.
Plant not dioecious (except in a few species of Poa
with villous lemmas and in an annual species of
Lemmas 3-nerved, the nerves prominent, often hairy.
Lemrhas pubescent on the nerves or callus: mid-
nerve usually exserted as an awn or mucro.
Palea long-ciliate on the upper half.
Palea sometimes villous, but not long-ciliate
on the upper half.
Lemmas not pubescent on the nerves or callus
(the internerves sometimes sparsely pubes-
Lemmas chartaceous : grain large and
beaked, at maturity forcing the lemma and
Lemmas membranaceous, if firm the grain
neither large nor beaked.
Lemmas 5- to many-nerved, the nerves sometimes
Spikelets with 1 to 4 empty lemmas below the
fertile florets: nerves obscure: lemmas
Spikelets with no empty lemmas below the fer-
tile florets : nerves usually prominent:
lemmas membranaceous (firm in a few
species of Bromus and Festuca).
Lemmas keeled on the back.
Spikelets strongly coinpressed, crowded in
1-sided clusters at the ends of the stiff
Spikelets not strongly compressed, not
crowded in 1-sided clusters.
Lemmas awned from a minutely bifid
apex awnlesss or nearly so in B.
unioloides) : spikelets large.
Lemmas awnless: spikelets small.
Lemmas rounded on the back (slightly keeled
toward the summit in Festuca and
Glumes papery: lemmas firm, strongly
nerved, scarious-margined : upper
florets sterile, often reduced to a
club-shaped rudiment enfolded by
the broad upper lemmas: spikelets
tawny or purplish.
Glumes not papery: upper florets not un-
like the others.
Nerves of the lemma prominent, paral-
lel, not converging at the sum-
mit or but slightly so: lemmas
awnless, mostly obtuse.
Nerves of the lemma converging at the
summit: lemmas awned or
Florets minute: spikelets many-
flowered, in small rigid pani-
Florets 4 mm. or more long: spike-
lets few to several flowered,
not in rigid panicles.
Lemmas entire, awned from the
tip or pointed.
Lemmas awned or awn-tipped
from a minutely bifid apex.
Tribe XII. HORDEAE
Spikelets solitary at each node of the rachis.
Spikelets placed edgewise to the rachis: glume 1 except
in the terminal spikelet.
Spikelets placed flatwise to the rachis.
Spikelets more than 1 at each node of the rachis.
Spikelets 3 at each node of the rachis, 1-flowered, the
lateral pair pedicelled, usually reduced to awns.
Spikelets 2 at each node of the rachis, 2- to 6-flowered,
Glumes usually equalling the florets: spikelets ap-
pressed or ascending.
Glumes wanting or reduced to 2 short bristles:
spikelets horizontally spreading at maturity:
spikes very loose.
95. BROM S.
Tribe XIII. BAMBUSEAE
Gregarious woody grasses with usually branching stems. 101. ARUNDINARIA.
1. TRIPSACUM L. Robust perennials, with monoecious terminal and
axillary inflorescences, of 1, 2, or 3 spikes, the pistillate below, breaking up
into bony seed-like joints, the staminate above on the same rachis, deciduous
as a whole. Staminate spikelets 2-flowered, in pairs on a continuous rachis,
one sessile, the other sessile or pedicellate. Pistillate spikelets single at each
joint of the thick, hard, articulate lower part of the same rachis, sunken in
hollows in the joints, consisting of one perfect floret and a sterile lemma;
first glume coriaceous, nearly enfolding the spikelet, fitting into and closing
the hollow of the rachis: second glume similar to the first but smaller, enfold-
ing the remainder of the spikelet: sterile and fertile lemmas and palea hya-
line.-About 7 species in temperate and tropical America.-GAMA-GRASSES.
Leaf-blades 1-2 cm. wide, flat: plant 1-2 m. tall. 1. T. dactyloides.
Leaf-blades 1-3 mm. wide, more or less involute: plant less than
1 m. tall. 2. T. floridanum.
1. T. dactyloides L. Plant commonly 2-4 m. tall: leaf-blades more or less
auricled at the base: rachis of the pistillate spike 5-6 mm. in diameter:
terminal spikes usually 2-3 together, the
contiguous sides flattened, those from the
axils usually single, cylindric, the long pur-
ple stigmas showy during anthesis.-Moist
soil, riverbanks, pond-margins, and ham-
mocks, various provinces, Fla. to E Tex.,
Nebr., and R. I.-(W. I., Mex., S. A.)-
Sum.-fall, or all year S.--Used for forage /
2. T. floridanum Porter. Smaller than T.
dactyloides in all ways, commonly less than
1 m. tall: leaf-blades not auricled at the
base: rachis of the pistillate spike 3-4 mm.;
in diameter.-Low rocky pinelands, Ever-
glade Keys, and adj. Everglades, pen. Fla.and Florida Keys.-All year.
2. EUCHLAENA Schrad. Tall monoecious annuals or perennials, with
broad leaf-blades and long sheaths. Staminate spikelets 2-flowered, in pairs,
unequally pedicellate, on a simple rachis: racemes several, in a terminal corym-
biform panicle. Pistillate spikelets single
on opposite sides and sunken in cavities in ,'
the hardened joints of an obliquely articu- -
late rachis, the indurate first glume covering
the cavity, the spikes 2-several together, en-
closed in the leaf-sheaths.-Three species,
natives of Mex.
1. E. mexicana Schrad. Stem up to 5 m.
tall: leaf-blades elongate-lanceolate, 1 m. j
long or less, up to 8 cm. wide: staminate
racemes mostly 10-15 cm. long, the spike-
lets about 8 mm. long: pistillate enclosed
in trapezoid joints: spikelets about 7 mm.
long.-(TEOSINTE.)---Waste places and cultivated grounds, Fla. Nat. of Mex.
-Sum.-fall.-Plants rarely flower, and mature fruits only in S Fla. Grown
for forage and for soil improvement.
3. ZEA L. A tall annual grass, with broad, conspicuously distichous
blades, monoecious inflorescences, staminate flowers in spike-like racemes, these
numerous, forming large spreading panicles (tassels) terminating the stems.
Pistillate inflorescence in the axils of the leaves, the spikelets in 8 to 16 or
even as many as 30 rows on a thickened, almost woody axis (cob), the whole
enclosed in numerous large foliaceous bracts (husks), the long styles (silk)
protruding from the tops as a silky mass of threads. Spikelets unisexual;
staminate spikelets 2-flowered, in pairs, on one side of a continuous rachis,
one nearly sessile, the other pedicellate: glumes membranaceous, acute: lemma
and palea hyaline: pistillate spikelets sessile, in pairs, consisting of one fertile
floret and one sterile floret, the latter sometimes developed as a second fertile
floret: glumes broad, rounded or emarginate at apex: style very long and
slender, stigmatic along both sides well toward the base.-Consists of the
following species, known only in cultivation or as an escape, and in many
1. Z. Mays L. Stem up to 4 m. tall, stout,
leafy: leaf-blades linear-lanceolate, elongate,
fully 10 cm. wide, or less: staminate
panicle erect, 20-30 cm. long, with spread-
ing or drooping branches: pistillate panicle
ultimately protruding from the leaf-sheaths,
the grains white or variously colored.-
(CORN. INDIAN-CORN. MAIZE.)--Roadsides,
fields, and waste-places, locally throughout
our range. Nat. of tr.op. Am.-Sum.-
fall.-Extensively cultivated in many vari-
eties in America from prehistoric times. t '
Corn is one of the important economic
plants of the world.
4. COIX L. Diffuse monoecious annuals, with narrow elongate leaf-
blades. Inflorescence compound, each branch bearing a bead-like involucre
enclosing 1 pistillate and 2 sterile spikelets, and a short staminate raceme
on a slender peduncle protruding from an orifice at the summit of the in-
volucre. Grain enclosed in the hard bead-
like involucre.-Four species, natives of
Asia; the following now widely distributed
in the tropics.
1. C. Lachryma-Jobi L. Stem 0.5-1.5 m. "
tall, much-branched: leaf-blades elongate,
linear-lanceolate, 4 cm. wide or less: spike-
lets and spikes terminating fascicles of
branches from the leaf-axils: involucres .
globular or ovoid, mostly about 1 cm.
long, white or bluish, shining.-(TEAR- :1
GRASS. JOB'S-TEARS. CHRIST 'S-TEARS.)-
Widely cult. and locally escaped, cult. \.,
grounds and roadsides, Coastal Plain, Fla.
to Tex. Nat. of E Ind.-(IW. I., Mex.,
C. A., S. A.)-Spr.-fall.-Employed medicinally, while the hard mature in-
volucres are used as beads.
5. IMPERATA Cyr. Slender erect perennials with terminal narrow
woolly panicles. Spikelets all alike, awnless, in pairs, unequally pedicellate
on a slender continuous rachis, surrounded by long silky hairs: glumes about
equal, membranaceous: sterile lemma, fertile lemma, and palea thin and
hyaline.-Five species, in nearly all tropical
and subtropical regions.
1. I. brasiliensis Trin. Stem 0.5-1 m. tall,
from scaly rootstocks: leaf-blades mostly
basal, 3-8 mm. wide, the stem-blades short,
the uppermost leaf reduced to a nearly
bladeless sheath: panicle pale, usually not ".'
over 10 cm. long.-(BRAZILIAN BLADY-GRASS.\ /
SILVER-PLUME.)--Pinelands, prairies, sand-
dunes and Everglades, S pen. Fla.-(W. I.,
Mex., C. A., S. A.)-All year.-Conspicuous
on account of the erect narrow silvery .
plume-like inflorescence. The plants are
often tufted. '
6. MISCANTHUS Anderss. Robust perennials with usually flat leaf-
blades and terminal panicles of aggregate slender racemes. Spikelets all per-
fect, in pairs, unequally pedicellate along a continuous rachis: glumes mem-
branous: lemma hyaline, 2-toothed, with a
slender, somewhat geniculate and flexuous
awn.-Six species, natives of Asia.
1. M. sinensis Anderss. Stems 1-2 m. tall:
leaf-blades 80 cm. long or less, 1-1.5 cm.
wide: panicle 20-40 cm. long, flabellate: /
spikelets 4.5-5 mm. long, yellowish-brown, / /
shining, encircled at the base with white or
purplish hairs equalling or exceeding the \
spikelet, the awns 8-10 mm. long, twisted
at the base.-(EULALIA.)-Waste-places and
roadsides, various provinces, Fla. to Miss.
and Mass. Escaped from cult. Nat. of E
Asia.-Spr.-fall.-Frequently cultivated for
ornament. Sometimes with variegated leaves.
7. SACCHARUM L. Tall perennials with many-jointed stems, flat leaf-
blades, and usually large loose silky terminal panicles. Spikelets in pairs,
one sessile, the other pedicellate, both per-
fect, awnless, in slender racemes, the rachis /
disarticulating. Glumes acute, membranous,
or indurate at base: lemmas hyaline, the \
fertile sometimes wanting.-Twelve species,
most abundant in the tropical regions of the
1. S. officinarum L. Stem tall and leafy,
sometimes several meters high, usually de- 4
cumbent and rooting at the base: leaf-- "
blades often over 1 m. long, 6 cm. wide or
less: panicle plume-like, mostly 60 cm. long
or more, loose.-(SuGAR-CANE.)-Old fields
and cult. grounds, Coastal Plain, Gulf States. Often persisting after cult. Nat.
of trop. Asia.-Spr.-fall.-Cultivated in many varieties as sugar-cane, the main
source of sugar. Sometimes used for forage. Matures its fruit in Fla.
8. ERIANTHUS Michx. Reed-like perennials, with flat leaf-blades and
terminal oblong usually dense silky panicles. Spikelets all alike, in pairs along
a slender axis, 1 sessile, the other pedicellate, the rachis disarticulating below
the spikelets, the rachis-joint and pedicel falling attached to the sessile-spike-
let: glumes coriaceous, equal, usually copiously clothed, at least at the base,
with long silky spreading hairs: sterile and fertile lemmas hyaline, the latter
bearing a slender awn: palea small, hyaline.-About 20 species, natives of
nearly all tropical and temperate regions.-WOOLLY BEARD-GRASSES. PLUME-
GRASSES.-Some species are cultivated for ornament, but the plants are too
coarse for forage.
Spikelets with a tuft of hairs at base.
Awn flat, spirally coiled at base, the upper portion more or less bent and flexuous
or loosely spiral.
Basal hairs about as long as the brownish spikelets: panicle not conspicuously
hairy, the main axis and branches visible: stems usu-
ally glabrous below panicle. 1. E. contortus.
Basal hairs copious, about twice as long as the yellowish
spikelets : panicle conspicuously woolly, the hairs hiding
the main axis and branches : stems villous below panicle. 2. E. divaricatus.
Awn terete, or at base flattened, not coiled, the upper portion
usually straight, sometimes flexuous.
Basal hairs rather sparse, shorter than the spikelet. 3. E. brevibarbis.
Basal hairs copious, longer than the spikelet. 4. E. saccharoides.
Spikelets naked, or nearly so, at base. 5. E. strictus.
1. E. contortus Ell. Stem 1-2 m. tall, glabrous or sometimes sparsely ap-
pressed-pilose below the panicle, the nodes glabrous or pubescent with erect
deciduous hairs: panicle 15-30 cm. long,
narrow, the branches ascending but not 4 Nl -/ -
closely appressed: spikelets 6-8 mm. long, /\,, -
brownish, glabrous on the back, the rachis- '
joints and pedicels villous, the awn about
2 cm. long. [E. Smallii Nash]-Moist L'
pinelands, thickets, and dry slopes, Coastal -'- \
Plain, Fla. to E Tex., Okla., and Md.
2. E. divaricatus (L.) A. Hitchc. Stem
1.5-3 m. tall, appressed-villous below the
panicle, the nodes usually appressed-hirsute:
panicle 20-30 cm. long, tawny or purplish: iJ
spikelets 5-6 mm. long, pale, sparsely vil- ,----- /
lous, shorter than the copious basal hairs, ---
the awns 1-1.5 cm. long. [E. alopecuroides
Ell.]-Damp woods, thickets, rocky hills, and borders of fields, Coastal Plain
and occasionally more northern provinces, Fla. to E Tex. and S N. J.
3. E. brevibarbis Michx. Stem 1-2 m. tall, glabrous, the nodes glabrous or
appressed-hirsute: panicle 20-30 cm. long, brown or purplish, the branches
ascending, not conspicuously woolly: spikelets 6-7 mm. long, brown.-Moist
soil, low thickets and about ponds, Coastal Plain, Fla. to La. and Del.
4. E. saccharoides Michx. Stem 1-3 m. tall, appressed-villous below the
panicle, the nodes hispid with appressed-deciduous hairs: panicle oblong or
ovoid, tawny or purplish, 10-40 cm. long, rather compact (E. compacts) or
somewhat open: spikelets 5-7 mm. long, sparsely long-villous on the upper
part. [E. laxus Nash E. compacts Nash E. Tracyi Nash]-Moist soil,
swamps, wet hammocks, and marshes, Coastal Plain, Fla. to E Tex. and
N. J.--(W. I.)
5. E. strictus Baldw. Stem 1-2 m. tall, glabrous, the nodes hirsute with stiff
erect deciduous hairs: panicle 20-40 cm. long, strict, the branches closely ap-
pressed: spikelets about 8 mm. long, scabrous, the awn straight, about 1.5 cm.
long.-Moist soil, marshes, low. thickets and beds of streams, Coastal Plain and
rarely adj. provinces, Fla. to Tex., S Mo., Tenn., and S. C.
9. MANISURIS L. Slender rather tall perennials or annuals with usually
numerous smooth cylindric or flattened spikes or racemes, single on the stem and
branches. Spikelets awnless in pairs at the nodes of a thickened articulate
rachis, one sessile and fertile, the other pedicellate and sterile, the pedicel thick-
ened and appressed to the rachis, the sessile spikelet fitting closely against the
rachis, forming a cylindric or subcylindric raceme: glumes obtuse, the first
coriaceous, fitting over the hollow containing the spikelet, the second less
coriaceous than the first; sterile and fertile lemmas and palea hyaline: pedicel-
late spikelet reduced, often rudimentary. [B ttboellia L. f.]-About 20 species,
natives of the warm temperate and tropical regions of both hemispheres. Of
little economic importance.
Leaf-sheath not compressed-keeled: first glume more or less
pitted. 1. M. campestris
Leaf-sheath compressed-keeled: first glume tessellated or
wrinkled, rarely smooth.
First glume tessellated, the depressions rectangular. 2. M. tessellata.
First glume wrinkled, tubercled, or smooth.
Glume bearing prominent transverse wrinkles. 3. M. rugosa.
Glume bearing a few low tubercles or smooth. 4. M. tuberculosa.
Plant annual. 5. M. exaltata.
1. M. campestris (Nutt.) A. Hitchc. Stem 0.3-1 tall, erect, rather slender,
producing short rootstocks: leaf-blades 1-2 mm. wide: raceme 5-15 cm. long,
slightly curved: first glume 4-5 mm. long,
pitted along the obscure nerves. [R. cam-
pestris Nutt B. cylindrica Chapm. M. cylin-
drica Kuntze]-Pinelands and prairies,
Coastal Plain, Fla. to E Tex., S Mo., and
2. M. tessellata (Steud.) Scribn. Stem
0.8-1.2 m. tall, rather stout: raceme 5-12 r
cm. long: spikelets about 4 mm. long. [B. I
corrugata Chapm.]-Moist pinelands, Coastal rF
Plain, Fla. to La. and Ala. f F
3. M. rugosa (Nutt.) Kuntze. Stem 0.7-1.2 f
m. tall: raceme 5-8 cm. long: first glume
with prominent transverse ridges. [M. Chap-
mani Nash B. rugosa Nutt.]-Wet pinelands,
Coastal Plain, Fla. to E Tex. and S N. J.
4. M. tuberculosa Nash. Similar to M. rugosa; but the first glume with a few
short ridges or low tubercles, these sometimes obscure or wanting, the glume
then smooth and shining.-Lake shores and about ponds, pen. Fla.
5. M. exaltata (L. f.) Kuntze. Stem stout, 1 m. tall or more, branching:
leaf-sheaths hispid; leaf-blades elongate, 1-2.5 cm. wide: racemes numerous,
more or less included at base, dwindling at the summit and bearing abortive
spikelets only: first glume of sessile spikelet smooth.-Moist soil, S Fla. Nat.
of S Asia. (W. I.)
