Official Organ of the Florida Entomological Society
VOL. XXXI SEPTEMBER, 1948 No. 3
KEY TO FLORIDA Triatoma WITH
ADDITIONAL DISTRIBUTION RECORDS FOR THE SPECIES
D. C. THURMAN, JR.,2 J. A. MULRENNAN,2 ERNESTINE BASHAM 4 and
DOYLE J. TAYLOR '
Chagas in 1909 (1)6 first demonstrated that Triatoma me-
gista Burmeister was an intermediate host of Trypanosoma cruzi
(Chagas), a parasitic protozoan, causing a disease of children
in South America. Since that time several papers by medical
entomologists and parasitologists on the triatomines of North
America have appeared. The most comprehensive of these is
the bulletin by Usinger (2) on the subfamily Triatominae which
gives descriptions and distribution data for species known from
North and Central America and the West Indies. Usinger's
work includes two species and two sub-species of the genus
Triatoma which are known from Florida, namely: Triatoma
sanguisuga (LeConte), Triatoma sanguisuga ambigua (Neiva),
Triatoma lecticularius (Stal), and Triatoma lecticularius flori-
In connection with premises inspections in evaluating the
control of malaria vector Anopheles quadrimaculatus Say by re-
sidual house spraying with DDT, additional distribution records
for the Florida species of Triatoma were obtained. These records
'A contribution of the Communicable Disease Center Activities, U. S.
Public Health Service and the Florida State Board of Health, Jacksonville,
2 S. A. Sanitarian (R), U. S. Public Health Service.
SChief Entomologist, Division of Entomology, Florida State Board of
4Entomologist, C. D. C. Activities, U. S. Public Health Service.
'Entomologist, C. D. C. Activities, U. S. Public Health Service.
Italic figures in parentheses refer to Literature Cited.
VOL. XXXI-No. 3
* Triatomo songuisugo ambiguo (Neivo)
* Triotomo sonquisuqo (Le Conte)
t Triotomo lecticulorius (Stol)
x Triotomo lecticulorius floridono Usinger
Figure No.lCounties From Which Triotoma spp.Hove Been Reported.
which represent observations over a period of four years by
Florida State Board of Health employees appear in Tables I
and II. A map of Florida, Figure I, presents the known dis-
tribution of the species of Triatoma, (including Usinger's
For those persons who work with insects of medical im-
portance in Florida a key is included which will be of assistance
in determining species of Triatoma collected in the state. Any-
one interested in studying the genus, or in the collections of
Triatomines from other areas, should refer to Usinger's more
TABLE I.-COLLECTION RECORDS OF Triatoma spp.- IN FLORIDA FROM 1944 THROUGH 1946.
County Locality Date Species Number and Stage Collector
St. Johns .-.......... -- Hastings ........ Oct. T.s. ambigua, 1N (skin) ........... D. C. Thurman
Citrus .................--. Inverness ......... 24 April T. sanguisuga, 1F -....-...--...---...- D. C. Thurman, J. Lovett
Citrus .........-........ Inverness ............ 24 April T. lecticularius, 1M -.............. D. C. Thurman, J. Lovett
Citrus ................... Inverness --..-..... 24 April T.s. ambigua, 3M, 1F ............... D. C. Thurman, J. Lovett
Citrus .............---.-. Inverness ....---..... 6 June T.s. ambigua, 1F ........................ D. C. Thurman, J. Lovett
Citrus ............-------. Inverness ............ 6 June T. lecticularius, 1F ...............---. D. C. Thurman, J. Lovett
Citrus .........-- ..-.... Inverness ........... 24 Aug. T.s. ambigua, 1F ........................ J. C. Burgess
Suwannee .......---..... Branford ........... 7 Oct. T.s. ambigua, 1F .............-.......... M. Braswell
Suwannee ....... Branford .---....-. 7 Oct. T. lecticularius, 1 ..........-..-......... M. Braswell
Citrus .............-- ..-- Lecanto ................ 16 Aug. T.s. ambigua, 13M, 6F, 1N .... D. C. Thurman, A. J. Obermuller
Citrus ........-........- Lecanto ................ 16 Aug. T. lecticularius, 1M ............-- ..... D. C. Thurman, A. J. Obermuller
Citrus .................... Inverness --........ 17 Aug. T.s. ambigua, 1M ........................ D. C. Thurman, A. J. Obermuller
Duval ...................... Jacksonville ..... 22 May T.s. ambigua, 1M ....................... Dr. H. Hansen
Duval ...........-.........- Jacksonville ...... 2 July T.s. ambigua, 1M ........................ Dr. H. Hansen
Levy ....--.......---...----- Chiefland ............. 28 Aug. T.s. ambigua, 2F .......................... A. J. Obermuller
Levy ........................ --------------Otter Creek ........ 24 Sept. T.s. ambigua, F ----..--.......-.....-------- A. J. Obermuller
Marion ................. Fairchild ............ Aug. T.s. ambigua, 1 --....-..................... D. C. Thurman
VOL. XXXI-No. 3 61
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THE FLORIDA ENTOMOLOGIST
Genus Triatoma Laporte
Key to Florida Species of Adult Triatoma o
1. Body naked .............. .........--- ------------------- 2
Body pubescent .............................----------- 3
2. Length more than 19 mm. .....---.......-- ..... ------------- sanguisuga
Length less than 19 mm. ........................ sanguisuga ambigua
3. Length 24 mm. ...........--.. ~~.. ........ ......... lecticularius
Length 20 mm. ............-.....................---- .. lecticularius floridana
No natural infections with T. cruzi (Chagas) have been
reported for the species and sub-species known from Florida,
although Packchanian (3) demonstrated that T. sanguisuga
ambigua (Neiva) could be experimentally infected with T. cruzi.
1. Chagas, C. Ueber eine neve trypanosomiasis des menschens. Memories
do Instuto Oswaldo Cruz. 1: 159-218. 1909.
2. Usinger, Robert L. The Triatominae of North and Central America
and the West Indies and their public health significance. Public Health
Bulletin No. 288, Federal Security Agency, U. S. Public Health 81 pps.
3. Packchanian, A. Experimental transmission of Trypanosoma cruzi in-
fection in animals by Triatoma sanguisuga. Pub. Health Rep. 55: 1526.
AN AGRONOMIZED LEAF-MINER AND ITS PARASITES
By JAMES G. NEEDHAM
In early December 1947 at the Archbold Biological Station,
Florida, there appeared in great abundance on the leaves of
the common weed Bidens pilosa the work of Dipterous leaf-
miner that had before been noticed but sparingly. A few could
be found on almost any Bidens clump, and half the leaves on
some single plants were infested. Finding grown larvae in
some of them, I spent about an hour collecting and selecting
some fifty of them, and put them in a rearing jar, the issue
from which I will here briefly relate.
By holding an infested leaflet to the light and looking through
it with a lens I could see by transparency a Dipterous larva
working within. That it was an Agromyzid larva was indicated
by its manner of working. It lay on its side swinging its mouth-
VOL. XXXI-No. 3
hooks up and down in the plane of the leaf surface, tearing
fresh leaf tissue on each down stroke, and thus liberating the
sap for food. So it cut a swath as wide as the swing of its
mouth-hooks. And it left in torn cell walls a record of its
strokes like the slanting stubble in an oat field that has been
mown by a scythe; all slant in the same direction, the swath
crossed by parallel curving lines formed by successive strokes.
