Title: Florida Entomologist
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Title: Florida Entomologist
Physical Description: Serial
Creator: Florida Entomological Society
Publisher: Florida Entomological Society
Place of Publication: Winter Haven, Fla.
Publication Date: 1941
Copyright Date: 1917
 Subjects
Subject: Florida Entomological Society
Entomology -- Periodicals
Insects -- Florida
Insects -- Florida -- Periodicals
Insects -- Periodicals
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General Note: Eigenfactor: Florida Entomologist: http://www.bioone.org/doi/full/10.1653/024.092.0401
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Volume ID: VID00264
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Florida Entomologist
Official Organ of the Florida Entomological Society

VOL. XXIV FEBRUARY, 1941 No. 1

NOTES ON THE BIOLOGY OF THE FLORIDA RED SCALE
(Chrysomphalus aonidum (L.))
WILLIS MATHIS1
U. S. Department of Agriculture
Bureau of Entomology and Plant Quarantine
St. Lucie, Fla.
The Florida red scale was first noticed in Florida in 1879
on a sour-orange tree imported from Cuba and planted near
Orlando.2 Although it has been present in citrus groves here
for 60 years and has been one of the most destructive scales,
second only to the purple scale (Lepidosaphes beckii (Newm.))
in damage to trees and fruits, very little has.been published on
the species. Work on its biology and on control was resumed
as a definite work project at the Orlando laboratory in 1936
and is being continued in the new laboratory at St. Lucie.
LIFE'HISTORY
METHODS OF STUDY: For the study of the life history of the
Florida red scale, in 1939 orange and grapefruit trees that had
very few scales on them were selected and tagged for identifica-
tion. Artificial infestations were obtained by gathering leaves
from trees that had heavy infestations and attaching them to
the leaves or fruits of the selected trees. The infested leaves
were clipped to both the upper and lower surfaces of leaves to
be infested, and were fastened to fruits by means of rubber
bands. The infested leaves were usually left on for two days
so that the crawlers could crawl from under the scale coverings
of the females and onto the clean leaf or fruit. After the old
leaves were removed, the crawlers that had settled were identi-
fied by India ink numbers placed on the leaf or fruit. Each
individual that settled was examined every two days when
possible, and its stage was recorded. New infestations were
'For much valuable advice and supervision the writer is greatly in-
debted to Herbert Spencer and Max R. Osburn.
'Comstock, John Henry. 1916. Reports on scale insects. N. Y.
(Cornell) Agr. Expt. Sta. Bul. 372: 276-603, illus.









THE FLORIDA ENTOMOLOGIST


made the first of each month to determine the influence of the
seasons on the time spent in each stage.
The studies were made under as nearly natural conditions
as possible. The trees selected were part of a grove and were
not artificially protected in any way. The crawlers and marked
scales from the artificial infestations were therefore exposed
to the weather, predacious insects, and fungi as are the scale
insects in any grove. The only difference between the artificial
infestations and the natural infestations was the placing of the
crawlers on the leaves or fruits and the marking. Supple-
mentary work on some crawlers on potted plants was done in
the screened insectary.
NATURAL MORTALITY: From March through September, 820
scales were under observation. Of that number, 256, or only
31 percent, reached the second larval stage and only 143, or
17.5 percent, reached the adult stage. Of these adults, 51 were
females and 92 were males. Only 10 of the females were able
to survive long enough to produce young.
Weather and insect enemies destroyed many of the scales
marked for observation. A tropical storm on August 11, with
60-mile gusts of wind and 2 inches of rain in 24 hours, killed
90 percent of a lot of 178 that had settled and had been marked
the week before. One trashbug (a hermerobiid or chrysopid)
was seen destroying young scales, and the torn coverings of
others were apparently the work of predacious enemies. In-
ternal parasites also destroyed some, as indicated by the holes
left in the scale coverings. Less than 1 percent of the scales
studied showed any evidence of entomogenous fungi.
THE FIRST-STAGE LARVAE: Observations were made during
July and August to determine the time between hatching and
settling of the crawlers, the time required to reach the white-
cap stage, and how long they remained in this stage. The white-
cap stage is considered to cover the period from the time the
young scale becomes completely covered with the white, waxy
substance secreted from the body until the outline of the true
scale can be distinguished.
For this experiment two small seedling orange trees were
planted in boxes and placed in the screened insectary. Two
methods were used for infesting the leaves with crawlers. By
the first method the scales of the ovipositing females were lifted
and the leaf to which they were attached was held over the leaf
to be infested and gently tapped to dislodge the crawlers and