10. RYTILIX Raf. Much branched erect annuals with flat leaf-blades,
the numerous racemes single and more or less enclosed in the sheathing
bract, these somewhat clustered in the axils of the leaves. Spikelets awnless, in
pairs, the rachis-joint and pedicel grown
together, the two clasped between the edges ,
of the globose alveolate first glume of the i
sessile spikelet: pedicellate spikelet con-
spicuous, staminate. [Hacckelochloa Kuntze]
-Consists of the following species only: l, ,
1. R. granularis (L.) Skeels. Stem as '
much as 1 m. tall: leaf-sheaths papillose- -4
hispid: raceme 1-2 cm. long. [Manisuris '
granularis Sw. Hackelochloa granularis
Kuntze]-Pinelands, prairies, and waste
grounds, various provinces, Fla. and Ga. to
Ariz. Nat. of E I.--(W. I., Mex., C. A.,
S. A., 0. W.)-A weed in many countries.
11. ELYONURUS Humb. & Bonpl. Erect moderately tall perennials with
solitary spike-like racemes. Spikelets awnless, in pairs along a somewhat tardily
disarticulating rachis, the joints and pedicels thickened and parallel, the sessile
spikelets appressed to the concave side, the pedicellate spikelet staminate, simi-
lar to the sessile one, the pairs falling with a joint of the rachis: first glume
firm, somewhat coriaceous, with a line of bal-
sam glands on the marginal nerves, the apex /
acute or acuminate, bifid: second glume simi-
lar to the first: sterile and fertile lemmas
hyaline: palea obsolete.-About 15 species, ji
circumtropical.-Important grazing grasses \
in tropical America.
1. E. tripsacoides Humb. & Bonpl. Stem
0.6-1.2 m. tall: leaf-blades flat or involute,
2-4 mm. wide, slightly pilose on the upper
surface below: raceme 7-12 cm. long: sessile
spikelet 6-8 mm. long.-Hammocks, pine-
lands, prairies, and open grassy slopes,
Coastal Plain, Fla. to Tex. and Ga.-(Mex.,C. A., S. A.)
12. ANDROPOGON [Royen] L. Mostly slender perennials (in our range),
with solid sometimes tufted stems, the spikelets arranged in racemes, these
single, in pairs, or in 3's or 4's, the common peduncle usually enclosed by a
spathe-like sheath, these sheaths often numerous, forming a compound inflores-
cence, usually narrow, but sometimes in dense subcorymbose masses. Spikelets
in pairs at each node of an articulate rachis, one sessile and perfect, the other
pedicellate and staminate, neuter or reduced to the pedicel, the rachis and
pedicels of sterile spikelet often villous, sometimes conspicuously so: glumes of
fertile spikelet coriaceous, narrow, the first rounded, flat, or concave on the
back, several-nerved, the median nerve weak or wanting: sterile lemma hyaline:
fertile lemma hyaline, narrow, entire or bifid, usually bearing a bent and twisted
awn: palea hyaline, small or wanting: pedicellate spikelet sometimes staminate
and about as large as the sessile spikelet, sometimes reduced or wanting, only
the pedicel present. [Schizachyrium Nees]-About 150 species widely dis-
tributed in temperate and tropical regions.-BROOM-GRASSES. BEARD-GRASSES.
SAGE-GRASSES. SAND-GRASSES. BUNCH-GRASSES.-Some species are important
Racemes single, from bract-like sheaths.-(Schizachyrium.) I. SCOPARII.
Racemes more than one from the spathe or several in a panicle on a
naked peduncle.-(Andropogon.) II. FURCATI.
Leaf-blade flat or folded, not terete.
First glume of sessile spikelet glabrous.
Internodes of rachis glabrous or ciliate at base and near apex only.
Sessile spikelet 4 mm. long: leaf-blades scarcely
1 mm. wide. 1. A. tener.
Sessile spikelet about 6 mm. long: leaf-blades
mostly 2-4 mm. wide. 2. A. semiberbis.
Internodes of rachis and sterile pedicel villous from
base to apex.
Sessile spikelet about 1 cm. long.
Glume of pedicellate spikelet 1-awned. 3. A. maritimus.
Glume of pedicellate spikelet 3-awned. 4. A. littoralis.
Sessile spikelet 6 mm. long. 5. A. stolonifer.
Rootstock wanting. 6. A. scoparius.
First glume of sessile spikelet villous. 7. A. hirtiflorus.
Leaf-blade slender, terete, the upper surface a mere groove. 8. A. gracilis.
1 Pedicellate spikelet staminate, similar to the sessile spikelet. 9. A. provincial
Pedicellate spikelet reduced to 1 or 2 glumes.
Racemes in pairs, the spathes aggregate in a flabellate
inflorescence. 10. A. glomeratus
Racemes 2-4, the spathes not aggregate (somewhat ag-
gregate in A. capillipes).
Peduncle of the 2 (sometimes 3 or 4) racemes less
than 1 cm. long, (2 cm. in A. Tracyi) enclosed
in the spathe.
Silky hairs of the spike dense, concealing the
rachis and sterile pedicels.
Peduncles in each spathe about 5 mm. long. 11. A. longiberbis
Peduncles in each spathe about 2 cm. long. 11a. A. Tracyi.
Silky hairs of the spike comparatively sparse, not
concealing the rachis and sterile pedicels.
Plant green, more or less pilose on the leaf-
sheaths or blades. 12. A. virginicus.
Plant glabrous, often glaucous.
Ligule truincate, concealed within the
folded blade. 13. A. capillipes.
Ligule acutish, protruding from the folded
blade. 14. A. perangusta
Peduncle of the 2-4 racemes more than 1 cm. long,
often long-exserted from the spathe.
Racemes in pairs, usually not over 15 mm. long:
branches bearing the spathes numerous and
slender. 15. A. brachystac
Racemes more than 15 mm. long.
Sheaths, especially the upper, long and in-
flated, more or less aggregate: rachis very
slender and flexuous, the internodes 2-3
mm. long. 16. A. Elliottii.
Sheaths not conspicuously inflated (or occa-
sionally so in A. campyloracheus).
Rachis conspicuously slender and flexuous,
the internodes 7-10 mm. long. 17. A. campylorac
Rachis not conspicuously slender: racemes
Racemes in 4's : plant stout, the sheaths
usually woolly. 18. A. Mohrii.
Racemes in pairs.
First glume of sessile spikelet 2-
nerved between the keels : hairs
on rachis and sterile pedicels not
concealing spikelets. 19. A. Cabanisii.
First glume of sessile spikelet
nerveless between the keels.
Awn twisted into a column at
base. (see A. Tracyi)
Stamen 1 : spikelets 4-5 mm.
long, with brownish hairs
about as long, not con-
cealing the spikelets: awn
rather short. 20. A. arctatus.
Stamens 3: spikelets 5-7
mm. long, with silvery
white hairs as long or
longer, concealing the
spikelets: awn 15-20 mm.
long. 21. A. ternarius.
Awn not twisted into a column
at base: plant stout, much-
branched: spikelets 3 mm.
long. 22. A. floridanus.
1. A. tener (Nees) Kunth. Stem slender, 0.6-1 m. tall, sometimes reclining
or decumbent: leaf-blades scarcely 1 mm. wide: racemes long-exserted, slender,
glabrous, 2-6 cm. long: first glume of ses-
sile spikelet about 3 mm. long, the awn 7-10
mm. long. [S. tenerumn Nees]-Dry pine-
lands, woods, and prairies, Coastal Plain,
Fla. to La. and Tex.-(WV. I., Mex., C. A.,
2. A. semiberbis (Nees) Kunth. Stem
glabrous, erect, 0.6-1.2 m. tall: leaf-blades
glabrous, 2-4 mm. wide: racemes erect,
5-8 cm. long, the rachis straight, the joints
short-hispid at base with erect hairs: sessile
spikelet about 6 mm. long, acuminate, the
awn 10-15 mm. long: sterile pedicel ciliate
on one margin from below the middle.
[S. semiberbe Nees]-Pinelands, pen. Fla.-(W. I., S. A.)
3. A. maritimus Chapm. Stem decumbent at base, often glaucous, 0.4-0.6 m.
long: leaf-sheaths compressed and keeled: racemes 3-5 cm. long, the rachis
slender and becoming flexuous, the hairs about 5 mm. long: sessile spikelet
8-10 mm. long, glabrous, the awn about 1 cm. long: sterile spikelet staminate,
nearly as large as the fertile. [S. mnaritinmum Nash]-Coastal sands, W Fla.
4. A. littoralis Nash. Resembling A. maritimus: sterile. spikelet a single
glume about 5 mm. long, the 3 nerves extending into cusps or awns, the central
distinct, the lateral usually minute, sometimes wanting. [S. littorale Bickn.
S. triaristatum Nash]-Sand-dunes and beaches, Coastal Plain, Fla. to Tex.,
N. Y., and N. J.
5. A. stolonifer (Nash) A. Hitchc. Stem 0.6-1 m. tall, often glaucous: leaf-
sheaths glabrous: racemes 3-4 cm. long, the rachis slender and flexuous, the
hairs about 3 mm. long: sterile spikelet about 3 mm. long. [S. stoloniferum
Nash]-Pinelands, prairies, hammocks, and scrublands, Coastal Plain, Fla.,
and Ga.-Differs from A. scoparius in having rootstocks. Forms rarely have
6. A. scoparius Michx. Stem 0.5-1.5 m. tall, sometimes glaucous: leaf-sheaths
glabrous or sometimes villous: racemes 3-6 cm. long, the rachis slender and
flexuous: sessile spikelet 6-7 mm. long, scabrous, the awn 8-15 mm. long.
[S. scoparium Nash S. villosissimum Nash S. acuminatum Nash]-(LITTLE
BLUE-STEM. BROOM-SEDGE.)-Pinelands, prairies, open woods, hillsides, and dry
fields, various provinces, Fla. to Ariz., Alb., and N. B.
7. A. hirtiflorus (Nees) Kunth. Stem 0.6-1.2 m. tall, often glaucous: leaf-
blades 2-4 mm. wide, smooth: racemes 6-10 cm. long, the base included in the
somewhat inflated upper sheath, the rachis straight, the joints tapering below:
sessile spikelet about 6 mm. long, the awn geniculate and twisted, about 1 cm.
long: pedicellate spikelet reduced to a glume 2-4 mm. long, the pedicel thick,
villous. [A. oligostachyns Chapm. A. feensis Fourn. S. oligostachyum Nash]-
Pinelands, various provinces, Fla., Ga., and Ariz. (W. I., Mex., S. A.)
8. A. gracilis Spreng. Stem slender, tufted, glabrous, 0.2-0.6 m. tall: racemes
2-4 cm. long, silvery white, long-exserted, the rachis slender, very villous:
sessile spikelet about 5 mm. long, the awn geniculate and twisted, 1-2 cm.
long: pedicellate spikelet reduced to an awned or awnless glume, the pedicel
very villous. [S. gracile Nash]-Rocky pinelands, S Fla.-(W. I.)
9. A. provincialis Lam. Glabrous or more or less villous and often glauc-
ous: stem 1-2 m. tall: racemes 2-4, rarely more, on each peduncle, long-ex-
serted, 5-10 cm. long, the peduncles terminal and axillary: rachis straight, the
joints pilose at base and along one or both margins: sessile spikelet 7-10 mm.
long, the first glume slightly sulcate, scabrous, the awn geniculate and tightly
twisted below, 1-2 cm. long: sterile pedicel sparingly short-villous, the hairs
whitish. [A. furcatus Muhl. A. tennesseensis Scribn.]-(BLUE-STEM.)-Dry
soil, open woods, pinelands, and old fields, various provinces, Fla. to Tex.,
Ariz., and Me.
10. A. glomeratus (Walt.) B. S. P. Glabrous and often glaucous the leaf-
sheaths sometimes villous: stem 0.5-1.5 m. tall: racemes 1-3 cm. long, as long as
or a little longer than the somewhat inflated spathe and protruding from its
side, the common peduncle within the spathe, and the stem just below the
spathe villous, the rachis slender and flexuous, long-villous: sessile spikelet 3-4
mm. long, the awn straight, 1-1.5 cm. long: sterile spikelet reduced to a subu-
late glume or wanting, the pedicel slender, long-villous. [A. macrourus Michx.
A. corymbosus Nash A. tenuispatheus Nash]-Low moist grounds, swamps,
marshes, and wet pinelands, Coastal Plain and occasionally adj. provinces, Fla.
to Tex. and Mass.-(W. I., Mex., C. A.)
11. A. longiberbis Hack. Stem slender, 0.5-1 m. tall: racemes in. pairs, 2-3
cm. long, the spathe 3-5 cm. long, enclosing the base of the racemes: sessile
spikelets about 3 mm. long, the awn slender and straight, 10-15 mm. long.
-Dry pinelands, pen. Fla.-A. Tracyi Nash, differs from A. longiberbis in
the longer peduncles (about 2 cm.) of the racemes in each spathe: leaf-sheaths
glabrous.-Pinewoods, Fla. to La.
12. A. virginicus L. Stem virgate, 0.5-1 m. tall: lower sheaths compressed,
equitant: ligule strongly ciliate: spathes scattered along the upper half or
two-thirds of the plant: racemes 2-4 from each spathe, 2-3 cm. long, the
bases enclosed in the spathe, this usually a little longer than the racemes:
rachis very slender, flexuous: sessile spikelet about 3 mm. long, the awn 1-2
cm. long. [A. tetrastachys Ell. A. vaginatus Ell. A. macrourus viridis
Chapm.]-(BROOM-SEDGE.)-Dry grounds, pinelands, open woods, old fields,
and beach sands, various provinces, Fla. to Tex., Mo., and Mass.; also in S
Calif.-(W. I., Mex.)
13. A. capillipes Nash. Differs from A. virginicus in being glabrous and
glaucous, especially the strongly compressed innovations, in having more
flexuous peduncles and often a more compact inflorescence: ligule entire or
minutely ciliate. [A. glaucopsis Nash]-Moist pinelands, Coastal Plain, Fla.
to Miss. and N. C.
14. A. perangustatus Nash. Plant green or slightly glaucous: stem slender,
0.3-0.6 m. tall: sheaths not equitant: leaf-blades very narrow, the blades of
the innovations tightly folded, almost filiform, the ligule 1-1.5 mm. long, firm,
glabrous. [A. virginicus stenophyllus Hack.]-Wet pinelands, Fla.-The leaf-
blades of the innovations are often solid, the upper surface being obliterated.
15. A. brachystachys Chapm. Stem 1-1.5 m. tall: spathes in a long in-
florescence, not usually inflated, the peduncles of the spathes slender, often
flexuous: racemes in pairs, usually about 1 cm. long, the common peduncle
sometimes exserted from the spathe: sessile spikelet about 3 mm. long, the
awn less than 1 cm. long, sometimes wanting.-Moist pinelands, Fla.
16. A. Elliottii Chapm. Stem 0.3-0.8 m. tall: leaf-sheaths more or less villous,
the upper inflated and aggregate: racemes in pairs, 3-4 cm. long, some of the
pedicels exserted from the appressed spathe and from the sheaths, others more
or less included in the inflated upper sheaths: sessile spikelet 4-5 mm. long,
the awn 10-15 mm. long, geniculate and twisted.-Pinelands, prairies, rocky
hills, open dry grounds, and old fields, Coastal Plain and occasionally adj. prov-
inces, Fla. to E Tex., S Mo., and Pa.-(Mex.)-The inflated ferruginous sheaths
are conspicuous in winter.-A. gracilior (Hack.) Nash is a slender form with
sometimes scarcely inflated upper sheaths. [A. subtenais Nash]-Fla. to Miss.
17. A. campyloracheus Nash. Stem 0.4-0.8 m. tall: racemes mostly in pairs,
sometimes in 3's or 4's, 5-10 cm. long, the terminal peduncle long-exserted:
rachis slender and very flexuous, the internodes much longer than the sessile
spikelet, this 3-4 mm. long, the awn as much as 2 cm. long.-Dry pinelands,
Coastal Plain, Fla. to La.
18. A. Mohrii Hack. Stem stout, 0.8-1.2 m. tall: leaves villous, especially at
summit of sheath: racemes in 4's, 2-4 cm. long, protruding from the side of
inflated spathes and about as long as these: rachis scarcely flexuous: sessile
spikelet 4-5 mm. long, longer than the internodes of the rachis, the awn 1.5-2
cm. long.-Wet pinelands and beach sands, Coastal Plain, Ga. to La. and N. C.
19. A. Cabanisii Hack. Stem stout, 0.6-1 m. tall: racemes 4-7 cm. long,
tawny, rather stout, scattered along the upper part of the plant: sessile spike-
let 6-7 mm. long, the first glume firm, broadly lanceolate, the awn about 1 cm.
long.-Dry pinelands, pen. Fla.
20. A. ar6tatus Chapm. Stem 1-1.5 m. tall: racemes 3-5 cm. long, tawny:
sessile spikelet 4-5 mm. long, the awn 1-1.5 cm. long.-Low pinelands, Fla.
21. A. ternarius Michx. Stem 0.8-1.2 m. tall: racemes 3-5 cm. long, silvery
white, rather stout. [A. argyraeus Schult. A. mississippiensis Scribn. & Ball
A. Scribnerianus Nash]-Dry sandy soil, often in pinelands or open woods,
Coastal Plain and rarely Blue Ridge, Fla. to E Tex., Okla., and Del.
22. A. floridanus Scribn. Stem 1-1.5 m. tall: racemes 2-4 cm. long, slender,
the spathes long-exserted on capillary peduncles, numerous in a large loose
inflorescence. [A. Bakeri Scribn. & Ball]-Low pinelands, pen. Fla.
Arthraxon ciliaris cryptastheris Hack. A weak-stemmed, laxly branching
annual, with ascending flowering branches, bearing thin cordate-lanceolate
blades, the inflorescence of several slender racemes in a cluster, occurs in lawns
and old fields, various provinces from Fla. to Ark. and Penn. Nat. of Asia.
13. HOLCUS L. Tall or moderately tall annuals or perennials, with flat
leaf-blades and terminal panicles. Spikelets in pairs, the pedicellate spikelet
well-developed, usually staminate: racemes reduced to 1-5 joints, these dis-
articulating tardily, the racemes in a large open or contracted panicle.-About
10 species widely distributed in tropical and warm temperate regions.