The mine is begun at the tip of a leaflet, and is continued,
full depth, across the whole width of the leaflet for a third or
a half of its length. The mine turns brown as fast as it is
sucked dry and becomes shrivelled and more or less collapsed
I had hardly more than stocked my rearing jar when a few
of the brood began to leave their mines to find a place for pupa-
tion. They were not hard to satisfy: almost any dry smooth
surface would do. Some settled high, some low on the inner
side of the glass jar, and some on the outside of the leaflets
piled in the bottom.
Each larva emerged from its mine soft and sticky and nearly
as shapeless as a shell-less egg. As it slid along to a place of
pupation it seemed tb be about to deliquesce and melt away;
but when it stopped it quickly dried and hardened into a more
or less loaf-shaped puparium closely adherent by the flat under
surface. At first it was honey-yellow but soon it turned brown.
Four species of insects emerged from the mines in the rear-
ing jar: one, the leaf-miner; the others, its parasites. These
were preserved daily as they emerged, and sent to Dr. C. F. W.
Muesebeck, to whom I owe my thanks for determination. They
were the following:
Agromyza maculosa Malloch (det. C. T. Greene). Dr. Greene
states that Bidens pilosa is a new host plant for this species.
Chrysocharis sp? (Eulophidae det. A. B. Gahan). A single
specimen; emerged December 23, 1947.
Opius n. sp. and Oenonogaster n. sp. (Braconidae det. C. F.
W. Muesebeck; numerous specimens). Dr. Muesebeck says that
the two are certainly undescribed. Emergences of the Agromy-
zas and of these Braconid parasites occurred on January 8th,
10th, 12th and 14th, 1948, and these parasites were somewhat
more numerous than the flies that make the mines.
Evidently I had come upon an upsurge of parasitism, for
shortly thereafter and for the three months of my subsequent
stay at the Archbold Laboratory, hardly a single leaf mine of
THE FLORIDA ENTOMOLOGIST
this species could be found. The Braconids seem to have de-
stroyed their own food supply.
Specimens of the parasites are in the United States National
Museum awaiting description.
THE PROGRESS OF ENTOMOLOGY
W. G. BRUCE
United States Department of Agriculture
Agricultural Research Administration
Bureau of Entomology and Plant Quarantine
The present widespread interest in entomology is a direct
result of the excellence of the work done by entomologists in
the war effort. The urgent demands for more effective methods
and materials for controlling insects, especially insect vectors
of disease (malaria, yellow fever, epidemic typhus, tsutsuga-
mushi fever, etc.), accelerated research in entomology and the
discovery and development of new and remarkable insecticides.
Certainly the entomologist had no small part in shortening the
duration of the war. By reducing the loss.of life and man-hours
caused by insect-borne diseases and by preventing insect damage
to food, clothing, and other property, the entomologist played
a very important part in winning the war.
It is needless to enumerate each and every contribution made
by the entomologists during the war or to discuss in detail each
important insect-borne disease, its vector, and its control, for
all this has been given adequate publicity and is now common
knowledge. Suffice to say, the entomologists can be justly proud
of their part in the war effort.
For many years prior to the war, entomology was looked
upon with polite tolerance. It has now reached the eminence
of other learned professions, commands their respect, and en-
joys their cooperation. In recent years the general public has
become more "insect conscious" and realizes more than ever
before the importance of insect control.
To the early entomologists, especially the older members of
our entomological organizations, goes much of the credit for
the present status of our profession. With devotion to duty,
sincerity of purpose, and keen foresight, they banded together
for the betterment of the individual, the interchange of technical
information, the cementing of friendships, and the planning
for the future. They formed societies and struggled through
VOL. XXXI-No. 3
the lean years to hold their organizations together. It was
these scientists who, in time of emergency, were prepared and
ready to solve the momentous problems with which they were
confronted. It is only fitting that tribute be paid to the founders
and former officers of the Florida Entomological Society for
their devotion to and foresight in the field of entomology, for
their part in building this Society, for their inspiration to the
younger entomologists, and for their part in elevating the science
of entomology to its present level.
But their work is by no means completed. Their long and
diversified experience is needed to guide and stabilize the Society
through the coming years. Their inspiration is still needed by
their co-workers and by the younger entomologists. There are
many problems yet to be solved, and their solution is demanded
by the public in its desire for more effective methods of con-
trolling insect pests.
We are on the threshold of a new era for entomology, an
era that demands creative thought, intensive research, more
extension service, better organization, more accurate insect
surveys, more adequately trained entomologists, more coopera-
tion between research personnel and those with the Extension
Services, the Public Health Service, industry, and commercial
Research in entomology, having profited by the war experi-
ence, appears to be on a sound footing. Its progress is limited
only by inadequate funds and insufficient personnel. Many in-
sect problems still await the attention of the research worker.
Some new insect pests present new problems. Some of the old
control measures need improvement. Numerous new insecti-
cides-particularly DDT, TDE, chlordane, benzene hexachloride,
chlorinated camphene, and parathion-must be tested for toxicity
to the insect and to the host animal or plant. The fields of
chemotherapy and insect transmission of disease offer unlimited
opportunities to the research entomologist.
Those of us who are interested in insects affecting livestock
should devise an insect-control calendar for stockmen-a calen-
dar of the various ectoparasites of livestock, the materials and
methods for control, and the approximate dates for treatment.
Insect incidence and abundance and climatological conditions
vary in different parts of the United States, and therefore dif-
ferent schedules must be formulated to apply to different sec-
tions of the country.
THE FLORIDA ENTOMOLOGIST
We are thinking today, more than ever before, in terms of
insect eradication. Even if the eradication of some insects may
not appear feasible today, it is time to think of eradication,
to learn enough about the insect and its control to justify such
a program. Screwworms, the most destructive insect pest
affecting livestock in Florida, can be eradicated from the South-
east, and that region can be kept free of reinfestation. It is
not unreasonable to assume that, with our present knowledge
and present methods of control, cattle lice and horn flies can
be eradicated in some of the States where livestock is a highly
organized industry, and where the cooperation of the stockmen
can be assured.
Yes, there are plenty of opportunities for the research ento-
mologist who has the initiative and the ability for creative
thinking, backed by adequate training in entomology and re-
The Extension Services in the various States are now taking
a keen interest in entomology, and during the past two or three
years they have done their greatest work in this field. It is
apparent that these Services could be, and certainly should be,
important factors in the development of practical insect control.
They are in a position, not only to distribute information con-
cerning insect control, but actually to demonstrate to farmers
and stockmen that insect control is both practical and profitable.
Too often, heretofore, the results of good research have been
buried in isolated reports and publications while the would-be
beneficiaries still struggled with problems already solved. To-
day the Extension Services in many States are keeping pace
with the rapid strides in entomological research, and not only
promptly relay the new information to the citizens, but by lec-
tures and demonstrations teach the new and improved methods
of insect control. Crop dusting and the spraying of livestock
are only two of the many examples that could be cited. You
have had some excellent examples of livestock spraying here
in Florida. More of this type of work must be done if the
fruits of research are to be properly harvested. Extension
Services should make an effort to maintain the present interest
in entomology, to have at least one extension entomologist in
each State, to give some entomological training to all county
agents, and to cooperate closely with research entomologists.