VOL. XXIV-No. 1


allow them to fall on the clean leaf. By the second method the
scale coverings were lifted in the same way and the crawlers
were transferred with a fine camel's-hair brush. All the crawl-
ers on the new leaf that did not move were then removed, and
the others were watched constantly until they settled. As they
settled they were numbered with India ink, and then were
examined every few minutes until the first-ring stage was
reached, that is, until the waxy covering began to expand later-
ally, forming a ring around the central nipple.
After the crawlers were placed, they generally went over
both the upper and lower surfaces of the leaves, and selected
a small area over which they moved carefully until they found
the exact place, usually a small depression. When they were
settled they began "rounding" almost immediately. The first
noticeable change was the disappearance of the antennae and
legs. They were apparently drawn under the body, and then a
white, waxy substance was thrown up over the body.
Eighteen crawlers were studied. The average time after the
crawler was placed on the leaf before it settled was 1 hour and
43 minutes, and 1 hour and 28 minutes for the settled crawler
to reach the white-cap stage. The average time spent in this
stage was 20 hours and 45 minutes.
The longest period spent in the first larval stage was during
March. The average was 19 days, with a range of 17 to 22 days.
In June the average was only 10 days, with a range of 7 to 16
days. The average for the 7-month period was 14 days.
With a view of determining how far crawlers would travel
with no hindrance, records were made of the distance traveled
on smooth paper for 2-hour periods. The crawlers were placed
on the paper, and their movements were traced and measured
with a map measure. Six crawlers were observed, and the
average distance traveled was 38 inches, with a range of 19 to
59 inches. The average temperature was 86.50 F. and the rela-
tive humidity 67 percent.
Observations were also made of five crawlers on mature
grapefruit until they settled, and their movements were traced
and measured. The average distance was 4 inches, with a range
of 1.5 to 9 inches. The average temperature was 77' F. and
the relative humidity 84 percent.
To determine what percentage of the crawlers settled under
natural conditions, 77 crawlers were placed on orange leaves
and were left for several hours. Only 39 were able to settle.









THE FLORIDA ENTOMOLOGIST


This points to a 50-percent mortality during favorable weather.
In stormy weather this would undoubtedly be greater.
THE SECOND-STAGE LARVAE: The time spent in the second
larval stage has been determined separately for males and fe-
males, because of difference in lengths of time for development.
In this stage the males can be distinguished from the females
by the color and shape of the outer covering. The male is darker,
slightly longer than wide, and more convex than the female;
the female has a reddish brown color which gradually turns
darker with age, and is flatter than the male. The longest time
spent in this stage was in March, when 14 days were required
by the male and 23 days by the female. The shortest time spent
by the male in this stage was in August, when only 4 days were
required. For the female the shortest time was in June, when
only 10 days were required. The average for the entire period
was 8 days for the male and 15 days for the female.
LIFE CYCLE: The length of time from crawler to oviposition
ranged from 52 days when settling occurred in August to 95
days when it occurred in February, with an average of 74 days
for all ovipositing females.
A generation, from crawler to crawler, required less than
60 days during the summer.
The span of life for the ovipositing females from crawler to
death ranged from 56 days in August to 110 days in January,
with an average of 84 days.
THE ADULT FEMALE: When a female scale reached the adult
stage, all other scales were removed from the leaf and it was
watched closely for the first young. As the young appeared, they
were removed so that they would not be counted twice. The
most complete record of the number of young that a female pro-
duced is from a female that settled June 10. The first young
were noticed 59 days after infestation, and the female produced
an estimated 102 crawlers in 41 days, of which 51 were able to
settle and start development. The full span of life for this scale
was 100 days. The average time spent in the adult stage by the
females that oviposited was 58 days, with a range of 28 to 80
days.
SEASONAL HISTORY
Work on the seasonal history of this scale was carried on
during 1937 and 1938. Leaves were gathered at regular inter-
vals and the scales were examined under binocular microscopes.
A percentage method of recording the stages found was used for