Plants perennial with stout creeping rootstocks. 1. H. halepensis.
Plants annual. 2. H. Sorghum.
1. H. halepensis L. Stem 0.5-1.5 m. tall, arising from a stout creeping root-
stock: panicle oblong or pyramidal, 15-50 cm. long, the branches sometimes
finally drooping: sessile spikelet 4.5-5.5 mm.
long, plump, more or less pubescent, the
awn, if present, 1-1.5 cm. long, deciduous.
[Sorghum halepense Pers. Andropogon
halepensis Brot.]-(JOHNSON-GRASS. EVER-
and waste-places, various provinces, Fla. to
Tex., Calif., Kans., and Mass. Nat. of
Afr.-(W. I., Mex., C. A., S. A.)-Some-
times a troublesome weed. This and the
following species sometimes produce hydro-
cyanic acid in sufficient abundance to poison
2. H. Sorghum L. Annual with stouter
stems and broader leaf-blades. The culti-
vated sorghum or sorgo sometimes persists in fields and waste-places, locally
throughout our range. Nat. of E. I.-(W. I., Mex., C. A., S. A.)-This grass
has been cultivated from prehistoric times in many varieties for food and
forage-SORGO, KAFIR, MILO, SHALLU, KAOLIANG, DURRA, BROOM-CORN, EGYPTIAN-
CORN, CHICKEN-CORN, JERUSALEM-CORN, FETERITA-and for its sweet juice which
is made into sirup.
14. SORGHASTRUM Nash. Erect rather tall perennials, with narrow fiat
leaf-blades and narrow terminal panicles. Spikelets in pairs, one nearly terete,
sessile and fertile, the other wanting, only the hairy pedicel present: glumes
coriaceous, brown or yellowish, hirsute: sterile and fertile lemmas hyaline, the
latter bearing a well-developed bent and twisted awn: racemes reduced to 1 to
few joints.-About 12 species, natives of tropical and temperate regions.-
Awn usually 15 mm. or less long, once bent: spikelets yellowish: panicle rather
dense. 1. S. nutans.
Awn 20 to 30 mm. long, twice bent, twisted below the second bend.
Spikelets chestnut-brown, the ultimate branchlets villous only
at the very tip : panicle loose, not unilateral. 2. S. Elliottii.
Spikelets yellowish-brown, the upper portion of the ultimate
branchlets with long ascending hairs: panicles rather dense,
distinctly unilateral. 3. S. secundum.
1. S. nutans (L.) Nash. Stem 1-2.5 m. tall:
panicle oblong, yellowish or bronze, 20-50 cm.
long, rather compact, the branchlets not flex-
uous: spikelets 6-8 mm. long, the awn genicu-
late and twisted. [Sorghum avenaceum
Chapm. S. numans A. Gray]-(WOOD-GRASS.) ,
-Dry soil, various provinces, Fla. to Tex.,
Ariz., N. D., and Me.-(Mex.)
2. S. Elliottii (Mohr) Nash. Stem 1-1.5 / j0
m. tall: panicle 15-30 cm. long, loose, the
pedicels flexuous or drooping: spikelets 6-7
mm. long. [S. Linnaeanum Nash]-Dry
soil, woods, slopes, and bluffs, Coastal Plain
and rarely adj. provinces, Fla. to E Tex.,
Tenn., and Md.
3. S. secundum (Ell.) Nash. Stem 1-2 m. tall: panicle 20-40 cm. long: spike-
lets 6-8 mm. long. [Sorghum secundum Chapm.]-Pinelands, Coastal Plain,
Fla. to Tex., and S. C.
15. RHAPHIS Lour. Our species annual, with open panicles, the three
spikelets (reduced racemes) borne at the ends of long slender naked branches.
Spikelets in 3's, one sessile and perfect, the
other two pedicellate and sterile, or sometimes
a pair below, one fertile and one sterile: fer-
tile spikelets terete, the glumes coriaceous:
sterile and fertile lemmas hyaline, the latter
long-awned.-Twenty species, widely distrib- /
uted in tropical regions.
1. R. pauciflora (Chapm.) Nash. Stem 0.5-
1 m. tall: panicle very open, the branches /
2-5 cm. long: spikelets about 8 mm. long, the
peduncle disjointing obliquely leaving a long
sharp densely pubescent callus below: awn
stout, 10-14 cm. long, geniculate, twisted
below. [Sorghum pauciflorum Chapm.]-
Pinelands and old fields, pen. Fla.-(Cuba.)
16. HETEROPOGON Pers. Annuals or perennials, often robust with flat
leaf-blades and solitary terminal racemes: rachis slender, the lower part, bearing
the pairs of staminate spikelets, continuous, the remainder disarticulating ob-
liquely at the base of each joint, the joint forming a sharp-barbed callus below
the fertile spikelet, the pedicellate spikelet readily falling, its pedicel remaining,
obscured in the hairs of the callus. Spikelets in pairs, one sessile, the other
pedicellate, both of the lower few to several pairs staminate or neuter, the re-
mainder of the sessile spikelets perfect, terete, long-awned, the,pedicellate spike-
lets, like the lower, staminate, flat, conspicuous: glumes of the fertile spikelet
equal, coriaceous, the first brown-hirsute, infolding the second: lemmas hyaline,
the fertile one bearing a strong bent and twisted brown awn: palea wanting:
glumes of the staminate spikelet membra-
naceous, the first green, faintly many-nerved,
unsymmetrical, one submarginal keel rather
broadly winged, the other wingless, the mar-
gins inflexed, the second glume narrower, 4
symmetrical.-Six species, most abundant in
the Old World. Our species is annual.
1. H. melanocarpus (Ell.) Benth. Stem 1-
2 m. tall, branched: raceme 3-6 cm. long:
sessile spikelet 5-6 mm. long, the awn 10-15
cm. long: pedicellate spikelet 1.5-2 cm. long,
acuminate, the first glume with a row of oil
glands. [H. acuminatus Trin.]-Fields and
open grounds, Coastal Plain, Fla., Ala., and Ga.; also in Ariz.-(Mex., C. A., S. A.)
17. NAZIA Adans. Low annuals with flat leaf-blades and terminal spikes,
the bur-like clusters of spikelets rather closely arranged along a slender axis.
Spikelets in groups of 2-5, the groups falling entire, the spikelets sessile on a
short zigzag axis, the upper 1-3 reduced and sterile, the lower perfect, 1-flowered:
first glume small and thin, or wanting:
second glume of the two lower spikelets
3-nerved, and with a row of prickles on each
side of each nerve: lemma and palea thin.-
Three species, natives of the tropics, and
more widely naturalized.
1. N. racemosa (L.) Kuntze. Stem usually
branching at the base and decumbent, 30
cm. long or less: leaf-blades ciliate, mostly
less than 5 cm. long: spike 8 cm. long or qi
less: spikelets 4-4.5 mm. long, the acuminate
apex projecting beyond the spines, the clus-
ter pedicelled. (PRICKLE-GRASS.) Waste '
places, especially ballast, coast region of
N. C., and at more northern seaports; also in Tex. and Ariz. Nat. of Eu.
18. ANTHAENANTIA Beauv. Erect perennials, with short creeping
rootstocks, narrow, firm flat leaf-blades, the uppermost much reduced, and nar-
row panicles, the slender branches ascending or appressed. Spikelets obovoid,
villous: first glume wanting: second glume and sterile lemma subequal, broad,
5-nerved, the sterile lemma with a small palea and sometimes a staminate flower:
fertile lemma cartilaginous, boat-shaped, 3-nerved, subacute, chestnut-brown, as
long as the glume, the pale margins very narrow.-Two species, natives of the
S United States.
Leaf-blades erect, or spreading at the apex, linear, folded at base: panicle usually
purple. 1. A. rufa.
Leaf-blades ascending or spreading (on the average shorter and broader
than in A. rufa), tapering to the apex, rounded at base: panicle
usually pale. 2. A. villosa.
1. A. rufa (El.) Schult. Stem slender,
erect; 0.6-1.2 m. tall: lower sheaths
crowded, keeled, often purplish; leaf-blades
mostly 20-50 cm. long, 2-4 mm. wide:
panicle 8-15 cm. .long, 1.5-3 cm. wide,
brownish at maturity, the slender erect
branches spikelet-bearing throughout; spike-
lets 3-4 mm. long, the copious pubescence
in stripes down the middle of the inter-
nerves.-Moist pinelands, Coastal Plain, Fla.
to Tex. and N. C.
2. A. villosa (Michx.) Beauv. Differs from
A. rufa in the short lower sheaths, shorter,
wider leaf-blades and paler, more open
panicle.-Dry pinelands, Coastal Plain, Fla.
to E Tex. and N. C.
19. VALOTA Adans. Perennials from knotty pubescent crowns, the
slender racemes erect or nearly so, aggregated along the upper part of the main
axis, forming a white or tawny silky panicle. Spikelets lanceolate, in pairs,
short-pedicelled in 2 rows along one side of a narrow rachis: first glume minute,
glabrous: second glume and sterile lemma
about as long as the fruit, 3-5-nerved, co-
piously silky: fertile lemma cartilaginous,
lanceolate, acuminate, brown, the flat white
hyaline margins broad.-About 12 species, in
temperate and tropical America.
1. V. insularis (L.) Chase. Stem 1-1.5 m.
tall, rather stout: leaf-blades as much as 30 /j
cm. long and 1.5 cm. wide: panicle 15-30
cm. long, more or less nodding. [Trichachne
insularis Nees Panicum leucophaeum H.B.K.]
-(SILKY-GRASS.)-Moist soil and waste-
places, Coastal Plain, Fla. and S Tex.-(W. I., Mex., C. A., S. A.)
20. SYNTHERISMA Walt. Erect or prostrate annuals or perennials, the
slender racemes digitate or aggregate on a short axis. Spikelets in 2 's or 3 's,
subsessile or short-pedicelled, alternate in 2 rows on one side of a 3-angled rachis,
lanceolate or elliptic: first glume minute or wanting: second glume equalling
the sterile lemma or shorter: fertile lemma cartilaginous, the hyaline margins
pale. [Digitaria Haller]-About 60 species, in tropical and temperate regions.
-FINGER-GRASSES. CRAB-GRASSES.-Some species are etrnicious weeds.
Rachis of raceme winged, or flat-margined: creeping annuals. I. SANGUINALIA.
Rachis of raceme wingless, triangular: plants not creeping, an-
nual or perennial. II. FILIFORMIA.
Rachis bearing scattered long, fine hairs (these rarely wanting) : spikelets narrow,
acuminate, nearly glabrous. 1. S. digitatum.
Rachis not bearing hairs.
Leaf-sheaths glabrous: fertile lemma brown.
Spikelets 2 mm. long. 2. S. Ischaemum.
Spikelets 1.7 mm. long. 3. S. floridanum.
Leaf-sheaths hispid or villous: fertile lemma pale.
Spikelets 1.5 mm. long: pedicels terete, glabrous. 4. S. serotinum.
Spikelets 2.5-3.5 mm. long: pedicels angled, scabrous.
Second glume much smaller than the spikelets; first
glume present. 5. S. sanguinale.
Second glume equalling the spikelets; first glume ob-
solete. 6. S. Simpsoni.
Fertile lemma pale or gray: plant perennial. 7. S. pauciflorum.
Fertile lemma dark-brown: plant erect or at least not rooting at
decumbent base, annual or sometimes apparently perennial.
Second glume and sterile lemma glabrous. 8. S. gracillimum.
Second glume and sterile lemma glandular-pubescent.
Spikelets about 1.5 mm. long.
Leaf-blades folded or involute, flexuous. 9. S. paniceum.
Leaf-blades flat. 10. S. filiforme.
Spikelets 2-3 mm. long. 11. S. villosum.
1. S. digitatum (Sw.) A. Hitche. Plant decumbent and spreading, with the
aspect of S. sanguinale: stem as much as 60 cm. long or rarely 100 cm.: leaf-
sheaths papillose-hirsute: racemes slender, mostly 5-10, aggregate, spread-
ing, 5-10 cm. long: spikelets about 2 mm. long: first glume minute; second
glume half as long as the spikelet, both
sparingly appressed-pubescent: fruit slightly
shorter than the sterile lemma, pale. [S. se-
tosum Nash]-Waste-places, Coastal Plain,
C and S Fla. and Ala.-(W. I., Mex.,
C. A., S. A.)
2. S. Ischaemum (Schreb.) Nash. Plant i
decumbent and spreading or at first erect: I
stem usually less than 50 cm. tall: leaf-
sheaths smooth: racemes 2-6, rarely more,
mostly 4-7 cm. long: spikelets about 2 mm.
long, usually purplish: first glume wanting:
second glume and sterile lemma equal, glan-
dular-pubescent, as long as the dark fruit.
[S. humifusum Rydb. Panicum glabrum
Gaud.]-Waste-places, various provinces, S. C. to Ark., S. D., and Me.; oc-
casional westward. Nat. of Eu.-(W. I.)
3. S. floridanum A. Hitchc. Differs from S. Ischaemum in the smaller spike-
lets (1.7 mm. long, 0.6 mm. wide) and the less pubescent second glume and
sterile lemma, the hairs not being glandular.-Sandy pinelands, Hernando Co.,
4. S. serotinum Walt. Plant creeping, sometimes forming extensive mats:
flowering stem usually not more than 30 cm. tall: leaves crowded on the creep-
ing stems, the sheaths villous, the blade 1-2 cm. long, 3-5 mm. wide: racemes
usually 3-5, slender, often arcuate, usually 3-6 cm. long: spikelets pale,
crowded: first glume wanting: second glume about one-third as long as the
sterile lemma, both pubescent. [Panicum serotinum Michx.]-Pasture and
waste-places, Coastal Plain, Fla. to La. and N. C.-(W. I.)
5. S. sanguinale (L.) Dulac. Plant decumbent and spreading, often purplish:
stem rooting at the lower nodes, as much as 1 m. long: leaf-sheaths papillose-
pilose: racemes several to many, 3-15 cm. long, digitate at the summit of the
stems and usually one or more whorls a short distance below: spikelets usually
about 3 mm. long: first glume minute, triangular, glabrous: second glume about
half as long as the sterile lemma, both appressed-pilose, the hairs becoming
spreading, or the sterile lemma glabrous. [Panicum sanguinale L. S. fimbriatum
Nash S. marginatum Nash S. barbatum Nash]-(CRAB-GRASS.)-Fields, pas-
tures, and waste-places, throughout E U. S.-(W. I., Mex., C. A., S. A., 0. W.)
6. S. Simpsoni (Vasey) Nash. Stem creeping and rooting at the lower nodes,
as much as 1-1.5 m. long: leaf-sheaths papillose-pilose, those of the innova-
tions compressed and keeled: racemes 4-8, ascending, pale, 8-12 cm. long:
spikelets about 3 mm. long: second glume and sterile lemma finely nerved, as
long as the fertile lemma.-Sandy fields, Fla.-(Cuba.)
7. S. pauciflorum A. Hitchc. Plant perennial: stem erect or somewhat decum-
bent at base, 0.5-1 m. tall, very slender: leaf-sheaths and blades grayish-
villous: racemes 2-3, ascending or erect, 5-11 cm. long, the filiform rachis
naked for 1-5 cm. at base: spikelets rather distant, elliptic, about 3.2 mm.
long, glabrous: first glume minute, with a hyaline erose margin: second glume
and sterile lemma finely nerved, as long as the grayish fertile lemma.-Pine-
lands, S Fla.
8. S. gracillimum (Scribn.) Nash. Stem 0.5-1 m. tall: leaf-sheaths appressed-
pilose: blades long and narrow, 1-2 mm. wide, often involute: racemes 2-sev-
eral, slender, ascending or erect, 10-30 cm. long: spikelets about 2 mm. long,
often in 3's, the longer pedicels as much as 5 mm. long: first glume wanting:
second glume half to three-fourths as long as the sterile lemma. [S. Bakeri
Nash]-Dry pinelands, Fla.
9. S. paniceum (Sw.) Nash. Stems commonly in dense tufts, 0.3-1 m. tall:
leaf-sheaths appressed-pubescent or glabrous: blades about 1 mm. wide,
slender, often folded or involute, the older ones usually flexuous: racemes
mostly 1-3, erect, 5-20 cm., commonly 10-15 cm. long.-Moist soil, pinelands
or open grounds, S Fla.-(W. I.)
10. S. filiforme (L.) Nash. Stems usually in small tufts, rarely as much as
0.6 m. tall: leaf-sheaths pilose: blades usually less than 10 cm. long: racemes
1-5, erect or ascending, usually not over 10 cm. long: spikelets rather crowded:
first glume wanting: second glume somewhat shorter than the sterile lemma,
both densely pubescent with crisp glandular-tipped whitish hairs: fertile
lemma somewhat acuminate. [Panicum filiforme L.]-Sandy fields and open
grounds, Coastal Plain and adj. provinces, Fla. to Tex., Kans., and Mass.
Nat. of Eu.-(W. I., Mex.)
11. S. villosum Walt. Differs from S. filiforme in being taller (as much as
1-1.5 m.) and apparently perennial, the leaf-blades longer, the racemes more
numerous (5-7) and longer (as much as 25 cm.), and in the larger spikelets
(2-3 mm.).-S. leucocoma Nash is a form with few racemes and silky spike-
lets.-Sandy fields and woods, Coastal Plain, Fla. to E Tex., Okla., Ill., and
S Va.-(W. I., Mex.)
21. LEPTOLOMA Chase. Branching perennials with brittle culms, felty
pubescent at base, flat blades and open or diffuse panicles, these breaking
away at maturity, becoming tumble-weeds. Spikelets lanceolate, on slender
pedicels: first glume minute or obsolete: second glume 3-nerved, nearly as long
as the 5-7-nerved sterile lemma, a stripe of appressed silky hairs down the
internerves and margins of each: fertile
lemma cartilaginous, elliptic, acute, brown,
the delicate hyaline margins enclosing the
palea.-Four species, Australian, except the
1. L. cognatum (.Schult.) Chase. Stem de-
cumbent at base, 20-50 cm. long: leaf-
blades mostly less than 10 cm. long: panicle
10-20 cm. long, becoming nearly as wide:
spikelets about 3 mm. long, borne singly at
the ends of capillary branchlets. [Panicum
cognatum Schult. P. autumnale Bosc.]-
(WITCH-GRASS.)-Sandy open grounds, va-
rious provinces, Fla. to Tex., Ariz., Kans., and Vt.-(Mex.)