Cooperation between Federal and State agencies, and of
these agencies with the Extension Service and industry, is of
VOL. XXXI-No. 3
prime importance for the best interests of research and exten-
sion. This close cooperation is rapidly becoming a reality. About
one year ago two significant conferences were held-one at
Oklahoma City, Oklahoma, and the other at Cheyenne, Wyom-
ing-at which representatives from all States west of the Missis-
sippi River, with the exception of Minnesota and California,
met to discuss the control of insect pests affecting livestock.
The State representatives included entomologists, veterinarians,
and animal husbandmen in the fields of research and extension.
The United States Department of Agriculture was represented
by both research and extension workers. The conferences were
informal and permitted a thorough discussion of all problems
in veterinary entomology that are important in that section of
the country. The information presented was carefully analyzed
and control recommendations were formulated.' Recommenda-
tions were also made for additional research and extension. The
success of these conferences was indicated by the enthusiastic
participation of all the representatives and by the unanimous
opinion that such conferences should be annual events.
Just last month a similar and very successful conference
was held at Atlanta, Georgia. Research and extension repre-
sentatives came from Florida, Georgia, Alabama, Mississippi,
Louisiana, Kentucky, Tennessee, South Carolina, and North
Carolina. The United States Department of Agriculture was
represented by members of the Bureau of Entomology and Plant
Quarantine, the Bureau of Animal Industry, and the Extension
Service. Sectional conferences of this nature should be held
each year and in such locations as to encompass the entire
More active insect pest surveys, by the employment of full-
time scouts, would aid materially in reducing the losses due
to insect attack. Funds expended in this enterprise should
result in savings far in excess of the cost of such a project.
This information would provide a basis for the forecasting of
outbreaks and help in the detection of new insect pests before
they become established. It would thereby enable farmers and
stockmen to make accurate estimates of the amounts of critical
materials needed, and to obtain insecticides and equipment for
controlling the pests before they do serious injury. These scouts
could perform another valuable service by collecting data on
the actual losses of animals due to insect attack. Many of our
present estimates on losses caused by insects are mere guess-
THE FLORIDA ENTOMOLOGIST
work. We need more facts if we are to evaluate these losses
The enforcement of our present quarantines to prohibit or
regulate the importation or interstate movement of injurious
insects must be continued. This phase of enomological work
has become more complicated by the tremendous increase of
air traffic into the United States, and we must continue to be on
the alert for immigrant pests.
This discussion briefly reviews the present status of ento-
mology and looks toward the distant horizon. We cannot rest
on our present laurels. There are many problems to be solved.
It is up to the entomologists to carry on. To the older entomolo-
gists we can truthfully say-"Well done, good and faithful
servant"-and to the younger entomologists may we suggest-
"Go thou and do likewise."
RESULTS OF TESTS MADE WITH SOME NEWER
INSECTICIDES FOR THE CONTROL OF THE
RED HARVESTER ANT
Pogonomyrmex barbatus (F. Smith)
PAUL T. RIHERD
Assistant Entomologist, Texas Agricultural Experiment Station
A test was conducted from July 30, 1947 to October 23,
1947, to determine if some of the newer insecticides could be
used as a simplified control for the red harvester ant, Pogo-
nomyrmex barbatus (F. Smith). The materials used were in
dust form, and included the following insecticides: 6 benzene
hexachloride (gamma isomer), 5% DDT, 5% chlordane, and
20% chlorinated champhene (Toxaphene).
Strong, well established colonies located in a typical Texas
Gulf Coast pasture were selected for the test. Five colonies
were treated with each material. The treatments were made
by applying approximately one ounce of the dust over the mound
around the entrance to the nest by hand in such a manner that
the ants leaving or entering the nest would have to pass through
the insecticide. The dusts were applied by taking the dust in
the hand and strewing it in the manner of sowing seed broad-
cast, starting at the entrance and extending outward allowing
enough dust to just cover the surface of the soil. Each nest
VOL. XXXI-No. 3
was treated five times during the test. Observations of the
nests were made at times when untreated colonies showed nor-
The results of the treatments were determined by making
observations of the nests and recording the activity of the ants
at each nest. Colonies with no activity were scored 1; colonies
with one to fifty ants present 2; colonies with more than fifty
ants but showing a definite weakened condition were scored 3;
and colonies where little or no decrease in the strength of the
colony was evident were given a rating of 4. Hills with fresh-
dead ants present about the nest were recorded.
A summary of the data gathered from these tests is pre-
sented in the accompanying Table. It was observed that all
activity at some nests ceased on the second or third day after
treatment and remained inactive from three to five days. Kick-
ing into these hills disclosed many unaffected ants.
The duration of the test was 83 days. At the end of the
test no colonies had been eradicated. Of the five colonies treated
with 6% benzene hexachloride, three were in a weakened con-
dition, and two with very little activity. Fresh-dead ants were
present at one nest on October 22, twelve days after the last
treatment. Of the five colonies treated with 5%, DDT three
showed little or no decrease in the strength of the colonies, and
two in a definitely weakened condition. Fresh-dead ants were
present at one nest on August 8, eleven days after treatment.
At the end of the test the colonies treated with 20% Toxaphene
showed three colonies in a weakened condition, one with very
little activity, and one with little or no decrease in the strength
evident. Fresh-dead ants were present at one nest on October
22, fourteen days after treatment. On October 8, thirty-three
days after the last previous treatment fresh-dead ants were
present at three hills, one of which showed no activity. No
unaffected ants were revealed by kicking into the mound.
Many dead ants were present about all the nests treated
the day after the first applications were made. Observations
were not made the first day after subsequent applications.
70 THE FLORIDA ENTOMOLOGIST
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VOL. XXXI-No. 3
THE RED STENODYNERUS OF FLORIDA
By RICHARD M. BOHART
University of California, Davis
The genus Stenodynerus Saussure is represented in Florida
by 17 known species and subspecies including 5 described in
this paper. They are not closely related within the genus but
14 of them have in common a characteristic type of dull red
markings associated with a distribution limited to southeastern
United States or to Florida alone. Most of these red-marked
forms are merely subspecies of more widely distributed yellow-
marked forms occurring to the north and west. The only ex-
ceptions appear to be histrio, australis, beameri and possibly
bifurcus. The last named seems very close structurally to S.
pedestris (Saussure) and may be a subspecies of it.
The red-marked Stenodynerus of Florida are abundant and
constitute an outstanding part of the endemic fauna. Indeed,
it is almost always possible to recognize a Florida specimen by
its markings without determining the species. Two other areas
in which the solitary vespids can be used as indicators are Lower
California, where reduced punctuation is the rule, and the
Hawaiian Islands where black is the predominant color. In
addition to Stenodynerus many other Floridan vespids,1 sphe-
coids, bees, and even some flies exhibit the same shade of red.
The collections examined which contained appreciable num-
bers of Florida material were in the U. S. National Museum,
Museum of Comparative Zoology at Harvard, Academy of
Natural Sciences at Philadelphia, American Museum of Natural
History, California Academy of Sciences, Cornell University,
and University of Kansas. In addition, my brother, G. E.
Bohart, and I collected several hundred specimens in the vicin-
ities of Cocoa and Orlando.
KEY TO THE RED-MARKED STENODYNERUS OF FLORIDA
1. Parategulae slender, somewhat to strongly incurved along oblique
inner margin," and usually hooked or pointed toward apex.....-.. 2
1Examples are Eumenes smithii Saussure, Leptochilus tylocephalus (R.
Bohart), Rygchiumn foraminatum apopkense (Robertson), Pachodynerus
erynnis (Lepeletier), and Zethus slossonae Fox.
2 The parategula is the mesonotal projection directly behind the tegula;
it is usually colored but its edge is membranous and the margin is outside
the colored portion.
THE 'FLORIDA ENTOMOLOGIST
Parategulae broadened, outcurved or at least straight along oblique
inner margin, usually broadly rounded at apex ............................ 7
2. Intercellar area with tubercles, which may be weakly developed; inter-
antennal spot linear, not much broadened above ............................ 3
Interocellar area flat or concave, without tubercles; interantennal spot
sometimes broadened above --...----.........-----.....------- -------------- 5
EXPLANATION OF FIGURES
Figs. 1-4, Stenodynerus lineatifrons Bohart, holotype male, front view
of head, parategula, flattened aedeagus, and extension of paramere, re-
Figs. 5-8, Stenodynerus beameri Bohart, holotype male, front view of
head, parategula, flattened aedeagus, and extension of paramere, respec-
VOL. XXXI-No. 3 73
3. Summit of tergite I without a transverse ridge; tergite III apically
banded and tergite II spotted, at least in male; interocellar tubercles
weak, propodeum not forming a horizontal shelf behind postscutel-
lum; male with mid femur toothed, hind femur somewhat swollen,
and antennal hook stout ........................ fundatiformis (Robertson)
Summit of tergite I with a transverse ridge; tergite III and those
following dark, tergite II unspotted; propodeum forming a distinct
horizontal shelf below postscutellum, legs of male not modified as
above, antennal hook slender .................... ...---- .......-- ...--------- 4
4. Acarinarium present beneath lengthened apex of tergite II; sculpture
very coarse, punctures of mesonotum nearly as large as ocelli;
longitudinal ridges at base of sternite II separated by about 2
ocellus diameters near middle of body; male mid femur not depressed
beneath at base; tergite II frequently all dark....histrio (Lepeletier)
Acarinarium absent; sculpture less coarse, punctures of mesonotum
much smaller than ocelli; generally not more than one-half as large;
longitudinal ridges at base of sternite II separated by little more
than 1 ocellus diameter near middle of body; male mid femur de-
pressed beneath at base; tergite II apically banded (figures 1-4)
--....-..-................- .-----------------------------. lineatifrons R. Bohart
5. Sternite II bent outward near base as seen in profile, without a
median crease; acarinarium present; male antennal hook black;
tergite II unspotted ----.------------. perennis anacardivora (Rohwer)
Sternite II evenly convex in profile, with a median basal crease;
acarinarium absent; male antennal hook brown or red ................ 6
6. Tergite I with a distinct, irregular, transverse ridge across its summit;
clypeus spade-like, truncate apically; male with mid femur some-
what distorted; ocelli normal, sternite II trituberculate ...............
................................. --------..--- clypeolatus floridanus Robertson
Tergite I somewhat roughened at summit but not ridged; clypeus not
spade-like; male with ocelli larger than usual, sternite II and mid
femur normal ............................................... australis (Robertson)
7. Without an acarinarium beneath apex of tergite I, juncture of I and
II marked at least laterally by a transverse row of pit-like de-
pressions; no smooth, raised area on either side of tergite I
behind summit; interocellar area with tubercles; flagellum of male
usually pale beneath almost to apex ...........-................................. 8
With an acarinarium beneath lengthened apex of tergite I, juncture of
I and II smooth ........-...--- ---...---.... -------. ----........... 11
8. Sternite II with coarse punctures toward basal middle; male clypeus
coarsely punctured and sharply incised at apex, female unknown
(figures 5-8) ................. ---..........-- ......... --------beameri R. Bohart
Sternite II rather finely punctured toward basal middle; male clypeus
moderately incised at apex --......... ----............... ...............-- 9
9. Tergite I without a row of large punctures across summit; sternite
II with preapical pale spots which may be very large, apical band
complete; segments III and following, or some of them, yellow-
marked .................------.................... .. ---oculeus (Robertson)
THE FLORIDA ENTOMOLOGIST
Tergite I with a row of large punctures across summit; sternite II
without preapical pale spots; segments II and following dark.... 10
10. Interantennal spot narrowly wedge-shaped, often linear; male clypeus
rather coarsely punctured, apex broader than median ocellus
(figures 1-4) .................... .......------ .................... lineatifrons R. Bohart
Interantennal spot broadly wedge-shaped, not linear; clypeus un-
usually long and apically narrowed in both sexes, that of male
rather finely punctured, apex about as broad as median ocellus
-.......-..........-----------..............-- -----------... ammonia (Saussure)
11. Tergite I not as broad as length of II beyond acarinarium; ridge across
summit of tergite I low but fairly distinct, without a smooth raised
area on either side behind summit; interocellar tubercles low and
narrow; mid femur of male with a definite basoventral depression
--------------------------------.............................. bifurcus (Robertson)
Tergite I about as broad as length of II beyond acarinarium; tergite
I usually with a smooth, pale-marked raised area on either side
behind summit; mid femur of male not depressed basoventrally.... 12
12. Tergite I with numerous silky hairs of 1 to 3 ocellus diameters in
length located at summit and extending back at least to middle
of horizontal surface ....---..---..-....- ............------..-.......---- ....----------.... 13
Tergite I without long hairs or with a few moderate ones near sum-
m it only .................................. ................. ................... 14
13. Interocellar tubercles present, rather low in female but bulging in
male; longer hairs of tergite I becoming sparse towards apex of
segment; male ocelli small, front ocellus about one-half as broad
as interantennal area and separated by about twice its diameter
from lateral ocelli ...............................-----------------.... bicornis (Robertson)
Interocellar area somewhat raised and shiny but not tuberculate;
longer hairs of tergite I thick toward apex of segment; male ocelli
large, front ocellus as broad as interantennal area and separated
by about its diameter from lateral ocelli .-- .......-- --- .......
--- -------------..----.------. saecularis rufulus R. Bohart
14. Tergite I with a strong ridge across summit; tergite II without an
entrance depression to acarinarium, unspotted; male clypeus
sparsely punctured, weakly incised apically; flagellum broadly red
on basal half in both sexes .....---.....- fulvipes rufovestis R. Bohart
Tergite 1 without a ridge or large punctures across summit; tergite
II with an entrance depression to acarinarium (visible only when
II is bent at an angle with I); male clypeus coarsely punctured
and very deeply incised apically;3 flagellum mostly black.............
----.v------------------ agus slossonae R. Bohart
Stenodynerus (Stenodynerus) fundatiformis (Robertson)
Odynerus fundatiformis Robertson, 1901. Trans. Amer. Ent.
Soc. 27: 197. Male, Inverness, Florida.
. Male character taken from specimens of typical vagus.