22. ERIOCHLOA H. B. K. Annuals or perennials with terminal panicles
consisting of several to many spreading or appressed racemes, usually rather
closely arranged along the main axis. Spikelets more or less pubescent, soli-
tary or sometimes in pairs, short-pedicelled or subsessile in 2 rows on one side
of a narrow, usually hairy rachis, the pedicels often clothed with long stiff
hairs, the back of the fertile lemma turned from the rachis: lower rachilla-
joint thickened, forming a more or less ring-like callus below the second glume,
the first glume reduced to a minute sheath adnate to it: second glume and
sterile lemma about equal, acute or acuminate, the lemma usually enclosing a
hyaline palea or sometimes a staminate
flower: fertile lemma indurate, minutely
papillose-rugose, mucronate or awned, the
margins slightly inrolled.-Fifteen species,
in the warmer regions, but mostly Ameri-
1. E. Michauxii (Roem. & Schult.) A.
Hitchc. Plant perennial: stem erect, single,
puberulent about the nodes, 70-150 cm. tall:
leaf-blades usually 20-40 cm. long, (very
narrow, and with few racemes and empty
sterile lemma in E. Michauxii Simpsoni):
racemes ascending or spreading: spikelets
about 5 mm. long. [E. mollis Michx. E. longifolia Vasey E. mollis longifolia
Chapm.]-Wet soil, Coastal Plain, Fla. and S Ga.
23. BRACHIARIA (Trin.) Griseb. Annuals or perennials, with terminal
inflorescence of several racemes along a common axis: spikelets dorsally com-
pressed, solitary, rarely in pairs, subsessile, in two rows on one side of a
3-angled, sometimes narrowly winged rachis, the first glume turned toward the
axis; first glume short or nearly as long as the spikelets: second glume and
sterile lemma about equal, 5- to 7-nerved, the lemma enclosing a hyaline palea
and sometimes a staminate flower: fertile lemma indurate, usually papillose-
rugose, the margins inrolled, the apex rarely mucronate or bearing a short awn.
-Fifteen species, in the warmer regions of both hemispheres.
Anastomosing veins of spikelet prominent. 1. B. extensa.
Anastomosing veins of spikelet obscure or wanting. 2. B. plantaginea.
1. B. extensa Chase. Plant annual, nearly glabrous throughout: stem branch-
ing, decumbent and rooting at base, 40-60 cm. long: leaf-blades flat, mostly
not over 10 cm. long, 8-12 mm. wide: spikes
2-5, spreading, 3-7 cm. long, distant on the
axis: spikelets about 4 mm. long, the second
glume and sterile lemma pointed beyond
the turgid fruit. [B. platyphylla Nash]-
Moist fields, Coastal Plain, Fla., La., and
Tex.-(W. I., S. A.)
2. B. plantaginea (Link) A. Hitchc. Dif-
fers from B. extensa in having the anas-
tomosing veins of the spikelet obscure or
wanting and the second glume and sterile
lemma not pointed beyond the fruit.-OpenI i
moist ground, various provinces, Ga. to Pa.
and N. J.-(Mex., S. A.)
24. AXONOPUS Beauv. Our species stoloniferous or tufted glabrous
perennials, with usually flat abruptly rounded or somewhat pointed leaf-blades,
and 2-4 slender spike-like digitate racemes. Spikelets depressed biconvex, not
turgid, oblong, usually obtuse, solitary, sessile and alternate in 2 rows on one
side of a 3-angled rachis, the back of the fertile lemma turned from the axis:
first glume wanting: second glume and sterile lemma equal, the former without
a palea: fertile lemma indurate, oblong-elliptic, obtuse, the margins of the
lemma slightly inrolled.-About 30 species, mostly natives of tropical America.
Spikelets 2-2.5 mm. long, obscurely silky pubescent: midnerve
suppressed. 1. A. compressus.
Spikelets more than 4 mm. long, glabrous: midnerve evident. 2. A. furcatus.
1. A. compressus (Sw.) Beauv. Tufted, often producing long leafy stolons
with short broad obtuse leaf-blades: flowering stem 20-40 cm. tall: leaf-
sheaths compressed: racemes mostly 2 or 3,
spreading, 3-10 cm. long, long-exserted on
slender peduncles, terminal and axillary:
spikelets 2-2.5 mm. long. [Anastrophus com-
pressus Schlecht. A. platycaulis Nash Pas-
palum platycaule Poir.]-(CARPET-GRASS.)-
Moist open ground, Coastal Plain, Fla. to
E Tex., Ark., and N. C.--(W.I., Mex.,
2. A. furcatus (Fliigge) A. Hitchc. Plant
usually larger than A. compresses, the stems
few in a tuft, extensively stoloniferous:
racemes 2, 5-15 cm. long: second glume and
sterile lemma conspicuously pointed beyond
the fruit: foliage rarely pubescent. [Ana-
strophus paspaloides Nash Paspalum furcatum Fliigge]-Moist pinelands and
open grounds, Coastal Plain, Fla. to Tex. and Va.
25. REIMAROCHLOA A. Hitchc. Spreading or stoloniferous perennials
with flat leaf-blades and slender subdigitate racemes, stiffly spreading or re-
flexed at maturity. Spikelets strongly dorsally compressed, lanceolate, acumi-
nate, rather distant, subsessile and alternate in two rows along one side of a
narrow, flattened rachis, the back of the fertile lemma turned toward it: both
glumes wanting, or the second sometimes
present in the terminal spikelet: sterile
lemma about equalling the fruit, the sterile
palea obsolete: fertile lemma scarcely in-
durate, faintly nerved, acuminate, the mar-
gins inrolled at the base only, the palea
free nearly half its length.-Four species,
natives of tropical America.
1. R. oligostachya (Munro) A. Hitchc. '.
Plant glabrous: stem compressed, 40-80 cm. I I
long: racemes 1-4, 5-7 cm. long: spikelets
about 5 mm. long. [Reiimaria oligostachya Munro]-In water or wet soil,
26. PASPALUM L. Mostly perennials, with 1 to many spike-like racemes,
these single or paired at the summit of the stem or racemosely arranged along
the main axis. Spikelets plano-convex, usually obtuse, subsessile, solitary or in
pairs, in two rows on one side of a narrow or dilated rachis, the back of the
fertile lemma toward it: first glume usually wanting: second glume and sterile
lemma commonly about equal: fertile lemma usually obtuse, chartaceous-
indurate, the margins inrolled.--Over 300 species, widely distributed in the
warmer parts of both hemispheres.
Rachis with broad green membranous wings. (Subgenus CERESIA.)
Rachis not winged or very narrowly so.
Racemes in pairs at the summit of the stem, rarely a third
one'below, divaricate at maturity: spikelets solitary.
Spikelets narrowly ovate, 3-4.5 mm. long.
Spikelets nearly circular, 1.5 mm. long.
Racemes 1-many, racemose on the axis, not in pairs at the
Spikelets not over 2 mm. long (except in no. 6) : slen-
der leafless flowering branches borne in the upper
sheaths (except in nos. 7-10).
Spikelets over 2 mm. long: branches, if any, leafy.
First glume usually present on one of each pair of
spikelets, sometimes on both: plants producing
First glume wanting.
Spikelets glabrous: leaf-blades flat or folded,
5-12 mm. wide.
Spikelets with a silky fringe around the margin,
Fruit dark brown at maturity
Racemes not more than 6, usually 3 or 4: spikelets broadly ovate: rachis not extend-
ing beyond the uppermost spikelet. 1. P. dissectum.
Racemes numerous : spikelets about half as broad as long:
rachis extending as a point beyond the spikelet. 2. P. repens.
Sterile lemma wrinkled in the internerves: spikelets
glabrous, flattened. 3. P. vaginatum.
Sterile lemma not wrinkled: second glume pubescent. 4. P. distichum.
Plant stoloniferous; widely creeping.
5. P. conjugatum.
First glume present in at least one of each pair of spike-
lets: spikelets obovate, appressed-pubescent, 2-2.5 mm.
or more long. 6. P. Langei.
First glume wanting: spikelets not over 2 mm. long.
Racemes 3-9, scarcely longer than the corresponding
internode of the axis: leaf-sheath with an erect
pointed auricle on each side at the summit:
axillary racemes rarely present.
Spikelets about 1.3 mm. long, obovate, blunt,
crowded, glandular-pubescent. 7. P. Blodget
Spikelets 1.5-2 mm. long, elliptic.
Racemes 2-3 cm. long, relatively thick. 8. P. caespitc
Racemes 5-10 cm. long, slender. 9. P. laxum.
Racemes 1 or 2, rarely 3, 2 or 3 times longer than the
axis internodes: leaf-sheaths not auricled
(rarely so in P. ciliatifolium) : stems slen-
Spikelets not over 1.8 mm. long (if as much as
1.8 mm., leaf-blades either pubescent
on the surface or clustered at the
base). 10. P. longepe
Spikelets 1.6-1.8 mm. long, oval: leaf-
blades conspicuously villous, usually
3-10 mm. wide. 11. P. debile.
Spikelets about 1.5 mm. long, orbicular:
leaf-blades short-pilose, usually not
over 4 mm. wide. 12. P. setaceui
Spikelets 2 mm. long(or less in P. ciliatifolium).
Leaf-blades linear, rarely over 4 mm. wide,
firm, glabrous. 13. P. rigidifol
Leaf-blades lanceolate to linear, if the lat-
ter pubescent on both surfaces.
Leaf-blades glabrous or with occasional
cilia, 8-16 mm. wide.
Leaf-blades firm, tapering from the
subcordate base to summit: plants
Leaf-blades thin, tapering toward
base and summit: sheaths gla-
brous or margin ciliate: spikelets
1.8-2 mm. long.
Leaf-blades pubescent on one or both
Leaf-blades on both surfaces sparsely
pilose with long hairs, rather thin.
Leaf-blades densely pubescent on
Racemes solitary or rarely 2 : spikelets subsessile, crowded.
Racemes 2-5: spikelets long-pedicellate, loose.
Plant erect or ascending, not stoloniferous nor with leafy
branches: spikelets blunt, mostly solitary.
Spikelets more or less flattened.
Spikelets %-% as thick as broad: glume and
sterile lemma firm.
Spikelets rarely over 2.8 mm. long, longer than
broad, more than % as thick: panicle
much exceeding the blades.
Leaf-sheaths glabrous or ciliate only.
Leaf-sheaths and.blades pilose.
Spikelets 3-3.2 mm. long, circular, not more
than 13 as thick: leaf-blades equalling the
base of the panicle or overtopping it.
Spikelets flattened, not more than 1/ as thick as
broad, closely imbricate, often in pairs:
glume and sterile lemma thin, the cells vis-
ible: short scaly rootstocks present.
Plant glabrous or nearly so: spikelets 2.2-2.8
Plant villous: spikelets 2.7-3.4 mm. long.
Spikelets turgidly plano-convex: glume and sterile
Leaves clustered toward the base of the stem;
rarely over 15 cm. long, the upper half of
the stem appearing naked: stems less than
1 m. tall, usually 75 cm. or less, mostly as-
Leaves scattered along the stem; some of the
blades, at least, 20 cm. long, commonly much
longer: stems usually 1-2 m. tall, erect.
Glume and sterile lemma not inflated and
wrinkled, commonly rusty-tinged: racemes
usually long and widely spreading at ma-
turity: leaf-blades flat, 1.2-2.3 cm. wide, the
base wider than the sheath.
Glume and sterile lemma slightly inflated and
wrinkled, not rusty-tinged: racemes erect or
ascending: leaf-blades firm, commonly folded,
the base not wider than the sheath, rarely as
Plant decumbent at base, rooting at the nodes, or sto-
loniferous (occasional plants in dry situations erect
from the base), producing leafy branches: rachis
about 2 mm. wide: spikelets in pairs, acute or sub-
acute. (See also no. 26.)
Spikelets depressed piano-convex, not over 1.5 mm.
wide; leaf-sheaths keeled: blades rarely over 5 mm.
wide, usually folded at base: racemes ascending or
Spikelets turgidly plano-convex, 2 mm. or more wide:
leaf-sheaths not keeled: blades more than 7 mm.
wide (usually 10 mm. or more), flat.
Panicle virgate, the usually numerous racemes suberect:
spikelets scarcely over 2 mm. long.
14. P. propinquum.
15. P. ciliatifolium.
16. P. pubescens.
17. P. supinum.
18. P. monostachyum.
19. P. bifidun.
20. P. laeve.
21. P. longipilumn.
22. P. circular.
23. P. praecox.
24. P. lentiferumn.
25. P. difforme.
26. P. giganteum.
27. P. floridanum.
28. P. lividum.
29. P. pubiflorum.
30. P. Urvillei.
Panicle lax, the few to several racemes more or less
spreading: spikelets about 3.5 mm. long. 31. P. dilatatum.
Spikelets about 2 mm. long, nearly as broad, glabrous:
rachis 1.5-2 mm. wide: plant annual. 32. P. Boscianum.
Spikelets 3 mm. long: rachis 1 mm. or less wide: plant
perennial 33. P. plicatulum.
1. P. dissectum L. Glabrous creeping subaquatic perennial: stem 20-60 cm.
long: leaf-blades 3-6 cm. long, 4-5 mm. wide: racemes usually erect, 2-3 cm.
long, the rachis 2-3 mm. wide: spikelets 2
mm. long, obovate, pale, glabrous. [P. mem- /
branaceum Walt. P. Walterianim Schult.]
-Muddy banks, ditches, wet sandy places,
and in shallow water, Coastal Plain and
rarely adj. provinces, Fla. to Tex., Mo.,
and Del.--(W. I.)
2. P. repens Berg. Aquatic perennial with
submerged stems as much as 200 cm. long,
and numerous floating branches with inflated
sheaths: leaf-blades 10-20 cm. long, 12-15
mm. wide: racemes ascending, spreading or
recurved, rather lax, 3-5 cm. long, the rachis
about 1.5 mm. wide: spikelets 1.4-2 mm.
long, elliptic. [P. mucronatum Muhl. P.
fluitans Kunth]-Ponds, marshes, and streams, Coastal Plain, Fla. to Tex.,
Ill., and S. C.-(W. I., Mex.)
3. P. vaginatum Swartz. Stem producing creeping rootstocks and also stolons
100 cm. or more long, the flowering shoots 8-60 cm. tall: leaf-sheaths inflated;
blades 3-8 mm. wide: racemes usually 2, at first erect, finally spreading or
reflexed: spikelets 3-4.5 mm. long, acute, pale. [P. reimaTioides Chapm.]-
(SALT JOINT-GRASS.)-Seacoasts and brackish marshes, Coastal Plain, Fla. to
Tex. and N. C.-(W. I., Mex., C. A., S. A.)
4. P. distichum L. Resembling P. vaginatum: leaf-sheaths usually less inflated
and papery: spikelets less flattened, first glume often present on some of the
spikelets.-(JoINT-GRASS.)-Ditches, fresh or brackish marshes and prairies,
Coastal Plain and Basin and Range, Fla. to Tex., Calif., Okla., and N. J.-
(W.I., Mex., C. A., S. A.)
5. P. conjugatum Berg. Perennial, extensively creeping: stems compressed:
flowering-branches as much as 100 cm. tall: leaf-blades flat, thin, about 1 cm.
wide: racemes widely divaricate, usually arcuate, slender, 10-12i cm. long:
spikelets 1.5 mm. long, flat on both sides, pald-yellow, silky-pubescent around the
margin.-Moist ground, Coastal Plain, Fla. to Tex.-(W. I., Mex., C. A., S. A.)
6. P. Langei (Fourn.) Nash. Stem 70-110 cm. tall: leaf-sheaths glabrous or
sometimes hirsute, ciliate; blades flat, as much as 1.5 cm. wide: racemes 2 or 3,
7-9 cm. long: spikelets obovate, 2.5-2.8 mm. long. [Dimorphostachys ciliifera
Nash]-Moist woods and thickets, Fla. to Tex.-(W. I.)
7. P. Blodgettii Chapm. Stem erect, as much as 100 cm. tall: leaf-sheaths gla-
brous or the lower appressed villous; blades 2-15 mm. wide, glabrous, often
ciliate: racemes 3-15, spreading or ascending. [P. gracillimum Nash]-Pine-
lands and hammocks, Everglade Keys, and adj. Everglades, Fla. and Florida
8. P. caespitosum Fliigge. Stem 30-60 cm. tall: leaf-sheaths glabrous; blades
3-7 mm. wide, glabrous, flat, usually subinvolute in drying, narrowed at both
ends: racemes 2-6: spikelets sparsely appressed-pubescent.-Pinelands, Ever-
glades, and hammocks, S pen. Fla. and the Keys.-(W. I.)
9. P. laxum Lam. Stem 60-100 cm. tall: leaf-sheaths glabrous, a few long
white hairs at the mouth: blades folded or involute: racemes few to several,
mostly arcuate-divaricate: spikelets crowded, 1.8-2 mm. long, pubescent or
rarely glabrous. [P. elatum (Fl. SE. U. S.)]-Rocky hammocks, Key West,
10. P. longepedunculatum Le Conte. Stem spreading, 25-80 cm. tall: leaf-
sheaths glabrous, ciliate: blades 4-10 mm. wide, the margin ciliate: racemes
1 or 2, 2-8 cm. long, slender, usually curved: spikelets 1.5 mm. long. [P. ken-
tuckyense Nash]-Pinelands, fields, and woods, Coastal Plain and rarely adj.
provinces, Fla. to Miss. and Ky.
11. P. debile Michx. Stem 40-100 cm. tall: leaf-sheaths villous; blades 3-10
mm. wide: racemes usually single, 7-11 cm. long: spikelets glandular-pubescent.
[P. villosissimum Nash]-Pinelands and fields, Coastal Plain, Fla. to Tex.
and N. Y.
12. P. setaceum Michx. Stem 20-70 cm. tall: leaf-sheaths villous; blades
linear, 2.5-5 mm. wide: racemes usually single: spikelets glabrous or- sparsely
glandular-pubescent.-Meadows, fields, pinelands, and woods, various provinces,
Fla. to Tex. and N. Y.