VOL. XXXI-No. 3
SPECIMENS STUDIED.-Florida: Titusville, DeFuniak Springs,
Sanford, Suwannee Springs, Cocoa, Fort Mead, Hilliard, Fruit-
ville, Branford, Lacoochee, Lamont, Naples, Blountstown, Mul-
berry, Fort Worth; Alabama: Mobile; Missouri: Brandon; Ar-
kansas: Fort Smith; Texas: Frio County; Mississippi: Orange
Grove; Georgia: Valdosta, Wadley, Okefenokee Swamp, Pratts-
burg; South Carolina: St. Mathews.
Stenodynerus (Stenodynerus) oculeus (Robertson)
Odynerus oculeus Robertson, 1901. Trans. Amer. Ent. Soc.
27: 197. Male, female, Orlando, Florida.
SPECIMENS STUDIED.-Florida: Inverness, Hilliard, Dade
City, St. Petersburg; Georgia: Okefenokee Swamp.
Stenodynerus (Stenodynerus) australis (Robertson)
Odynerus australis Robertson, 1901. Trans, Amer. Ent. Soc.
27: 197. Male, female, Inverness, Florida.
SPECIMENS STUDIED.-Florida: Inverness, Lacoochee, Or-
lando, Palm Beach, Sanford.
Stenodynerus (Stenodynerus) beameri, new species
MALE.-Black, deep yellow and reddish. Deep yellow or orange-yellow
are: mandible mostly, clypeus, scape in front, inner surface of flagellum,
lower orbit, interantennal line broadened above, postocular spot, 2 barely
joined humeral spots, tegula, spot beneath, parategula, postscutellum
mostly, propodeal angles largely, legs partly, abdominal tergite I except
for basal slope and small triangular spot along summit (absent in one
paratype, small in another), apical margins of tergite II broadly, tergite
IV very weakly and sternite II. Brownish red are: Legs partly, basal
slope of tergite I partly, free lateral spot on tergite II (absent in para-
types), large spots at base of sternite II. Wings deeply brown stained
and somewhat violaceous. Pubescence short and inconspicuous. Punctura-
tion moderate to coarse. Punctures of clypeus deep and rather close,
those of front and mesonotum coarse and close, those of propodeum above
pit-like, those of horizontal surface of tergite I coarse and close, becoming
larger toward summit where they form a poorly defined ridge, those toward
apex of tergite II very coarse and somewhat elongate in a cribrose band.
Front of head and parategula as in figs. 5 and 6; last antennal segment
somewhat flattened, curved, reaching base of tenth; interocellar area with
narrow tubercles not bridged over front ocellus; indistinct ocular swellings
present; propodeum forming a narrow but distinct shelf behind postscutel-
lum; pits across base of tergite II becoming obsolete medially; tergite II
with an oblique apical reflex of 1.5 ocellus diameters (1 to 2 in paratypes);
sternite II rather evenly convex and with a basomedian crease; genitalia
as in figs. 7 and 8, aedeagus with sharp median expansion and notched
THE FLORIDA ENTOMOLOGIST
submedian expansion, extension of paramere peculiar in form. Length
to apex of second tergite 7.0 mm.
HOLOTYPE, male, Hilliard, Florida, August 19, 1930 (R. H. Beamer).
PARATYPE, 2 males, Gainesville, Florida, October 2, 1914. Type in collection
of University of Kansas.
Externally, beameri resembles closely the more yellow northern speci-
mens of S. (Parancistrocerus) bifurcus (Robt.). The acarinarium under
the slightly lengthened tergite I of the latter and the fact that the first
flagellar segment is distinctly longer than the next 2, instead of nearly
equal as in beameri can be used for separation characters. However, the
male genitalia of beameri are unique.
Stenodynerus (Stenodynerus) lii( tif;rons, new species
MALE.-Black, deep red and dull yellow. Red are: mandible at tip,
basal 3 antennal segments, flagellum beneath as far as tenth segment,
lower orbit, postocular spot, 2 nearly confluent humeral spots, tegula, spot
beneath, parategula, postscutellum, horizontal surface of tergite I and
sternite I. Clypeus yellow. Dull reddish yellow are: linear interantennal
mark, legs except for coxae partly, narrow apical bands of tergites I and
II, and sternite II. Wings brownish, slightly violaceous. Pubescence
short, fulvous on vertex and notum, silvery on clypeus, pleuron and ab-
domen. Puncturation moderate on clypeus, coarse and fairly close on
front, mesonotum, and tergite I except for dark basal part; an undulating
row of large shallow punctures across summit of tergite I outlining an
indistinct ridge, propodeum with pit-like punctures above. Punctures of
tergite II coarse but well spaced, becoming a little larger and closer just
before apex. Front of head and parategula as in figs. 1 and 2, in some
male paratypes parategula has a broader membranous inner (posterior)
margin; last antennal segment rather cylindrical, curved, reaching apex
of tenth; interocellar area with 2 smooth tubercles which are not bridged
over front ocellus; humeral angles weak, propodeum forming a distinct
rough shelf below postscutellum. Mid femur with a basal depression be-
neath; tergite I more than half as long as broad in dorsal view; tergite
II with apical reflex less than 1 ocellus diameter; sternite II with a median
basal crease. Extension of paramere with a large many-toothed basal
crest (fig. 4), aedeagus as in fig. 3. Length to apex of second tergite
FEMALE.-Mandible and legs mostly reddish, first 4 antennal segments
red, a few others partly reddish, propodeum with a red lateral spot, a
small lateral spot sometimes present on tergite II, clypeus with a curved
reddish spot on basal one-third, orbital dots present. Vertex pit about
as large as on ocellus. Length to apex of second tergite 9.0 mm.
HOLOTYPE, male, Jacksonville, Florida (W. H. Ashmead). PARATYPES,
4 males and 11 females from the following Florida localities: Jacksonville
(W. H. Ashmead), Orange Co. (W. A. Hier), Palm Beach, Cocoa (G.
Bohart). One female paratype, Carolina Beach, North Carolina (F. S.
Blanton); 1 female paratype, McClellanville, South Carolina (H. K.
Townes). Paratypes were collected from May through July. Type in U. S.
VOL. XXXI-No. 3
This species resembles ammonia (Saussure) and australis
(Robertson) but differs from both of these in that the basal
part of tergite I is dark. Also, the parategulae are narrower
than in ammonia and the frontal mark in lineatifrons is narrow
instead of widened above as in the other 2 species.
Stenodynerus (Stenodynerus) ammonia (Saussure)
Odynerus ammonia Saussure, 1853. Etudes sur la Families
des Vespides 1: 144. Female, "Carolina".
SPECIMENS STUDIED.-Florida: Cocoa, Royal Palm, Cudjoe
Key, Charles Harbor, Lacoochee, Cedar Keys, Hilliard, Orlando,
Capron, Jacksonville, Vilano Beach, Lower Matecumbe Key,
Stenodynerus (Stenodynerus) clypeolatus
Odynerus floridanus Robertson, 1901. Trans. Amer. Ent.
Soc. 27: 197. Female, Inverness, Florida.
SPECIMENS STUDIED.-Florida: Charles Harbor, Palm Beach,
Gladeland, Vero Beach, Cocoa, Miami, Brighton, Lower Mate-
cumbe Key, Inverness.