13. P. rigidifolium Nash. Stem erect, 30-80 cm. tall: lower leaf-sheaths vil-
lous; blades erect or ascending: racemes usually single, 6-13 cm. tall: spikelets
about 2 mm. long, glabrous or pubescent.-Pinelands, Coastal Plain, Fla. to
14. P. propinquum Nash. Stem 50-100 cm. tall: leaf-sheaths glabrous; blades
glabrous or sparingly ciliate, 7-20 mm. wide: racemes 1-3, 6-12 cm. long:
spikelets glabrous, about 2 mm. long.-Hammocks, moist banks, and thickets,
sandy soil, Coastal Plain, Fla. to Tex.
15. P. ciliatifolium Michx. Stem 40-80 cm. tall: leaf-blades 6-15 mm. wide:
racemes 1 or 2, 5-11 cm. long: spikelets glabrous or pubescent. [P. blepharo-
phyllum Nash P. Chapmanii Nash P. Eggertii Nash P. epile Nash P. latifolium
Le Conte]-Fields, pinelands, hammocks, open woods, and swamps, Coastal Plain
and adj. provinces, Fla. to Tex. and N. J.-(W. I.)
16. P. pubescens Muhl. Stem 40-80 cm. tall, usually pilose below the racemes:
leaf-blades linear: racemes usually single, 6-12 cm. long: spikelets about 2 mm.
long, glabrous. [P. Muhlenbergii Nash]-Fields, acid swamps, and marshes,
Coastal Plain and rarely adj. provinces, Fla. to Tex. and Vt.
17. P. supinum Bose. Stem 20-60 cm. tall: leaf-blades 10-20 mm. wide:
racemes usually 2 or 3, 4-10 cm. long: spikelets about 2 mm. long, glandular-
pubescent, or sometimes glabrous. [P. dasyphyllum Ell.]-Sandy soil, pine-
lands, fields, banks, and swamps, Coastal Plain, Fla. to La., Tenn., and N. C.
18. P. monostachyum Vasey. Glabrous: stem strict, 60-120 cm. tall: leaf-
blades elongate, terete: racemes mostly 10-30 cm. long: spikelets 3 mm. long.
[P. solitarium Nash]-Wet soil, prairies and marshes, Coastal Plain, S Fla.
19. P. bifidum (Bertol.) Nash. Stem erect, 70-130 cm. tall: leaf-sheaths
mostly papillose-hirsute; blades 5-10 mm. wide, glabrous beneath, hirsute above
toward the base: racemes 2-5, 7-15 cm. long, erect; the rachis very slender,
flexuous: spikelets turgid, 3.5-4 mm. long. [P. racemulosum Nutt.]-Dry pine-
lands, sandy woods, shaded banks, and thickets, Coastal Plain, Fla. to Tex.
and S. C.
20. P. laeve Michx. Stem erect or ascending, glabrous, 40-100 cm. tall: leaf-
blades glabrous, or sparsely pilose on the upper surface: racemes 2-5, usually
3 or 4, 3-10 cm. long, spreading or ascending: spikelets 2.5-3 mm. long. [P.
angustifolium Le Conte P. australe Nash]-Fields, woods, swamps, and mea-
dows, various provinces, Fla. to Tex. and N. J.
21. P. longipilum Nash. Resembling P. laeve: leaf-blades pilose on both sur-
faces or nearly glabrous beneath: racemes 2-6, rather lax and spreading.
[P. plenipilum Nash P. praelongum Nash]-Moist sandy soil, pinelands,
woods, and marshes, Coastal Plain, Fla. to Tex., Tenn., and N. Y.
22. P. circulare Nash. Stem 30-60 cm. tall: leaf-sheaths sparsely pilose or
the upper glabrous; blades 5-10 mm. wide, usually more or less pilose: racemes
2-4, 5-10 cm. long, mostly suberect or the lower spreading.-Fields, marshes,
meadows, prairies, and sandy woods, Coastal Plain and occasionally adj. prov-
inces, N. C. to Tex., Kans., and Conn.
23. P. praecox Walt. Stem 50-100 cm. tall, producing short scaly rootstocks:
leaf-sheaths glabrous or the lower pilose; blades 3-7 mm. wide, glabrous, or
somewhat pilose on upper surface toward the base: racemes 2-8 (usually 4-6),
2-7 cm. long, ascending.-Wet pinelands, marshes, and ponds, Coastal Plain,
Fla. to Tex. and N. C.
24. P. lentiferum Lam. Resembling P. praecox, but commonly more robust,
the leaf-sheaths and blades often conspicuously pilose: racemes 2-9, usually
4 or 5, 3-10 cm. long. [P. Curtisianum Steud. P. glaberrimum Nash P. tardum
Nash P. Kearneyi Nash P. amplum Nash]-Moist pinelands, wet woods, and
marshes, Coastal Plain, Fla. to Tex. and N. C.
25. P. difforme LeConte. Stem 35-75 cm. tall: leaf-sheaths pilose on keel
and margin or glabrous; blades usually pilose on the upper surface at least
at base: racemes 2 or 3, 3.5-8 cm. long: spikelets mostly in pairs, 3.5-4 mm.
long, oval.-Low grounds and rich woods, Coastal Plain, Fla. to La., and Ga.
26. P. giganteum Baldw. Stem mostly solitary, 150-200 cm. tall, with short
scaly rootstocks: leaf-sheaths glabrous or pilose: racemes usually 3 or 4,
10-20 cm. long: spikelets 3-3.8 mm. long, oval or obovate, glabrous. [P. longi-
cilium Nash.]-Moist sandy soil or clay, pinelands, marshes, and ditches,
Coastal Plain, Fla. to Miss.
27. P. floridanum Michx. Stem 100-150 cm. tall, with short scaly rootstocks
(more robust and taller: foliage glabrous or nearly so: racemes averaging
longer, in P. floridanum glabratum. [P. altissimum Le Conte], Fla. to Tex.,
Kan., Md., and N. J.): leaf-sheaths commonly villous; blades 4-10 mm.
wide, usually villous at least above: racemes mostly 2-4, 4-12 cm. long: spike-
lets 3.6-4 mm. long, oval, glabrous.-Low sandy soil, pinelands, prairies,
swamps, and fields, Coastal Plain and rarely adj. provinces, Fla. to Tex., Mo.,
28. P. lividum Trin. Stem 60-100 cm. tall: leaf-sheaths usually glabrous;
blades 3-6 mm. wide, sometimes pubescent on the upper surface: racemes
usually 4-7, often flexuous, 1.5-5 cm. long.-Wet ground, Coastal Plain, Fla. to
Tex.-(W. I., Mex., C. A., S. A.)
29. P. pubiflorum Rupr. Stem 40-100 cm. tall, rather stout: leaf-sheaths
glabrous or the lower hirsute; blades 10-15 mm. wide, glabrous: racemes
usually 3-5, 5-10 cm. long: spikelets about 3 mm. long, softly pubescent
(stems often taller: spikelets glabrous in P. pubiflorum glabrum. [P. laevi-
glumis Scribn.], Woods, various provinces, Kans., Ind., and N. C.), broadly
obovate. [P. Hallii Vasey & Scribn. P. geminum Nash]-Moist soil, Coastal
Plain, La. to Tex.-(Mex.)
30. P. Urvillei Steud. Stems in large clumps, 100-150 cm. tall: lower leaf-
sheaths densely papillose-hirsute, purplish; blades 8-12 mm. wide: racemes 10-
20, 8-12 cm. long. [P. Vaseyanum Scribn.]-(VASEY-GRASS.)-Fields, low
grounds, prairies, and roadsides, Coastal Plain, Fla. to Tex. and S. C.-(C. A.,
31. P. dilatatum Poir. Stem 50-170 cm. tall: leaf-sheaths glabrous; blades
3-12 mm. wide: racemes 3-8, 5-10 cm. long.-(DALLIS-GRASS.)-Moist soil,
stream-banks, marshes, and waste-places, various provinces, Fla. to Tex., Tenn.,
and N. J.-(W. I., C. A., S. A.)
32. P. Boscianum Fliigge. Annual, glabrous as a whole, stems ascending from
a decumbent rooting base, 50-120 cm. long: leaf-sheaths purplish, the lower-
most hirsute; blades 3-10 mm. wide: racemes 2-9 cm. long: spikelets mostly
in pairs 2-2.3 mm. long, obovate. [P. purpurascens Ell.]-Moist soil, swamps,
cult. grounds, and hillsides, Coastal Plain, Fla. to Miss. and Pa.-(W7. I.)-
P. scrobiculatum (Fl. SE. U. S.)is a depauperate plant with solitary spikelets.
33. P. plicatulum Michx. Stem 50-100 cm. tall: leaf-sheaths keeled, glabrous
or rarely hirsute, the lower crowded: blades mostly folded at base, rather firm,
3-10 mm. wide: racemes usually 3-10 (2-19), 2-10 cm. long, usually arcuate-
spreading: spikelets drying brown, the sterile lemma wrinkled just inside the
margin.-Moist soil, pinelands, woods, and prairies, Coastal Plain, Fla. to Tex.
and Ga.-(W. I., Mex., C. A., S. A.)
27. PANICUM L. Annuals or perennials various in habit. Spikelets in
open or compact panicles, rarely in racemes: glumes 2, usually very unequal,
the first often minute, the second typically equalling the sterile lemma, the
latter enclosing a thin palea and sometimes a staminate flower: fertile lemma
chartaceous-indurate, typically obtuse, the nerves obsolete, the margins inrolled
over a palea of the same texture.-Five hundred species, in the warmer parts of
both hemispheres.-Sum.-fall, or all year S.-PANIC-GRASSES. WITCH-GRASSES.
Axis of branchlets extending beyond the base of the uppermost spikelet as a point or
bristle 1-6 mm. long: perennials: fruit transversely
rugose. I. DISTANTIFLORA.
Axis of branchlets not extending into a bristle. (In
Panicum genzinatum and P. paludivagum the some-
what flattened axis pointed but not bristle-form.)
Basal leaves similar to stem-leaves, not forming a
winter rosette: spikelets all fertile.
Fruit transversely rugose.
Plant annual: leaf-sheaths rather wide, flat:
spikelets more or less reticulate-veined. III. FASCICULATA.
Plant perennial: spikelets glabrous.
Inflorescence consisting of several spike-like
racemes along a main axis. II. GEMINATA.
Inflorescence an open panicle. VI. MAXIMA.
Fruit not transversely rugose.
First glume truncate or triangular-tipped, not
more than one fourth the length of the nar-
row, acute or acuminate, glabrous spikelet:
First glume not truncate (except in P. repens).
Spikelets glabrous, pointed: leaf-sheaths
papillose-hispid; leaves hirsute.
Spikelets warty: leaves glabrous.
Spikelets short-pediceled along one side of
the main branches of the panicle form-
ing narrow or spike-like racemes, some-
times somewhat aggregate toward the
ends of branches (see also VIII. Tenera).
First glume nearly equalling the sterile
First glume much shorter than the sterile
Panicle long (15-30 cm.), very narrow,
the branches erect or nearly so; fruit
rather thin and soft, the palea scarcely
Panicle usually open (at least not long
and narrow), the main branches
spreading: fruit indurate, the palea
enclosed: plants commonly produc-
ing axillary panicles.
Sterile palea not enlarged at ma-
Sterile palea enlarged at maturity,
forcing open the spikelet.
Spikelets in open or sometimes in contracted
or congested panicles, but the main
branches not in narrow or spike-like
racemes: stems simple.
Panicle narrow and few-flowered: stems
erect and wiry: leaf-blades drying in-
Panicle open or contracted, several- to
many-flowered: stems stout or rigid.
Basal leaves usually distinctly different from those of
the stem, forming a winter rosette: stems at first
simple, the spikelets of the primary panicle not
perfecting seed, later usually becoming much-
branched, the small secondary panicles with
cleistogamous, fruitful spikelets: panicles open,
the branchlets usually flexuous : perennials.
Leaf-blades elongate, not more than 5 mm. wide, 20
times as long as wide: autumnal phase branch-
ing from the base only.
Leaf-blades not elongate (or if so more than 5 mm.
wide and autumnal phase not branching from
Plant branching from the base, finally forming
rosettes or cushions, the foliage soft and lax:
leaf-blades prominently ciliate (except in P.
Plant branching from the stem-nodes or rarely
Leaf-blades long, stiff: autumnal phase bushy-
Spikelets turgid, attenuate at base, mostly
pustulose-pubescent: leaf-blades conspicu-
ously striate, tapering from base to apex.
Spikelets scarcely turgid, not attenuate at
base: leaf-blades tapering to both ends.
Leaf-blades not long and stiff (somewhat so in
P. oligosanthes, P. malacon, P. Commonsi-
anum, and P. equilaterale) : autumnal
phase usually not bushy-branched.
Spikelets turgid, blunt, strongly nerved (not
strongly turgid in P. oligosanthes) : leaf-
blades rarely as much as 1.5 cm. wide
(sometimes 2 cm. in P. Ravenelii).
Leaf-sheaths glabrous or minutely puberu-
lent: spikelets 1.5-2.5 mm. long, asym-
metrically pyriform, strongly nerved:
Leaf-sheaths, or some of them, papillose-
hispid: spikelets 3-4 mm. long.
Spikelets not turgid, blunt, nor strongly
nerved (see, however, P. roanokense and
Ligule of conspicuous hairs, usually 3-5
mm. long: spikelets pubescent.
Leaf-sheaths glabrous or only the lower-
most somewhat pubescent.
Leaf-sheaths strongly pubescent.
Ligule obsolete or nearly so (manifest in
P. tsugetorum and P. curtifolium).
Spikelets spheric at maturity: leaf-
blades glabrous, firm, cordate, with a
fine white margin: plants sparingly
branching: panicle-branches with vis-
Spikelets usually obovate or elliptic.
Leaf-blades of the mid-stem elongate,
less than 1.5 cm. wide: stems usu-
ally tall: spikelets pointed, ab-
ruptly so in the velvety P. sco-
Leaf-blades of the mid-stem not elon-
gate (somewhat so in P. equilat-
Blades cordate, 1-3 cm. wide (5-12
mm. in P. Ashei) : spikelets
Spikelets 2.5-3 mm. long: leaf-
sheaths glabrous or minutely
Spikelets 3-5 mm. long (some-
times but 2.7 mm. long in
the hispid-sheathed P. clan-
Blades not cordate (somewhat in
P. annulum), less than 1 cm.
Sheaths crisp- or appressed-pu-
bescent: blades firm : spikelets
Sheaths glabrous (sparsely pi-
lose in P. curtifolium and
the lower ones velvety in
P. mattamuskeetense and
often in P. annulum).
Vernal stems delicate (some-
times scarcely so in P. albo-
marginatum and P. tenue) :
spikelets 1.5 mm. long or less
(1.6-1.7 mm. in P. tenue).
Vernal stems slender but not
delicate, rarely less than
40 cm. high: spikelets 2-
2.9 mm. long (1.5 mm.
in P. microcarpon and P.
Lower internodes short, up-
per elongate, producing a
nearly naked stem, leafy
at base: spikelets nar-
rowly ovate, 2.7-2.9 mm.
Lower internodes not short:
vernal stems about evenly
leafy throughout: spike-
lets elliptic or obovate,
not more than 2.5 mm.
Plant slender, erect, with narrow erect or appressed
1. P. Chapmani.
Nodes bearded: leaf-sheath villous.
Nodes glabrous: plants glabrous throughout.
Spikelets 3 mm. long: glumes and sterile lemma
Spikelets not over 2.4 mm. long: glumes and sterile
lemma not papery.
Spikelets 2-4 mm. long.
Spikelets strongly reticulate-veined, 2-3 mm. long:
Spikelets scarcely reticulate-veined or only near apex.
Spikelets not over 2 mm. long, glabrous.
Spikelets over 3 mm. long, pubescent.
Spikelets 5-6 mm. long.
Panicles drooping: spikelets 4.5-5 mm. long.
Panicles erect: spikelets less than 3.5 mm. long.
Panicles more than half the length of the entire
Panicles narrow, usually less than half as broad
Panicles as broad as long.
Panicles not more than one-third the entire height
of the plant.
Stem stout: leaf-blades about 1 cm. wide: spike-
Stem slender: leaf-blades not over 6 mm. wide:
spikelets not turgid.
Plant large, rather coarse, with ample panicles.
Spikelets not over 2.5 mm. long, first glume less than
half the length of the spikelet.
Panicles loosely flowered: first glume truncate, about
one-fifth the length of the spikelet.
Panicle rather densely flowered: first glume triangu-
lar, about one-third the length of the spikelet.
Spikelets ,3-7 mm. long (sometimes less than 3 mm. in
P. virgatum cubense) : first glume more than half
the length of the spikelet.
Panicles elongate, strongly contracted: seacoast
Stem rarely 1 m. high, solitary from the nodes
of the horizontal rootstock.
Stem 1-2 m. high, in dense tufts.
Panicles diffuse or only slightly contracted: plants
sometimes of salt marshes but not littoral.
Plant slender, stiffly erect, with narrow strict panicles.
Rootstock present: stem but little compressed : spikelets
set obliquely on their appressed pedicels.
Panicles open: spikelets 3.4-3.8 mm. long (shorter
in exceptional specimens).
Panicles more or less contracted: spikelets not over
2.8 mm. long.
Rootstock wanting: stem strongly compressed: leaf-
sheaths keeled: spikelets not obliquely disposed.
Ligules ciliate: basal leaves half as long as the stem
or more: panicle rather open, much exceeding
the upper leaves.
2. P. barbinode.
3. P. paludivagum.
4. P. geminatum.
5. P. fasciculatum.
7. P. adspersum.
8. P. texanum.
9. P. bartowense.
10. P. dichotomiflorum.
11. P. miliaceum.
12. P. flexile.
13. P. capillare.
14. P. Gattingeri.
15. P. philadelphicum.
16. P. maximum.
17. P. repens.
18. P. Gouini.
19. P. amarum.
20. P. amarulum.
21. P. virgatum.
22. P. tenerum.
23. P. anceps.
24. P. rhizomatum.
Spikelets not over 2.7 mm., usually 2.5 mm. long,
the first glume less than half that length:
ligules 2-3 mm. long.
Spikelets 3-3.5 mm. long: first glume two-thirds
to three-fourths that length: ligule less than
1 mm. long.
Ligules erose or lacerate, not ciliate: basal leaves in
short tufts, the upper usually nearly equalling
the terminal rather dense panicle.
Fruit stipitate: spikelets 2.5-2.8 mm. long, con-
Fruit not stipitate: spikelets not conspicuously
Spikelets 1.8-2 mm., in occasional specimens
2.2 mm. long: panicle-branches ascending
Spikelets about 2.5 mm. long: panicle-branches
erect or nearly so.