Stenodynerus (Parancistrocerus) vagus slossonae,
FEMALE.-Marked as in typical vagus Saussure but with yellow mark-
ings replaced by orange or dull red. Reddish are: mandible, antenna to-
ward base beneath, clypeus across base, interantennal and orbital spots,
postorbital spot, pronotal spot, tegula, spot beneath, parategula, post-
scutellum, sides of propodeum, legs mostly, apical margin of tergites I
and II, that of I attached to large oblique spot on summit, free lateral
spot on tergite II, lateral apical spot on sternite II. Wings brownish.
Structure as in typical vagus with robust form, stout parategula, short
tergite II with a median entrance to acarinarium, and narrowly excavated
clypeal apex. Length to apex of second tergite 10 mm.
HOLOTYPE, female, Atlantic Beach, Florida (A. T. Slosson). PARATYPE,
female, Florida. Type in U. S. National Museum.
Although the male is unknown, it should be easily recognized
by the deep apical incision and spine-like apical teeth of the
clypeus which are characteristic of the species. Also, it should
have the acarinarium entrance found only in vagus in North
THE FLORIDA ENTOMOLOGIST
Stenodynerus (Parancistrocerus) bicornis (Robertson)
Odynerus bicornis Robertson, 1901. Trans. Amer. Ent. Soc.
27: 196. Male, female, Inverness, Florida.
SPECIMENS STUDIED.-Florida: Inverness, Orlando.
Stenodynerus (Parancistrocerus) bifurcus Robertson
Odynerus bifurcus Robertson, 1901. Trans. Amer. Ent. Soc.
27: 196. Male, female, Inverness, Florida.
SPECIMENS STUDIED.--Florida: Inverness, Gainesville, Or-
lando, Tallahassee, Crescent City, Sanford, St. Johns River,
Cocoa, Plant City, Moore Haven; Georgia: Okefenokee Swamp.
Stenodynerus (Parancistrocerus) perennis anacardivora
Odynerus anacardivora Rohwer, 1915. Proc. U. S. Nat. Mus.
49: 241. Female, Miami, Florida.
SPECIMENS STUDIED.-Florida: Fort Myers, Long Key,
Gainesville, Maimi, Indian River, Englewood, Mayport, Jack-
sonville, Palm Beach, Enterprise, Orlando, Tallahassee, Fla-
mingo, Cocoa, Upper Matecumbe Key, Goulde, St. Petersburg;
Georgia: Atlanta; North Carolina: Raleigh; Louisiana: New
Stenodynerus (Parancistrocerus) histrio (Lepeletier)
Odynerus histrio Lepeletier, 1841. Hist. Nat. Ins. Hym. 2:
638. Male, "Carolina".
SPECIMENS STUDIED.-Florida: Indian River, Haulover, Au-
cilla River, Royal Palm Park; Georgia: Brunswick; Louisiana;
Virginia: Camp Peary; District of Columbia.
Stenodynerus (Parancistrocerus) fulvipes rufovestis
MALE.-Black, dull red and yellow. Clypeus yellow; Y-shaped inter-
antennal mark, mandible spot and lower orbit orange-yellow; apical bands
on tergites I and II and sternite II, spot on tegula, parategula, legs partly,
scape in front dull orange yellow. Dull red are: basal 4 flagellar segments
entirely, next 3 beneath, mandible tip, postocular spot, emarginate humeral
band, narrow hind pronotal margin, tegula mostly, spot beneath, band
across postscutellum, large lateral spot on tergite I attached to apical
band, legs mostly. Deep red are: propodeum, sternite I, tergite I before
summit ridge. Wings dusky with violet reflections. Length to apex of
second tergite 8 mm.
VOL. XXXI-No. 3
FEMALE.-Clypeus with a basal curved reddish mark, interantennal. spot
abbreviated, ocular dot and red mesonotal spot present. Length to apex of
second tergite 9.0 mm.
HOLOTYPE, male, Orlando, Florida, March, 1944 (R. and G. Bohart).
PARATYPES, 47 males and 13 females from the following Florida localities:
Orlando, Cocoa, Palatka, Upper and Lower Matecumbe Key, Key Largo,
Everglades, St. Petersburg, Indian River, Key West, Cedar Key, Fruit-
ville, Apalachicola, La Belle, Punta Rassa, and Arcadia. I have also seen
a female specimen from McClellanville, South Carolina. Paratypes were
collected from March to August. Type in U. S. National Museum.
Structurally rufovestis appears identical to fulvipes (Saus-
sure). It has interocellar tubercles, relatively narrow male
clypeus, broad but tapering parategulae, propodeum in a shelf
below postscutellum, prominent ridge across summit of tergite
I and no free spots on tergite II. It appears to be restricted
mainly to central and south Florida but intermediate specimens
are found occasionally as far north as Washington, D. C.
Stenodynerus (Parancistrocerus) saecularis rufulus
MALE.-Black, marked with orange yellow and reddish. Orange yellow
are: mandible mostly, clypeus, lower orbit, wedge-shaped interantennal
spot, scape in front, legs partly, apical bands on tergites I and II and
sternite II. Orange red are: scape behind, pedicel, flagellum beneath at
base, postocular spot, 2 humeral spots, tegula partly, spot beneath, para-
tegula, postscutellar band, propodeum partly, spot along summit, sternite
I. Wings brown stained, somewhat violaceous. Pubescence pale grey
to fulvous, mostly rather sparse but longer and more prominent than
usual; that on dorsum of thorax, near summit of tergite I and at basal
middle of sternite II as long as 1.5 ocellus diameters. Puncturation
moderately coarse, well spaced on clypeus; tergite I with a row of shallow
punctures following a well-defined ridge across summit. Vertex with
smooth area present near compound eye, clypeus angularly incised at apex;
parategula rather broad; interocellar area punctured, not raised above
ocelli which are large with a diameter about as great as length of pedicel;
propodeum with a weak shelf below postscutellum; tergite I nearly as
broad as II in top view; tergite II apically reflexed' about l1 ocellus
diameter; sternite II with a shallow basomedian crease. Length to apex
of second tergite 8.0 mm.
FEMALE.-Markings often more extensively orange red instead of orange
yellow. Clypeus with a curved basal mark of red or orange; ocular and
mesonotal dots present, spots sometimes present between ocelli and com-
pound eye; tergite IV sometimes banded; sternite II sometimes with
apicolateral spots instead of band. Vertex depression angled behind, as
broad as 2 ocellus diameters; ocelli smaller than in male, diameter of
hind ocellus 2/ pedicel length. Length to apex of second tergite 9.5 mm.
THE FLORIDA ENTOMOLOGIST
HOLOTYPE, male, Orlando, Florida, May 21, 1925 (0. C. McBride).
PARATYPES, 2 males and 8 females from the following Florida localities:
Waldo (R. H. Beamer, J. Nottingham), Jacksonville (W. H. Ashmead),
No Name Key (G. N. Collins), Dunnellon (D. E. Hardy), Davenport and
Wildwood (J. Nottingham), Homestead (J. C. Bradley), Tampa and
Miami. Type in U. S. National Museum.
A nearly mature male from Orlando, Florida, (D. J. Nichol-
son) bears the data "reared from oak galls on scrub oak."
The extensive reddish markings distinguish this subspecies
from typical saecularis Saussure which occurs along the eastern
seaboard from Georgia to New Jersey and in Texas.
INSECTICIDE STUDIES ON CHINESE CABBAGE FOR THE
CONTROL OF THE TURNIP APHID, Rhopalosiphum
pseudobrassicae (Davis) AND CERTAIN
FOLIAGE FEEDING LARVAE
NORMAN C. HAYSLIP
Associate Entomologist, Everglades Experiment Station, Belle Glade, Fla.
A number of serious insect pests attack Chinese cabbage
in the peat and muck soils of the Florida Everglades. Seldom
is this vegetable grown without moderate to severe infestations
of aphids, and several important leaf feeding larvae often attack
the crop. The habit of growth of the Chinese cabbage plant is
such as to make insect control difficult, especially after heading
begins. The tight fitting, upright, cupped leaves offer pro-
tection to insects from applications of spray materials. If in-
sects are present even in moderate numbers, many heads of
cabbage are not marketable, and a large number must be strip-
ped severely to remove the infested leaves. Since aphids con-
stitute the most serious insect pest of the crop in this area, an
experiment was conducted at the Everglades Experiment Station
for the purpose of testing some of the new insecticides for
their effectiveness against these pests, and to compare them with
standard aphicides. Cutworms, predominately the black cut-
worm, Agrotis ypsilon (Rott.); the fall armyworm, Laphygma
frugiperda (A. & S.) ; and the cabbage looper, Trichoplusia ni
(Hbn.) appeared in the plots and a record of the performance
of the treatments on these insects was obtained.
METHODS AND MATERIALS.-The plot area was plowed, disced,
leveled and mole drained. Soil reaction determinations showed
VOL. XXXI-No. 3
the need for sulfur, and an application of 750 pounds per acre
was broadcast with a mechanical distributor. One thousand
pounds per acre of an 0-12-16 commercial fertilizer with secon-
dary elements was applied at the same time and in the same
manner as the sulfur, and these materials were disced into the
soil 16 days before drilling the cabbage seed. The seed was
planted on November 14 with a mechanical seeder in rows
spaced 30 inches apart. Four 30 foot rows, separated from other
plots by 8 foot alleys parallel to the rows, and by 5 foot alleys
between plots perpendicular to the rows, made up each plot.
Two buffer rows were planted parallel to the plot rows at each
side of the plot area. Each treatment was replicated 5 times
in a randomized block design. The following treatments were
1. DDT 5 percent by weight of technical DDT dissolved in a refined
petroleum oil base.
2. DDT 25 percent emulsion-1 quart per 100 gallons water.
3. Benzene hexachloride 50 percent wettable containing 6 percent gamma
isomer-3 pounds per 100 gallons water.
4. Benzene hexachloride dust-1.5 percent gamma isomer, carrier inert.
5. Benezene hexachloride wettable-25 percent gamma isomer-1 pound
per 100 gallons water.
6. Hexaethyl tetraphosphate-50 percent-1 pint per 100 gallons water.
7. Parathion-15 percent wettable-1 pound per 100 gallons water.
8. Parathion-1 percent dust, carrier inert.
9. Nicotine sulphate-40 percent nicotine-1/2 pints per 100 gallons
10. Nicotine alkaloid-80 percent nicotine-1 pint per 5 gallons refined
petroleum oil base.
11. Pyrethrum (0.4 percent pyrethrins) plus Rotenone (2.5 percent ex-
tract) 1 pint per 100 gallons water.
12. Check, no treatment.
A commercial spreader-sticker was added to all water spray
materials. The sprays were applied at the rate of 150 to 200
gallons of diluted spray per acre with a power sprayer using
100 pounds pressure for the first 2 applications and 300 pounds
pressure for the third application. A 3 nozzle boom was used
for all treatments. Dust applications were made with a rotary
hand duster, at 3_ to 40 pounds of dust per acre. The 2 oil
based insecticides were applied at the rate of 11/2 to 2 gallons
per acre with a specially designed applicator constructed by
THE FLORIDA ENTOMOLOGIST
Mr. John W. Randolph, Agricultural Engineer, Everglades Ex-
periment Station. The dusts were applied in the early morning
when dew was on the plants and all other treatments were made
when the foliage was dry. Insecticide applications were made
on December 9, 16, and 30. The first application was made after
a large number of winged aphids had infested the plots. Cut-
worms and armyworms were abundant throughout this experi-
ment and a general application of poisoned bait was made
November 20. On November 21 and 29 about 25 pounds per
acre of 5 percent DDT dust was applied to the plants with a
rotary hand duster as a further measure of control of cutworms
and armyworms. Because of a moderate infestation of wire-
worms, about 40 pounds per acre of 5 percent chlordane dust
was applied between the rows and cultivated into the soil on
December 5. These general insecticide applications were neces-
sary to insure a stand of plants. Aphid counts were made at
intervals following each aphicide treatment, and a pre-treat-
ment count was made one day before the third treatment was
applied. One mature leaf from each of 25 plants taken at
random within each plot made up a plot sample. In order to
determine the effect of the aphicides upon cutworms, a count
of plants damaged by cutworms was made on January 5. Har-
vest records were obtained from a random sample of 10 heads
of cabbage cut from each plot 28 days after the last aphicide
treatment. Each cabbage was scored for aphid abundance and
extent of worm damage.
DISCUSSION OF RESULTS.-Aphids: A general infestation of
winged aphids migrated into the plot at about the time the
plants were thinned to a stand. Aphid collections were made
at the beginning of the experiment and again toward the end
of the test. These aphids were identified as the turnip aphid,
Rhopalosiphum pseudobrassicae (Davis). The infestation in
the untreated check increased steadily until a few days follow-
ing the last insecticide treatment. Table 1 contains data show-
ing this increase in aphid population. The infestation reached
its peak at about the time of the third insecticide treatment.
Parasitic fungi and lady beetles became well established by
this time and were later responsible for some reduction in the
All insecticide treatments were significantly better than
the unsprayed check on every date aphid counts were made,
with the exception of treatment number 1 which was no better
TABLE 1.-CONTROL OF THE TURNIP APHID, Rhopalosiphum pseudobrassicae (Davis), ON CHINESE CABBAGE, DATA SHOW-
ING APHID POPULATION AT INTERVALS FOLLOWING EACH INSECTICIDE APPLICATION.*
Number of Days
After 1st (Dec. 9)
Number of Days
After 2nd (Dec. 16)
1 1 3 I 6 1 3 | 6
1. 5 percent DDT (oil base) ...........................
2. 25 percent DDT emulsion ............................
3. Benzene hexachloride 6 percent gamma
isomer wettablee) .................. ............
4. Benzene hexachloride 1.5 percent gamma
isom er (dust) ...... ......... .... .......-.... .
5. Benzene hexachloride 25 percent gamma
isomer wettablee) ..........................
6. 50 percent Hexaethyl tetraphosphate ........
7. 15 percent Parathion wettablee) ..---.......
8. 1 percent Parathion (dust) .......................
9. 40 percent Nicotine sulphate .....................
10. 80 percent Nicotine alkaloid (oil base)......
11. Pyrethrins (0.4 percent); Rotenone
(2.5 percent) ..................... .................