Plant erect or partly decumbent, with lax panicles and
small gaping spikelets.
Plant weak, often with reclining stems, the mature
panicle diffuse, with filiform branches and scattered
Spikelets about 3.5 mm. long, beaked.
Spikelets 3 mm. long or less.
Leaf-sheaths retrorsely pilose: spikelets papillose-pilose.
Leaf-blades glabrous or nearly so on the surface and
margin: spikelets 2.2 mm. long.
Leaf-blades ciliate and more or less pilose on the
surface: spikelets 2 mm. long.
Leaf-sheaths not retrorsely pilose: spikelets pubescent
Spikelets pubescent, about 2 mm. long.
Leaf-blades glabrous on the surface.
Leaf-blades pilose on the surface.
Nodes bearded: plant grayish-villous: autumnal leaf-
Spikelets 2 mm. long.
Spikelets 2.5-2.8 mm. long.
Nodes not bearded: plant villous only at base, or nearly
glabrous: autumnal leaf-blades involute or flat.
Autumnal leaf-blades flat: lower panicle-branches
spreading or deflexed.
Autumnal leaf-blades involute: lower panicle-
branches more or less ascending.
Spikelets 3.3-3.5 mm. long, pointed.
Spikelets less than 3 mm. long, not pointed, or
Plant glabrous or nearly so: autumnal stems
Spikelets subsecund along the suberect
Spikelets not subsecund : panicle loose and
Plant pubescent, at least on the lower half.
Spikelets about 2.4 mm., rarely only 2.1
mm. long: vernal leaf-blades 7-12 cm.
long; autumnal blades not falcate.
Spikelets not over 2 mm. long: vernal leaf-
blades 4-6 cm. long; autumnal blades
much crowded, falcate.
25. P. longifolium.
26. P. Combsii.
27. P. stipitatum.
28. P. agrostoides.
29. P. condensum.
30. P. hians.
31. P. verrucosum.
32. P. depauperatum.
33. P. linearifolium.
34. P. laxiflorum.
35. P. xalapense.
36. P. ciliatum.
37. P. Qolycaulon.
38. P. strigosum.
39. P. chrysopsidifolium.
40. P. consanguineum.
41. P. zngustifolium.
42. P. fusiforme.
43. P. neuranthum.
44. P. ovinum.
45. P. arenicoloides.
46. P. aciculare.
Plant with tufted stems and open panicles with few
Plant with erect or partly decumbent stems, the panicles
with spreading branches.
Nodes, at least the lower, bearded.
Spikelets 1.5-1.6 mm. long, glabrous (occasional in-
dividuals with pubescent spikelets).
Spikelets 2 mm. or more long.
Spikelets glabrous, 2 mm. long: autumnal form
Leaf-blades all velvety: autumnal form spar-
Leaf-blades glabrous, or only the lower pubes-
cent or velvety: autumnal form freely
Spikelets 2 mm. long: autumnal form pro-
Spikelets 2.2 mm. or more long: autumnal
form less profusely branching.
Lower leaf-sheaths and all nodes pu-
Leaf-sheaths and upper nodes glabrous.
Nodes not bearded (lower nodes pubescent in P. barbu-
Stems erect, never becoming vine-like.
Stems soon prostrate, vine-like: branches divari-
Plants bright-green; stems lax: spikelets not
over 2.1 mm. long.
Plants grayish-green; stems stiff: spikelets
2.5 mm. long.
Stem soon prostrate.
Plant bright-green; stems lax: spikelets not
over 2.1 mm. long.
Plant grayish-green; stems stiff: spikelets 2.5
Stem erect, or the autumnal form topheavy,
Spikelets not over 1.6 mm. long: panicles nar-
row: plants glaucous bluish-green.
Spikelets 2 mm. or more long: panicles open.
Leaf-blades erect, firm: spikelets turgid,
strongly nerved: plants grayish olive-
Leaf-blades spreading: spikelets not
Spikelets 2.2 mm. or more long,
pointed: sheaths bearing pale glan-
Spikelets not over 2 mm. long, not
Autumnal form erect, branched like
a little tree: primary leaf-blades
rarely over 5 mm. wide: second
glume shorter than fruit and
Autumnal form topheavy-reclin-
ing: primary leaf-blades 6-10
mm. wide: second glume equal-
ling fruit and sterile lemma.
Panicle narrow, one-fourth to one-third as wide as long.
Panicle open, two-thirds as wide as long, or more.
Spikelets 1.5 mm. long.
Spikelets 1.3 mm. long or less.
Stem and leaf-sheaths glabrous.
47. P. Bicknellii.
48. P. nudicaule.
49. P. microcarpon.
60. P. barbulatum.
50. P. annulum.
51. P. nitidum.
52. P. mattamuskeetense.
53. P. Clutei.
53. P. Clutei.
54. P. lucidum.
55. P. sphagnicola.
54. P. lucidum.
55. P. sphagnicola.
56. P. caerulescens.
57. P. roanokense.
58. P. yadkinense.
59. P. dichotomum.
60. P. barbulatum.
61. P. spretum.
62. P. Lindheimeri.
63. P. longiligulatum.
Stem and leaf-sheaths appressed-pubescent.
Spikelets 1.2-1.3 mm. long.
Spikelets not over 1 mm. long.
Spikelets not over 2 mm. long.
Plant grayish, velvety-pubescent.
Spikelets 1.4-1.5 mm. long: autumnal leaf-blades
involute-pointed (see also P. albemarlense).
Spikelets 1.8-2 mm. long: autumnal leaf- blades
Plant dark-green or olive-green when dry:
spikelets 1.9-2 mm. long.
Plant light-green or yellow-green when dry.
Plant pubescent, often villous, but not velvety.
Vernal leaf-blades glabrous or nearly so on the
upper surface, firm in texture.
Vernal leaf-blades pubescent on upper surface,
sometimes pilose near base and margins
Spikelets 1.3-1.5 mm. long: vernal leaf-blades
long-pilose on upper surface.
Autumnal form widely decumbent-spread-
ing, forming a mat: vernal stems soon
geniculate-spreading: plants olivaceous.
Autumnal form erect or leaning, never
forming a mat: plants yellowish-green.
Spikelets 1.6-2 mm. long: vernal leaf-blades
pilose or pubescent.
Spikelets 2.2 mm. or more long: plants conspicuously
Spikelets 2.2-2.4 mm. long.
Pubescence on stems and leaf-sheaths horizontally
spreading: autumnal form freely branching.
Pubescence on stems and leaf-blades appressed or
ascending: autumnal form rather sparingly
Spikelets 2.7-2.9 mm. long.
Spikelets 2-3.2 mm. long, mostly elliptic.
Winter leaf-blades 5-10 cm. long: spikelets 2 mm.
long: plants blue-green.
Winter leaf-blades 1-3 cm. long.
Spikelets 3.2 mm. long: first glume conspicuously
Spikelets not over 2.5 mm. long: first glume not
Spikelets about 2.4 mm. (2.2-2.4 mm.) long:
panicle open; branches stiffly spreading.
Spikelets 2-2.1 mm. long: panicle rather
dense; branches ascending.
Spikelets not over 1.9 mm. long, obovate, turgid.
Spikelets about 1.9 mm. long.
Spikelets about 1.5 mm. long.
Stem spreading: leaf-blades obscurely nerved: panicle
nearly as broad as long.
Stem erect or ascending: leaf-blades rather strongly
nerved: panicle never more than two-thirds as
broad as long, usually less.
Spikelets 1.5-1.6 mm. long: leaf-blades lanceolate,
the upper not reduced.
Spikelets 1-1.2 mm. long: leaf-blades tapering from
base to apex, the upper much smaller than the
Ligule about 1 mm. long: sheaths or some of them
Ligules obsolete or nearly so: pubescence if present not
Leaf-blades prominently white-margined, firm: spike-
lets densely puberulent.
64. P. leucothrix.
65. P. Wrightianum.
66. P. auburn.
67. P. Thurowii.
68. P. lanuginosum.
69. P. tennesseense.
70. P. albemarlense.
71. P. meridionale.
72. P. Huachucae.
73. P. villosissimum.
74. P. pseudopubescens.
75: P. ovale.
76. P. wilmingtonense.
77. P. malacon.
81. P. sphaerocarpon.
82. P. polyanthes.
83. P. erectifolium.
84. P. curtifolium.
Leaf-blades puberulent beneath, often above:
sheaths and sometimes lower internodes as-
Leaf-blades glabrous: sheaths glabrous or minu-
tely ciliate only.
Uppermost leaf-blades much reduced: stems
branching from lower nodes only, the
branches repeatedly branching.
Uppermost leaf-blades about as long as the
others: stems bearing short branches from
the upper and middle nodes.
Leaf-blades not white-margined or very obscurely so
(or if white margin is evident spikelets only
1.1 mm. long) : spikelets glabrous or puberu-
Stem branching only at base: plants soft, light
Stem branching at the nodes: plant firm or at
least not soft.
Spikelets 1.1-1.2 mm. long: leaf-blades
rarely as much as 5 cm. long.
Spikelets 1.2-1.5 mm. long.
Leaf-blades elongate, at least some of
them 8-10 cm. long.
Leaf-blades not over 3 cm. long.
Spikelets 1.1 mm. long: winter leaf-blades
bluish-green, not glossy.
Spikelets 1.3-1.5 mm. long.
Leaf-blades involute, falcate, with long
stiff hairs on margin near base:
plants stiff and wiry.
Leaf-blades not involute, or at tip
only, not falcate: plants bright-
green: winter leaf-blades conspicu-
ous, glossy green.
Spikelets 1.5-1.6 mm. long.
Spikelets 2 mm. or more long.
Leaf-blades, or some of them, at least 8 mm. wide,
glabrous on the upper surface: fruit papillose-
Leaf-blades not over 6 mm. wide (or if wider, pu-
berulent on the upper surface) : fruit smooth
Spikelets 2.4-2.6 mm. long: leaf-blades narrowed
toward the base.
Spikelets not over 2.1 mm. long.
Leaf-blades firm, glabrous above: stem stiffly
Leaf-blades lax, softly puberulent on both
surfaces: stem decumbent.
Nodes bearded: blades velvety-pubescent beneath.
Plants lax, soft-velvety throughout: spikelets not
over 3 mm. long.
Plants stiff, pubescence harsh: spikelets about 4 mm.
Nodes not bearded : leaf-blades not velvety.
Spikelets narrowly obovate, subacute: plants oliva-
Spikelets broadly obovate, turgid, blunt: plants green,
pubescence, if any, not appressed.
Pubescence soft-villous or velvety: spikelets abruptly
Pubescence when present not velvety.
Spikelets elliptic: fruit about 2.5 mm. long.
Spikelets ovate, that is, broadest below the middle:
fruit 2 mm. long or less.
85. P. tenue.
86. P. albomarginatum.
87. P. trifolium.
88. P. vernale.
89. P. chamaelonche.
90. P. glabrifolium.
91. P. cnsifoliuim.
92. P. concinnius.
93. P. breve.
94. P. flavovirens.
95. P. portoricense.
96. P. Tebberianum.
97. P. patentifolium.
98. P. lancearium.
99. P. patulum.
100. P. malacophyllum.
101. P. Ravenelii.
102. P. oligosanthes.
103. P. Scribnerianum.
104. P. scoparium.
105. P. aculeatum.
Leaf-sheaths or some of them hispid, rarely gla-
brous: autumnal phase with crowded branch-
Leaf-sheaths glabrous : autumnal phase sparingly
Plant glaucous, glabrous: basal leaf-blades conspicu-
ously ciliate: vernal stems usually solitary.
Plant not glaucous.
Leaf-blades linear: first glume about half as long as
Stems crisp-puberulent: leaf-blades usually rigid,
symmetrical, rarely over 10 mm. wide: spike-
lets about 2.5 mm. long.
Stems glabrous or softly puberulent: leaf-blades
firm or lax: spikelets 2.7-3.2 mm. long.
Stems erect, or autumnal form leaning: leaf-
blades symmetric, broadly cordate.
Stems decumbent: leaf-blades usually unsym-
metric and falcate, narrowed to the scarcpy.y
Leaf-sheaths, at least the lower and those of the
branches, strongly papillose-hispid.
Leaf-sheaths glabrous or softly villous.
Nodes glabrous : spikelets 3.4-3.7 mm. long.
Nodes bearded: spikelets 4-4.5 mm. long.
Plant vigorous, extensively rooting, with erect narrow,
often elongate, panicles and acute spikelets.
Plant stout, extensively creeping, with spreading pan-
icles and long narrowly pointed spikelets.
1. P. Chapmani Vasey. Stem ascending or
spreading, 40-100 cm. tall: leaf-blades erect,
2-5 mm. wide: panicle elongate, as much as
30 cm. long, the branches remote, appressed.
-Rocky pinelands, shell-mounds and cleared
hammock land, S pen. Fla. and the Keys.-
106. P. scabriusculum.
107. P. cryptanthum.
108. P. mutabile.
109. P. equilaterale.
110. P. Ashei.
111. P. commutatum.
112. P. Joorii.
113. P. clandestinum.
114. P. latifolium.
115. P. Boscii.
116. P. hemitomon.
117. P. gymnocarpon.
2. P. barbinode Trin. Stem erect from a f i
long decumbent rooting stoloniferous base,
200-600 cm. long: leaf-sheaths villous, or
glabrous toward the summit, densely pubes-
cent on the collar: blades 10-15 mm. wide,
glabrous: panicle 12-20 cm. long, the rather
distant subracemose densely flowered branches ascending or spreading: spike-
lets 3 mm. long. [P. molle (Fl. SE. U. S.]-Hammocks, fields, and waste-
places, Coastal Plain, Fla. to Tex.-(W. I., Mex., C. A., S. A., 0. W.)
3. P. paludivagum H. & C. Stem elongate, as much as 200 cm. long, the base
creeping, rooting at the nodes: panicle 25-35 cm. long; racemes 12-15, erect,
the lower distant, 3 cm. long.-In fresh water, Coastal Plain, Fla. and Tex.-
(Mex., C. A., S. A.)
4. P. geminatum Forsk. Stem 25-80 cm. tall, spreading from a somewhat
decumbent base: panicle 12-30 cm. long, the racemes 12-18, erect, the lower
2.5-3 cm. long. [P. paspaloides (Fl. SE. U. S.) ]-(WATER-GRASS.)-Moist
ground, ponds and prairies, Coastal Plain, 6 Fla. and Tex.-(W. I., Mex., C. A.,
S. A., 0. TW.)-Plant cespitose.
5. P. fasciculatum Swartz. Stem erect or spreading from a decumbent base,
30-100 cm. tall: leaf-sheaths glabrous or papillose-hispid: blades 6-20 mm.
wide, glabrous: panicle 5-15 cm. long, the branches racemose along the main
axis, solitary or clustered, 5-10 cm. long, spreading, the spikelets short-
pedicelled panicless smaller and more compact, the branches appressed: leaf-
blades narrower, pubescent: spikelets 2.5-3 mm. long, in P. fasciculatum
reticulatum. Tex. to Ariz.; introd. into S. C.-(Mex., C. A., S. A.)): spikelets
mostly brownish, usually 2-2.5 mm. long, glabrous. [P.- fscum Swartz]-
Hammocks, fields, and waste-places, S Fla. and S Tex.-(W. I., Mex., C. A.,
6. P. reptans L. Stem prostrate or decumbent at base, rooting at the lower
nodes, the ascending portion 10-30 cm. tall: leaves glabrous, the blades ciliate
at base: panicle 2-6 cm. long, the 3-12 spike-like branches ascending or spread-
ing: first glume truncate, about one-sixth the length of the spikelet. [P. pros-
tratum Lam.]-Fields and moist open ground, Coastal Plain, Fla. to Tex.-
-(W. I., Mex., C. A., S. A.)
7. P. adspersum Trin. Stem ascending or spreading from a decumbent base,
30-100 cm. tall: leaf-blades 6-20 cm. wide: panicle 6-15 cm. long, the few
ascending spike-like racemes 3-10 cm. long: spikelets pale, 3.5-4 mm. long,
abruptly acuminate, more or less hispid.-Moist open ground, Fla.-(W. I.)-
A robust form is P. keyense Mez.
8. P. texanum Buckl. Stem stout, 50-150 cm. tall, branching at base and
lower nodes, pubescent below nodes and panicle: leaf-sheaths and blades softly
pubescent: panicle 8-20 cm. long, 1-3 cm. wide, the axis densely pubescent:
spikelets fusiform, pointed, pilose. Prairies and open ground, Coastal Plain,
Tex. and Okla., introd. in Ariz., and eastward to Fla. and N. C.-(Mex.)
9. P. bartowense Scribn. & Merr. Stem erect, as much as 200 cm. tall: leaf-
blades 15-40 cm. long, 5-13 mm. wide: glabrous or nearly so: panicle large,
loosely spreading, 15-60 cm. long: spikelets short-pediceled, appressed, about
2.5 mm. long.-(WITCH-GRASS.)-Low grounds, marshes, and prairies, Fla.
10. P. dichotomiflorum Michx. Stem much-branched, ascending from a genicu-
late base, usually 50-100 cm. tall, sometimes as much as 2 m., the plant usually
glabrous throughout: leaf-blades 3-20 mm. wide: panicles terminal and axillary,
10-40 cm. long: spikelets short-pediceled along the main. branches, usually 2.5
mm. long. [P. proliferum (Fl. SE. U. S.)]-Low grounds, fields, roadsides,
and waste-places, various provinces, Fla. to Tex., Calif., Nebr., and Me.-
11. P. miliaceum L. Stem as much as 100 cm. tall, rather stout: leaf-blades
mostly pilose, as much as 30 cm. long and 2 cm. wide: panicle 10-30 cm. long,
usually rather compact, the numerous branches narrowly ascending, spikelet-
bearing toward the summit.-Roadsides, waste-places, and cult. grounds, occa-
sional throughout the U. S., rare S-Cult. as PRoso. HOG-MILLET. BROOM-CORN
MILLET. Nat. of Eu.-(Mex.)
12. P. flexile (Gatt.) Scribn. Stem erect, 20-70 cm. tall, slender, branching
at base: leaf-blades erect, glabrous to sparsely hispid, 2-6 mm. wide: spikelets
3-3.5 mm. long, acuminate.-Sandy damp soil, various provinces, Fla. to Tex.,
S. D., and Ont.
13. P. capillare L. Stem erect or ascending, simple or sparingly branched,
20-80 cm. tall: leaf-blades 5-15 mm. wide, hispid: panicle large, diffuse, at
maturity breaking away as a tumble-weed: spikelets 2-2.5 mm. long.-(WITCH-
GRASS.)-Woods, fields, marshes, prairies, and waste-places, various provinces,
Fla. to Tex., Mont., and Me.-Panicum Bergii Arech., differing from P.
capillare in being perennial, in having involute leaf-blades, the axils of the
panicle strongly pilose, and the lower branches in verticils, has been found on
ballast at Mobile, Ala., and Galveston, Tex.
14. P. Gattingeri Nash. Stem soon decumbent-spreading, rooting at the lower
nodes, as much as 100 cm. long: leaf-blades 6-10 mm. wide, more or less hispid:
panicles numerous, terminal and axillary, the former 10-15 cm. long, the latter
smaller.-Open ground, dry hills, woods, cult. grounds, and waste-places, various
provinces, N. C. and Tenn. to Minn and N. Y.
15. P. philadelphicum Bernh. Stem mostly erect, 15-20 cm. tall, usually zigzag
at the slender base: leaf-blades 2-6 mm. wide, sparingly hirsute: panicle ovoid,
few-flowered, the spikelets usually in twos at the ends of the branchlets.-Dry
open ground, hillsides, barrens, and roadsides, various provinces, Ga. to Okla.,
Wis., and Me.
16. P. maximum Jacq. Stem erect, 100-250 cm. tall, from a creeping root-
stock: leaf-sheaths papillose-hirsute to glabrous: ligules 4-6 mm. long: blades
elongate, 1-3.5 cm. wide: panicle 20-50 cm. long, about one-third as wide, the
branches ascending, the lower in whorls, pilose in the axils: spikelets about 3
mm. long.-(GUINEA-GRASS.)-Cult. grounds, roadsides, and ditches, Coastal
Plain, Fla. Nat. of Afr.-(W. I., Mex., C. A., S. A., 0. W.)
17. P. repens L. Stem rigid, 30-80 cm. tall, from an extensively creeping root-
stock: leaf-blades 2-5 mm. wide: panicle 7-12 cm. long, the branches ascending:
spikelets pale, about 2.5 mm. long.-Sea beaches, sand-dunes, and sandy soil,
Coastal Plain, Ala. to La. Nat. of O. W.-(W. I., G. A., S. A.)
18. P. Gouini Fourn. Resembling P. repens, usually lower: panicle smaller,
narrower, more densely flowered, commonly purple: spikelets 2-2.4 mm. long.
[P. halophilum Nash]-Sea beaches, Ala. and Miss.--(Mex.)
19.. P. amarun Ell. Plant glaucous and glabrous throughout: stem solitary
from a stout extensively creeping rootstock, 30-100 cm. tall: panicle not over
3 cm. wide, few-flowered, the branches appressed: spikelets 5-6.5 mm. long,
acuminate, strongly nerved. [P. amaroides Scribn. & Merr.]-Beaches and
dunes, Coastal Plain and New England Coast, Ga. to Miss. and Conn.
20. P. amarulum H. & C. Resembling P. amarum, but grows in large bunches,
100-200 cm. tall: panicles 5-10 cm. wide, nodding: spikelets 4.5-5.5 mm. long.
[P. amarum (Fl. SE. U. S.)]-(BEACH-GRASS.)-Beaches and dunes, Coastal
Plain, Fla. to La. and Va.-(W. I.)
21. P. virgatum L. Plant erect, with stout scaly rootstocks, glabrous through-
out, or upper surface of leaf-blades pilose, 100-200 cm. tall (more slender, the
panicle narrower: spikelets 2.8-3.2 mm. long, first glume about half the length
of the spikelet, acute only, in P. virgatum cubense. [P. virgatum breviramosum
Nash]-Sandy moist woods, Coastal Plain, Fla. to Miss. and Conn. (W. I.)):
panicles 15-50 cm. long, open or diffuse: spikelets 3.5-5 mm. long, acuminate.-
Prairies, pinelands, marshes, hammocks, and salt marshes, various provinces,
Fla. to Ariz., Wyo., and Me.-(Mex., C. A., S. A.)
22. P. tenerum Beyr. Plant slender in small tufts from a knotted crown,
40-90 cm. tall: leaf-blades erect, firm, 2-4 mm. wide: panicle 3-8 cm. long,
about 5 mm. wide: spikelets about 2.5 mm. long. [P. stenodes (Fl. SE. U. S.)]
-Wet pinelands, ponds, and prairies, Coastal Plain, Fla. to Tex. and N. C.-
23. P. anceps Michx. Stem erect, rather stout, 50-100 cm. tall: leaf-sheaths
glabrous to papillose-pilose: blades 20-50 cm. long, 4-12 mm. wide, pilose above
toward the base: panicle 15-40 cm. long, the remote branches somewhat
spreading: spikelets somewhat curved, set obliquely on the pedicels. [P. ros-
tratum Muhl.]-Moist sandy soil, stream-banks, meadows, and pinelanids, various
provinces, Fla. to Tex., Kans., and N. J.
24. P. rhizomatum H. & C. Resembling P. anceps, the stem more slender:
rootstocks more numerous: leaves shorter, somewhat crowded at the base, the
sheaths villous.-Moist sandy woods, pinelands and swamps, Coastal Plain, Fla.
to Tex. and Va.
25. P. longifolium Torr. Plant in dense tufts, 35-80 cm. tall, usually sur-
rounded by basal leaves: leaf-sheaths usually glabrous, sometimes villous to-
ward the summit: blades 2-5 mm. wide: panicle 10-25 cm. long: spikelets
about 2.5 mm. long: first glume not over half the length of the spikelet. [P.
pseudanceps Nash]-Moist acid sandy soil and low pinelands, Coastal Plain
and New England Coast, Fla. to Tex. and R. I.
26. P. Combsii Scribn. & Ball. Resembling P. longifolium, but usually glab-
rous, the leaf-blades shorter: lateral panicles seldom developed: spikelets 3-3.5
mm. long, the first glume two-thirds to three fourths as long as the spikelet.-
Wet woods, low pinelands, and cypress-ponds, Coastal Plain, Fla. to La. and Ga.
27. P. stipitatum Nash. Resembling P. agrostoides, often purple-tinged
throughout, the stem strongly compressed: panicles usually several to a stem,
10-20 cm. long, rather narrow.-Moist soil, and stream-banks, various pro-
vinces, S. C. to Tex., Mo., and Conn.
28. P. agrostoides Spreng. Plant 50-100 cm. tall, with a .dense clump of
stems from a short caudex, with numerous shoots of short leaves at the base:
stems compressed: panicle 10-30 cm. long, the stiff branches ascending or
spreading: spikelets about 2 mm. long.-Wet ipeadows, ponds, swamps and
marshes, various provinces, Fla. to Tex., Kans., ,nd Me.
29. P. condensum Nash. Resembles P. agrostoides, usually rather taller:
panicle 10-25'cm. long, rarely over 5 cm. wide, rather compact: spikelets 2.2-
2.5 mm. long, turgid, the tips slightly spreading.-Wet places, marshes, swamps
and ditches, Coastal Plain and rarely adj. provinces, Fla. to Tex. and Pa.
30. P. hians Ell. Stem slender, erect or geniculate and rooting at the lower
nodes, 20-60 cm. long: leaf-blades 1-5 mm. wide: panicle 5-20 cm. long,
usually loose and open, the primary branches few, slender, distant, spreading
to drooping, the spikelets towards the ends: spikelets about 2.3 mm. long,
rather strongly nerved, glabrous. [Steinchisma hians Nash]-Damp soil, low
woods, stream-banks, pools, and ditches, Coastal Plain and adj. provinces, Fla.
to N. M. and N. C.
31. P. verrucosum Muhl. Plant bright-green, lax, soon decumbent, widely
spreading, and divaricate-branched, as much as 150 cm. long: leaf-blades thin,
lax, 4-10 mm. wide: panicle 5-30 cm. long, diffuse, the mostly solitary branches
bearing a few short-pedicelled spikelets mostly in 2's toward the ends.-Wet
shady places, acid swamps, ditches, and woods, Coastal Plain and New England
Coast, Fla. to Tex. and Mass., and Great Lake Lowlands, N Ind.
32. P. depauperatum Muhl. Stem 20-40 cm. tall, erect and rather stiff: leaf-
sheaths glabrous or pilose: blades linear, 6-15 cm. long, 2-5 mm. wide, often
involute in drying: panicle 4-8 cm. long, the rather strict remote branches
ascending: spikelets glabrous or sparsely pubescent. Autumnal phase similar,
but with reduced secondary panicles more or less concealed among the basal
leaves.-Open sterile woods, fields, and rocky slopes, various provinces, Ga. to
Tex., Minn., and Me.
33. P. linearifolium Scribn. Stem 20-45 cm. tall, not stiff: leaf-sheaths
papillose-pilose: blades 10-35 cm. long, 2-4 mm. wide: panicle 5-10 cm. long.
Autumnal phase with small panicles among the basal leaves.-Dry woods, hill-
sides, fields and thickets, various provinces, Ga. to Tex., Minn. and Me.
34. P. laxiflorum Lam. Stem slender, 20-60 cm. tall, erect, or geniculate at
base: leaf-blades 10-18 cm. long, 7-12 mm. wide: panicle 8-12 cm. long, lax,
few-flowered, the branches flexuous, spreading, the lower often deflexed. Au-
tumnal phase much-branched at base, forming a soft spreading mat, with
small secondary panicles intermixed. [P. pyriforme Nash] Rich woods,
Coastal Plain, Fla., Ga., and Ala.
35. P. xalapense H. B. K. Resembling P. laxiflorum; differing in the pilose
and ciliate leaf-blades and somewhat smaller (2 mm.) spikelets (with ovoid
more compact panicles and somewhat smaller spikelets, about 1.7 mm. long,
in P. xalapense strictirameum. S. C. to La.) [P. laxiflorum (Fl. SE. U. S.)]
Open woods, pinelands, hammocks, and rocky fields, various provinces, Fla. to
Tex., Mo., and Md. (W. I., Mex.)
36. P. ciliatum Ell. Stem 5-30 cm. tall, erect or spreading: leaf-blades 3-6
cm. long, 3-8 mm. wide, conspicuously ciliate: panicle 3-4 cm. long, the axis
pilose. Autumnal phase a soft flat mat. Low pinelands, Coastal Plain, Fla.
to La. and N. C.
37. P. polycaulon Nash. Resembling P. ciliatum: panicle larger, the axis
sparsely pilose: spikelets about 1.5 mm. long, rarely as much as 2 mm. long.
Low pinelands, and prairies, Coastal Plain, Fla. to Miss. (W. I.)
38. P. strigosum Muhl. Resembling P. ciliatum: panicle-axis and branches
pilose: spikelets 1.3-1.5 mm. long. Sandy woods and pinelands, Coastal Plain,
Fla. to La., Tenn., and Va. (W. I., Mex.)
39. P. chrysopsidifolium Nash. Stems ascending or spreading, 30-45 cm.
tall: leaf-blades 5-10 cm. long, 3-5 mm. wide, conspicuously pointed, villous
on both surfaces: panicles 4-6 cm. long, the flexuous branches ascending or
spreading: spikelets villous. Autumnal phase forming mats, the blades 1-3
cm. long, 1.5 mm. wide, papery.-Sandy pinelands and woods, Coastal. Plain,
Fla. to La.-(W. I.)
40. P. consanguineum Kunth. Stem ascending or spreading, 20-55 cm. tall,
densely felty-villous below: leaf-blades erect, 7-11 cm. long, 5-8 mm. wide:
panicles 4-8 cm. long, the lower branches narrowly ascending. Autumnal
phase spreading or decumbent, the numerous branches somewhat flabellately
fascicled, the blades 3-4 cm. long, 2-3 mm. wide.-Sandy pinelands and
meadows, Coastal Plain, Fla. to Tex. and Va.
41. P. angustifolium Ell. Stem erect, 30-55 cm. tall, the lowermost inter-
nodes gray crisp-villous, the upper glabrous: panicle 4-12 cm. long: spikelets
2.5-2.8 mm. long, papillose-villous. Autumnal phase stiffly ascending or some-
what topheavy-reclining, not mat-like: blades very numerous.-Sandyi woods
and pinelands, Coastal Plain and adj. provinces, Fla. to Tex. and Pa.
42. P. fusiforme A. Hitchc. Vernal phase similar to that of P. angusti-
folium: stem 30-70 cm. tall: lower leaf-blades softly pubescent beneath:
panicle long-exserted. Autumnal phase erect or reclining, forming dense
bushy clusters 30-60 cm. tall.-Sandy pinelands and prairies, Coastal Plain,
Fla. to Miss. and Ga.-(W. I.)
43. P. neuranthum Griseb. Stem stiff, 30-60 cm.: leaf-blades erect or ascend-
ing, 3-5 mm. wide: panicles 5-9 cm. long: spikelets 2 mm. long, finely papil-
lose-pubescent. Autumnal phase slender.-Prairies, open woods and pine-
lands, Coastal Plain, Fla. to Miss.-(W. I.)
44. P. ovinum Scribn. & Smith. Stem erect, 30-50 cm. tall: leaf-blades erect
or ascending, the lowermost as much as 1 cm. wide: panicle 5-9 cm. long,
three-fourths as wide: spikelets slightly over 2 mm. long, minutely papillose-
pubescent. Autumnal leaf-blades not much reduced.-Dry or moist grounds,
woods and pinelands, Coastal Plain, Miss. to Tex. and Ark.-(Mex.)
45. P. arenicoloides Ashe. Stem mostly erect, 30-50 cm. tall: leaf-blades
3-4 mm. wide: panicle 4-6 cm. long: spikelets papillose-pubescent. Autumnal
phase bushy-branched, erect or topheavy.-Sandy pinelands, sand-dunes, and
woods, Coastal Plain, Fla. to Tex. and N. C.-(W. I., C. A.)
46. P. aciculare Desv. Stem ascending, 20-50 cm. tall: leaf-blades stiff,
spreading or ascending, narrowed to an involute point, 2-5 mm. wide: panicle
open, 3-7 cm. long, the flexuous branches spreading. Autumnal phase bushy-
branched, 10-30 cm. long, spreading and forming dense cushions, the blades
1-3 cm. long. [P. arenicola Ashe]-Sandy woods and pinelands, Coastal
Plain, Fla. to Tex., Okla., and N. J.-(W. I.)
47. P. Bicknellii Nash. Stem erect, 30-50 cm. tall, glabrous, or puberulent
toward base: nodes sparsely bearded or glabrous: leaf-sheaths glabrous or
nearly so: blades stiffly ascending, 8-15 cm. long, 3-8 mm. wide, the upper-
most usually longest: panicle ovoid, 5-8 cm. long, the branches ascending:
spikelets 2.3-2.8 mm. long, sparsely pubescent, rarely glabrous. Autumnal
phase erect, branching from middle nodes, forming a loose bushy crown of
stiffly ascending blades. [P. nemopanthum Ashe]-Dry sterile or acid woods
and hillsides, various provinces N of Coastal Plain, Ga. to Mo. and Conn.
48. P. nudicaule Vasey. Stem erect from a spreading base, 40-60 cm. tall,
glabrous: panicle long-exserted, 4-7 cm. long.-Swamps, Coastal Plain, W Fla.
and S Ala.
49. P. microcarpon Muhl. Stem erect, or geniculate at base, usually 60-100
cm. tall: leaf-sheaths glabrous or the lowermost pubescent: blades 8-15 mm.
wide: panicle 8-12 cm. long, the branches ascending. Autumnal phase re-
peatedly branching from all the nodes, reclining from the weight of the dense
mass: leaf-blades and panicles reduced. [P. barbulatum (Fl. SE. U. S.)]-
Wet woods, marshy places, swamps, hillsides, and thickets, various provinces,
Fla. to Tex., Mo., and Mass.
50. P. annulum Ashe. Stem usually purplish, 35-60 cm. tall: leaf-sheaths
velvety or the upper nearly glabrous: blades 7-13 mm. wide: panicle 6-8 cm.
long: spikelets 2 mm. long. Autumnal phase erect, bearing a few erect
branches at the upper nodes.-Dry woods, Piedmont and rarely inner margin
of Coastal Plain, Ga. to Miss. and N. J.
51. P. nitidum Lam. Stem erect, 30-60 cm. tall, sometimes taller: leaf-
sheaths glabrous, or the lower pubescent, mottled or glandular: blades 5-10
mm. wide, glabrous: panicle 5-8 cm. long, the axis and the ascending branches
viscid-spotted. Autumnal phase erect or reclining from the weight of the
foliage, the branchlets forming large clusters from the nodes: reduced blades
numerous, 1-3 cm. long, 1-3 mm. wide, flat or soon involute.-Low moist
ground, pinelands, prairies, and hammocks, Coastal Plain, Fla. to Tex. and
52. P. mattamuskeetense Ashe. Stem erect, usually purplish, 40-100 cm.
tall: leaf-blades 8-12 cm. long, 8-12 mm. wide, glabrous or velvety: panicle
8-10 cm. long, the flexuous branches spreading: spikelets about 2.5 mm. long.
Autumnal phase erect or decumbent, branching rather sparingly from the mid-
dle nodes.-Low moist grounds, Coastal Plain, N. C. to N. Y.
53. P. Clutei Nash. Resembling P. mattamuskeetense, but more nearly gla-
brous, only the lowermost nodes, leaf-sheaths and blades velvety: spikelets
slightly smaller.-Moist acid soils, Coastal Plain and New England Coast, N. C.
54. P. lucidum Ashe. Plant glabrous, at first erect and resembling those of
P. dichotomum, the weak stem soon decumbent: spikelets 2 mm. long, glabrous
or rarely pubescent. Autumnal phase repeatedly branching, forming large
clumps or mats of slender, weak vine-like stems, the branches elongate and
divergent, not fascicled.-Wet woods, prairies, and sphagnum bogs, Coastal
Plain and New England Coast, Fla. to Tex. and Mass., and Great Lake Low-
land, N Ind.-(W. I.)
55. P. sphagnicola Nash. Plant glabrous: stem slender, erect or reclining,
50-100 cm. tall: spikelets 2.5 mm. long, glabrous or puberulent toward the
apex. Autumnal phase decumbent or finally prostrate-spreading, divaricately
branched from all the nodes.-Edges of cypress swamps and in sphagnum
bogs, Coastal Plain, Fla. and Ga.