12. Check, no treatment .....................................
Least significant difference (19:1) ...................
1 Day Before
3rd (Dec. 30)
* The number of aphids shown in this table is the total number of aphids per 125 mature leaves.
A 25 leaf sample from each replication was taken at random and the totals for the five applications are recorded.
** DDT emulsion was placed on this plot treatment by mistake, and no records were taken.
THE FLORIDA ENTOMOLOGIST
than the check one day before the third insecticide treatment
was applied. All formulations of parathion and benzene hexa-
chloride gave extremely low aphid counts with almost complete
eradication of aphids in the parathion dust and spray plots and
the benzene hexachloride (low gamma isomer) dust and benzene
hexachloride (high gamma isomer) spray. It is evident from
Table 1 that lower dosage rates would be necessary to bring
out the difference in effectiveness of benzene hexachloride and
parathion. In the case of the 2 counts made 6 days following
the first and second aphicide applications and the precount made
13 days following the second treatment, parathion and benzene
hexachloride were outstandingly superior to all other materials.
It will be noted in Table 1, that following the first treatment
of insecticides, both DDT and nicotine applied in an oil base
at about 11/2 to 2 gallons per acre of diluted spray gave control
equal to that obtained with a power sprayer using a water
base and applied at about 150 gallons per acre of the diluted
spray, despite the fact that less killing agent per acre was ap-
plied in the oil based sprays. In subsequent applications the
water based sprays gave better control than did the concentrated
oil based insecticides. This difference in control probably was
due to the inability to secure adequate coverage with the oil-
insecticide applicator after the plants became large. Further
studies are underway in an effort to develop a more effective
spray applicator for concentrated solutions.
Table 2 contains data on aphid abundance at harvest time.
These records were obtained 28 days after the last insecticide
application was made. A sample of 10 cabbages was collected
from each plot and each cabbage was scored as shown below
the table. The total score for the 10 heads of cabbage is re-
corded. Benzene hexachloride and parathion were far superior
to any other material used and the differences were highly sig-
nificant. Nicotine sulphate spray was lower in aphid abund-
ance than were any of the treatments except the parathion
and benzene hexachloride. The pyrethrum-rotenone spray was
inferior to the nicotine sulphate, parathion and benzene hexa-
chloride treatments, but was definitely superior to the nicotine
alkaloid-oil, hexaethyl tetraphosphate, DDT emulsion and DDT-
oil treatments. The DDT emulsion and hexaethyl tetraphos-
phate were superior to the untreated check, but did not approach
commercial control. Nicotine alkaloid-oil and the DDT oil
treatments were no better than the untreated check.
Table 2.-CHINESE CABBAGE HARVEST RECORD SHOWING EFFECT OF INSECTICIDES ON APHID ABUNDANCE
AND AMOUNT OF WORM DAMAGE.*
Amount Aphid Infestation Amount Worm Damage
Treatment Block I Total Block I Total
A B C D E | Score A B C D EJ Score
1. DDT- 5 percent in oil (2 treatments)
DDT--25 percent emulsion (1 treatment)...
2. DDT-25 percent emulsion .....................
3. Benzene hexachloride wettablee)
6 percent gamma isomer ............................
4. Benzene hexachloride (dust)
1.5 percent gamma isomer ..............--.......
5. Benzene hexachloride wettablee)
25 percent gamma isomer ........................
6. Hexaethyl tetraphosphate-50 percent ---.....
7. Parathion-15 percent wettable ....................
8. Parathion-1 percent dust .. --.................
9. Nicotine sulphate-40 percent nicotine ........
10. Nicotine alkaloid-80 percent nicotine ........
11. Pyrethrins (0.4 percent)
Rotenone (2.5 percent) ...............................
12. Check, untreated ---------------....... .......
Least significant difference (19:1) ......................
0 1 0 1 1
0 0 1 0 0
1 1 0 1 2
1 0 1 1 2
* A scoring system was used as follows:
-28 days before harvest
Ten heads of cabbage per plot were taken for the above scoring.
Worms responsible for damage included cutworms, fall armyworms, cabbage looper.
Three insecticide applications were made as follows: 1st-49 days before harvest 2nd-42 days before harvest 3rd-
THE FLORIDA ENTOMOLOGIST
Cutworms: In spite of one application of poisoned bait and
2 dust applications of 5 percent DDT and one of 5 percent
chlordane, a considerable number of cutworms remained in the
plots beneath the large cabbage plants. Since these insecticide
treatments for armyworms and cutworms were general over
the entire experiment, an evaluation of the comparative effective-
ness of the aphicides against cutworms was possible. On
January 5, counts of plants damaged by cutworms were made.
Parathion, DDT and benzene hexachloride gave lower counts of
damaged plants than the other treatments or the check. The
remaining treatments were ineffective against -cutworms, with
no decrease in damaged plants. Table 2 contains harvest data
showing the effect of the insecticide treatments upon the amount
of damage caused by cutworms (mostly the black cutworm
Agrotis ypsilon (Rott.), the fall armyworm, and the cabbage
looper. No attempt was made to determine the effect of the
treatments on individual species and the data therefore are
indicative only of a general larvacide effect on Chinese cabbage
in the presence of the above insects. All treatments except
hexaethyl tetraphosphate were superior to the check. The
DDT, benzene hexachloride and parathion treatments gave good
control and were outstandingly better than the remaining treat-
ments and the check. There was no difference between the re-
sults obtained with nicotine sulphate, nicotine alkaloid and
pyrethrum-rotenone, but these treatments were all superior to
SUMMARY.-An experiment on Chinese cabbage designed
primarily for the control of aphids and conducted on organic
soil at Belle Glade, Florida, during the winter, 1947-48, is re-
ported. The species of aphid encountered was Rhopalosiphum
pseudobrassicae (Davis). Cutworms, armyworms, and cabbage
loopers also were present in the plots and the effectiveness of
the treatment against these insects is reported.
The 12 treatments were replicated 5 times in randomized
blocks and included several of the new insecticides in addition
to standard aphicides. Two materials were used in oil bases
and applied at low dosage rates with a special oil applicator
under development at the Everglades Experiment Station. Data
obtained from periodical aphid counts and harvest records are
included in the tables.
Parathion dust and spray and benezene hexachloride dust
and spray were found to be outstanding aphicides and gave ex-
VOL. XXXI-No. 3
cellent control. Harvest records showed nicotine sulphate and
pyrethrum-rotenone spray to be fairly effective, but none of the
other treatments gave satisfactory control. DDT, parathion
and benzene hexachloride treatments gave excellent control of
the worms. All other treatments except hexaethyl tetraphos-
phate gave a reduction in worm damage, but none of these treat-
ments gave satisfactory commercial control.
The treatments in this experiment did not appear to impart
any taste to the cabbage, and no injury was noted except that
very slight injury occurred on a few plants where benzene
hexachloride dust was applied.
The writer is indebted to Dr. A. N. Tissot, Entomologist, Agricultural
Experiment Station, Gainesville, Flori'da, for his cooperation in determining
the aphid species under study, and for reviewing the manuscript.
Appreciation is due Mr. Charles E. Seiler, Field Assistant for his valu-
able assistance in handling many of the details of this experiment.
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