56. P. caerulescens Hack. Plant glabrous: stem slender, 50-75 cm. tall: leaf-
blades 5-8 cm. long, 4-7 mm. wide, usually purplish-beneath: panicle 3-7 cm.
long: spikelets turgid, strongly nerved.-Marshes, prairies, and swampy woods,
Coastal Plain, Fla. to Miss. and N. J.-(TV. I.)
57. P. roanokense Ashe. Resembles P. caerulescens: stem 50-100 cm. tall:
panicle more spreading: spikelets turgid, strongly nerved, purple-tinged at
base. [P. curtivagim~n Ashe]-Open swampy woods, Coastal Plain, Fla. to
Tex. and Va.-(W. I.)
58. P. yadkinense Ashe. Plant glabrous, in a small tuft: stems erect and
as much as 100 cm. tall: leaf-blades 8-11 mm. wide: panicle 10-12 cm. long:
spikelets about 2.5 mm. long, the second glume and sterile lemma pointed
beyond the fruit. Autumnal phase erect or leaning, loosely branched from
the middle nodes.-Moist woods and swamps, Coastal Plain and rarely adj.
provinces, Ga. to La., Ill., and Pa.-(Mex.)
59. P. dichotomum L. Plant glabrous: stem erect from a knotted crown,
30-50 cm. tall: leaf-blades spreading, 5-11 cm. long, 4-6 mm. wide: panicle
4-9 cm. long: spikelets 2 mm. long, glabrous, rarely pubescent.-Dry sterile
woods, various provinces, Fla. to Tex., Mich., and N. B.
60. P. barbulatum Michx. Resembling P. dichotomum: differs in having
pubescent lower nodes and in the diffusely branched autumnal phase, forming
large reclining bunches, the slender branches recurved, the numerous flat leaf-
blades horizontally spreading.--Sterile woods, pinelands, and fields, various
provinces, Ga. to Tex., Mich., and Mass.
61. P. spretum Schult. Plant glabrous: stem erect, 30-90 cm. tall: panicle
8-12 cm. long, the branches ascending or appressed: spikelets about 1.5 mm.
long, pubescent or rarely glabrous. Autumnal phase reclining, the branches
in short fascicles at the nodes, the blades much reduced. [P. octonodum J. G.
Smith P. paucipilum Nash P. nitidum (Fl. SE. U. S.) ]-Wet acid soil and low
pinelands, Coastal Plain and New England Coast, Fla. to Tex. and Me., and
Great Lake Lowland, N Ind.
62. P. Lindheimeri Nash. Stem stiffly ascending or spreading, 30-100 cm.
tall: nodes swollen: leaf-sheaths glabrous or the lower pubescent: blades 5-10
cm. long, 6-8 mm. wide, usually glabrous. Autumnal phase usually stiffly
spreading or radiate-prostrate, the internodes elongate, with tufts of short
appressed branches at the nodes, the blades reduced, involute-pointed, often
conspicuously ciliate at base.-Dry woods, open grounds, and prairies, various
provinces, Fla. to N. M., Calif., Minn., and Me.
63. P. longiligulatum Nash. Stem relatively stout, 30-70 cm. tall: nodes
swollen: leaf-blades rather firm and thick, 4-8 cm. long, 4-8 mm. wide, gla-
brous above, puberulent beneath: panicle 3-8 cm. long: spikelets 1.1-1.2 mm.
long, pubescent. Autumnal phase reclining, the branchlets crowded on spread-
ing branches, the blades reduced and subinvolute.-Low pinelands, swamps,
and ponds, Coastal Plain, Fla. to La. and N. C.
64. P. leucothrix Nash. Stem erect or ascending, 25-45 cm. tall, appressed
papillose-pilose: leaf-blades rather firm, 3-7 cm. long, 3-7 mm. wide, glabrous
above, puberulent beneath: panicle 3-8 cm. long. Autumnal phase with ap-
pressed fascicled branches: the blades not much reduced. [P. parvispiculum
Nash]-Low pinelands and cypress swamps, often in acid peat, Coastal Plain,
Fla. to La. and N. J.--(W. I.)
65. P. Wrightianum Scribn. Stem weak and slender, ascending from a de-
cumbent base, 15-40 cm. tall, minutely pubescent: leaf-blades 2-4 cm. long,
3-5 mm. wide, glabrous or puberulent beneath, minutely pilose above: panicle
3-6 cm. long. Autumnal phase decumbent spreading, somewhat bushy-
branched.-Moist soil, swamps, ponds, and cypress-heads, Coastal Plain and
New England Coast, Fla. to Tex. and Mass.-(W. I.)
66. P. auburne Ashe. Stem 20-50 cm. tall, geniculate, widely spreading,
densely papillose, silky-villous below, velvety with copious silky hairs inter-
mixed above: leaf-sheaths villous: blades 3-7 cm. long, 3-5 mm. wide: panicle
3-5 cm. long. Autumnal phase diffusely branched, prostrate spreading, form-
ing large mats, the branches curved upward at the ends.-Sandy woods, Coastal
Plain, Fla. to La., Ark., and N. Y.-Plants tufted.
67. P. Thurowii Scribn. & Smith. Stem erect, 35-70 cm. tall, the nodes
bearded: leaf-blades rather stiff, 7-12 cm. long, 6-10 mm. wide, velvety be-
neath: panicle 7-11 cm. long. Autumnal phase erect, bearing at the middle
nodes a few appressed fascicled branches.-Prairies and dry open woods,
Coastal Plain, Ala. to Tex.
68. P. lanuginosum Ell. Stem 40-70 cm. tall, spreading, the nodes villous,
usually with a glabrous ring below: panicle 6-12 cm. long, the axis pubescent,
the lower branches often drooping. Autumnal phase widely spreading or de-
cumbent, freely branching. [P. ciliosum Nash]-Moist sandy woods, thickets
and pinelands, mostly near the coast, Coastal Plain, Fla. to Tex. and N. J.
69. P. tennesseense Ashe. Plant somewhat bluish-green: stem erect or stiffly
spreading, 25-60 cm. tall: leaf-sheaths spreading-pubescent: blades with a
thin white cartilaginous margin, ascending or erect, 5-8 mm. long, the lower
surface appressed-pubescent: panicle 4-7 cm. long: spikelets about 1.6 mm.
long. Autumnal phase widely spreading, with numerous fascicled branches,
often forming prostrate mats.-Open moist ground, woods, and barrens, various
provinces, Ga. to Ariz., Minn., and Me.-(Mex.)
70. P. albemarlense Ashe. Plant grayish-villous: stem 25-45 cm. tall: leaf-
blades puberulent as well as long-villous on the upper surface: panicle 3-5 cm.
long, the axis puberulent: spikelets 1.4 mm. long. Autumnal phase freely
branching.-Low sandy woods and dunes, Coastal Plain and New England
Coast N. C. to Minn. and Mass. and Great Lake Lowland, N Ind.
71. P. meridionale Ashe. Stem very slender, 15-40 cm. tall: panicle 1.5-4
cm. long, the axis appressed-pubescent: spikelets about 1.3 mm. long. Au-
tumnal phase erect or nearly so, not bushy. [P. filiculme Ashe]-Sandy soil,
sterile woods, and bogs, various provinces, Ga. to Wis. and R. I.
72. P. Huachucae Ashe. Stem stiffly upright, light-olivaceous, copiously papil-
lose-pubescent, 20-60 cm. tall, the nodes bearded: (taller and more slender,
brighter-green and less densely pubescent: leaf-blades lax, thin, spreading, the
upper surface sparsely short-pilose, or with copious long hairs near the base,
the lower surface pubescent and with a satiny luster in P. Huachucae silvicola.
[P. lanuginosum (Fl. SE. U. S.)]--Fla. to Tex., Nebr., and Me.): leaf-sheaths
pubescent: blades firm, stiffly erect or ascending, the upper surface copiously
short-pilose, the lower densely pubescent: panicle 4-6 cm. long, the axis pilose:
spikelets about 1.7 mm. long. Autumnal phase stiffly erect or ascending, the
branches fascicled. [P. unciphpylmm (Fl. SE. U. S.)]--Prairies and open
grounds, various provinces, N. C. to Calif., S. D., and Me.
73. P. villosissimum Nash. Stem 25-45 cm. tall, erect or ascending: panicle
4-8 cm. long, the branches rather stiffly ascending or spreading: spikelets
about 2.2 mm. long. Autumnal phase finally prostrate, forming a mat, the
leaf-blades not much reduced. [P. atlantioum Nash P. xanthospermum Scribn.
& Mohr]-Dry sandy or sterile soil, woods, and pinelands, various provinces,
Fla. to Tex., Minn., and Mass.-(C. A.)
74. P. pseudopubescens Nash. Resembling P. villosissimum: leaf-blades gla-
brous on upper surface along center or all over: spikelets about 2.3 mm. long.
Autumnal phase stiffly spreading.-Sandy woods and pinelands, Coastal Plain
and adj. provinces, Fla. to Miss., Ill., and Conn.-(Mex.)
75. P. ovale Ell. Stem 20-50 cm. tall, relatively stout, the lower portion and
the leaf-sheaths long-pilose with ascending or appressed hairs: blades nearly
glabrous on upper surface: panicle 5-9 cm. long. Autumnal phase spreading-
decumbent, the stiff stems rather loosely branching, the winter blades very
firm, conspicuously ciliate. [P. ciliiferum Nash]--Dry sandy woods and
pinelands, Coastal Plain, Fla. to Tex. and N. C.-Plant densely tufted.
76. P. wilmingtonense Ashe. Stem 20-40 cm. tall, pilose with soft ascending
hairs, the nodes pilose: leaf-sheaths villous like the stems: blades rather stiff,
ascending, 4-9 cm. long, glabrous on the upper surface, softly pubescent to
nearly glabrous beneath: panicle 5-8 cm. long. Autumnal phase spreading, the
branches crowded, the reduced blades involute-pointed.-Sandy woods, Coastal
Plain, Ala. to N. C.
77. P. malacon Nash. Stem erect or stiffly spreading, 30-50 cm. tall, pubes-
cent with ascending hairs like the leaf-sheaths: blades stiffly ascending, 4-12
cm. long, 3-5 mm. wide, sharply acuminate, puberulent or glabrous above,
often villous on the margin: panicle 4-7 cm. long, the few branches stiffly
ascending, the spikelets on long stiff pedicels. Autumnal phase decumbent-
spreading, the branches appressed. [P. strictifolium Nash]-Dry pinelands
and scrublands, Fla.
78. P. Commonsianum Ashe. Plant olivaceous: stem 20-50 cm. tall, stiffly
ascending or spreading, appressed-strigose or appressed-pilose: leaf-blades firm,
stiffly ascending, glabrous above, strigose or glabrous beneath: panicle 4-8
cm. long. Autumnal phase spreading or prostrate, forming mats.-Sandy
woods and pinelands, Coastal Plain and New England Coast, Fla. to Conn.
79. P. Addisonii Nash. Resembling P. Commonsianum: usually less than 40
cm. tall: leaf-sheaths sparsely ascending-pilose: blades glabrous above, pubes-
cent or glabrous beneath: panicle 2-6 cm. long. Autumnal phase spreading,
freely branching, the branches appressed.-Sandy barrens, often acid, Coastal
Plain and New England Coast, S. C. to Ind. and Mass.
80. P. tsugetorum Nash. Plants rather pale bluish-green: stem 30-50 cm.
high, ascending, sometimes geniculate at base, densely appressed-pubescent:
ligules 1-1.5 mm. long: leaf-blades 4-7 cm. long, 4-7 mm. wide, glabrous
above, appressed-puberulent beneath: spikelets about 1.8 mm. long. Autumnal
phase decumbent-spreading, branched, the branches appressed.-Acid sandy
woods, various provinces, Va. to Tenn., Ill., and Me.
80a. P. columbianum Scribn. Differs from P. tsugetorum in being smaller,
more slender, with the stiffer culms densely crisp-puberulent, and smaller spike-
lets (about 1.5 mm. long).--Sandy woods, various provinces, N. C. to Me.
81. P. sphaerocarpon Ell. Plant light-green: stem 20-55 cm. tall, radiate-
spreading (ascending: ligules 0.3-1 mm. long in P. sphaerooarpon inflatum.-
Tex. to N. C.): leaf-sheaths glabrous, ciliate: ligules obsolete: blades thick and
firm, rough above, smooth beneath: panicle long-exserted, 5-10 cm. long: spike-
lets 1.6-1.8 mm. long, puberulent. Autumnal phase prostrate-spreading, the
branches mostly simple.-Sandy soil, acid woods, thickets, and prairies, various
provinces, Fla. to Tex., Kans., and Vt.-(Mex., C. A., S. A.)
82. P. polyanthes Schult. Plant glabrous or nearly so: stem erect, 30-90
cm. tall: leaf-blades 12-23 cm. long, 15-25 mm. wide: panicle 8-25 cm. long.
Autumnal phase erect, sparsely branched.-Damp ground, woods, thickets,
stream-banks, and prairies, various provinces, Ga. to Tex., Okla., and N. J.
83. P. erectifolium Nash. Stem erect, 30-70 cm. tall: panicle 6-12 cm. long.
Autumnal phase erect, little-branched.-Moist pinelands, prairies and cypress-
ponds, Coastal Plain, Fla. to La. and N. C.-(W. I.)
84. P. curtifolium Nash. Stem weak, slender, 10-30 cm. tall, angled, the
nodes sparsely bearded: leaf-blades spreading or reflexed, 1.5-3 cm. long, 2-5
mm. wide, thin and soft: panicle 2-3 cm. long: spikelets 1.4 mm. long, gla-
brous or minutely pubescent. Autumnal phase weakly spreading, the ultimate
branches in small fascicles. [P. Earlei Nash]-Boggy soil, Coastal Plain
and adj. provinces, Fla. to Ala., Tenn., and S. C.
85. P. tenue Muhl. Stem 20-55 cm. tall, glabrous or the lower part sparsely
appressed-pubescent: leaf-sheaths sparsely appressed-pilose or the upper gla-
brous: panicle 3-5 cm. long: spikelets 1.6 mm. long, puberulent. Autumnal
phase erect or leaning, branching from the middle nodes.-Moist sandy woods,
Coastal Plain, Fla. to N. C.
86. P. albomarginatum Nash. Stem 15-40 cm. tall: leaf-blades thick and firm,
with a thick cartilaginous margin: panicle 3-6 cm. long: spikelets about 1.5
mm. long, puberulent. Autumnal phase spreading, repeatedly branching from
the base.-Low sandy soil, pinelands, and prairies, Coastal Plain, Fla. to La.
and Va.-(W. I., C. A.)
87. P. trifolium Nash. Resembling P. albomarginatum: stem more slender,
leaves less conspicuously crowded at the base, blades less thick and firm. Au-
tumnal phase sparingly branching from the middle and upper nodes.-Low
woods, pinelands, and prairies, Coastal Plain, Fla. to La., Tenn., and N. J.
88. P. vernale H. & C. Stem 15-30 cm. tall, very slender, glabrous: leaves
clustered at the base, the blades thin, soft, 2-7 cm. long, 3-5 mm. wide: panicles
1.5-3 cm. long: spikelets 1.5 mm. long, pubescent. Autumnal phase forming
soft mats.-Moist places, Coastal Plain, Fla. to Miss.
89. P. chamaelonche Trin. Stem 10-20 cm. tall, glabrous. Autumnal phase
freely branching from the base and lower nodes. [P. Baldwinii Nutt.]-Open
sandy soil, pinelands, old fields, and hammocks, Coastal Plain, Fla. to Miss.
and N. C.--(W. I.)
90. P. glabrifolium Nash. Resembling P. chamaelonche: stem as much as 50
cm. tall. Autumnal phase freely branching from the middle and upper nodes.
-Low sandy pinelands, pen. Fla.
91. P. ensifolium Baldw. Stem 20-40 cm. tall, slender, glabrous: panicle 1.5-4
cm. long: spikelets glabrous or puberulent. Autumnal phase spreading or re-
clining, sparingly branching. [P. Cuthbertii Ashe P. glabrissimum Ashe]-
Wet places, woods, and pinelands, often in acid soil, Coastal Plain, Ga. to
Miss. and N. J.
92. P. concinnius H. & C. Stem very slender, 12-50 cm. tall, glabrous,
puberulent at the nodes: panicle 3-6 cm. long. Autumnal phase radiate-
spreading, sparingly branched. [P. gracilicaule Na-sh]-Moist, sandy soil,
Piedmont and Appalachian Valley, Ga. and Ala.
93. P. breve H. & C. Stem erect, 5-15 cm. tall: panicle 1.5-4 cm. long:
spikelets about 1.3 mm. long. Autumnal phase spreading, freely branching
from the upper and middle nodes.-Low sandy or rocky pinelands, pen. Fla.
94. P. flavovirens Nash. Stem slender, ascending or spreading, 15-30 cm.
tall, the lower leaves somewhat crowded: blades 2-5 cm. long, 3-4 mm. wide:
spikelets about 1.4 mm. long. Autumnal phase spreading, branching from the
lower and middle nodes.-Moist shady soil, Coastal Plain, Fla. to Miss. and
95. P. portoricense Desv. Stem 15-30 cm. tall: leaf-blades 2-5 cm. long,
3-6 mm. wide, firm, glabrous to puberulent: panicle 2-4 cm. long: spikelets
puberulent. Autumnal phase ascending from a decumbent base, repeatedly
branching.-Sandy pinelands, Coastal Plain, Fla. to Tex. and N. C.-(W. I.)
96. P. Webberianum Nash. Stem 20-50 cm. tall, rather stout: leaf-blades
3-9 cm. long, 4-12 mm. wide: panicle 4-10 cm. long: spikelets 2.3-2.5 mm.
long, glabrous or puberulent. Autumnal phase spreading or decumbent, flabel-
lately branched.-Low pinelands, prairies, and fields, Coastal Plain, Fla.
to N. C.
97. P. patentifolium Nash. Stem 25-55 cm. tall: leaf-blades stiffly spreading,
2.5-8 cm. long: panicle 3-7 cm. long: spikelets puberulent or nearly glabrous.
Autumnal phase decumbent or spreading, branched from the middle and upper
nodes.-Dry sand, prairies, pinelands, and hammocks, Coastal Plain, Fla. to
Miss. and Ga.