VOL. XXIV-No. 1


this work. The numbers of scales examined each time were
counted and classified as eggs, crawling young, males, and fe-
males, and were further subdivided as to age where it was
possible. The results show that active crawlers can be found
in any month of the year and that reproduction of the species
is continuous. Reproduction has two peaks each year, the first
during March, April, and May, and the second during July,
August, and September. The latter peak is responsible for the
young that heavily infest the fruit. Weather conditions are
thought to be more favorable for reproduction during these
months. SUMMARY
SUMMARY
The life span of the female has been found to be about 100
days during the summer months, young being produced within
52 days. The natural mortality of the scale is very heavy, only
about 17.5 percent reaching maturity during summer. The
most rapid period of growth was found to be in June and the
slowest observed was in March. Crawlers may be found in any
month of the year, with two distinct reproductive peaks.

BOUNCING BUDS
All entomologists are acquainted with the Mexican jumping
beans, but the writer never seems to remember of having heard
of jumping buds. Late in February, 1940, Doctor W. A. Murrill
was making a comparative study of the buds of plum trees. In
the course of this investigation he pulled the buds off of the
branches of two Chickasaw plums and placed them in separate
piles. To his surprise they did not stay separated, but began
to jump about, some covering as much as an inch or two in one
jump. This was disconcerting to the eminent botanist who
wanted to keep the buds separate. He investigated the cause
of this untoward behavior and found that the buds were in-
habited by the larvae of weevils. He turned them over to the
writer who in company with Doctor Murrill visited the plum
thicket and collected more of these plum buds. A considerable
percentage of the buds were found to be infested. They dropped
from the trees without opening and the larvae pupated in the
ground. Some that were brought to the laboratory and placed
on moist earth on March 4th emerged on March 23rd and 27th.
They were identified by Mr. L. S. Buchanan of the National
Museum as Anthonomopsis mixus Lec. They were highly
parasitized by a Calcidoid identified by A. B. Hahan, also of
the National Museum, as a species of Zotropis. No opportunity
was given to obtain another generation since by the time these
weevils emerged the plum blossoms were gone. There can be
but one generation a year in plum buds.
J. R. WATSON









Uhe

FLORIDA ENTOMOLOGIST
Official Organ of the Florida Entomological Society
Gainesville, Florida

VOL. XXIV FEBRUARY, 1941 No. 1

J. R. WATSON, Gainesville....---......-...---.................. ...--- Editor
E. W. BERGER, Gainesville....--------................... ..Associate Editor
J. W. WILSON, Belle Glade...............---...............Business Manager
Issued once every three months. Free to all members of the
Society.
Subscription price to non-members is $1.00 per year in ad-
vance; 35 cents per copy.


THE SMALL FIRE ANT Wasmannia IN CITRUS GROVES-
A PRELIMINARY REPORT
HERBERT SPENCER
Bureau of Entomology and Plant Quarantine
St. Lucie, Fla.
During 1935 and 1936 reports began to come in of annoyance
to citrus fruit pickers by small stinging ants. These complaints
have increased in number since then, and late this spring there
were at least two instances on the East Coast of Florida where
picking crews had literally been driven from their work by
these ants.
The species concerned, Wasmannia auropunctata (Roger),
was described in 1863 in a German publication (1)1. In 1929
M. R. Smith reported its presence in the United States from
specimens sent to him from Miami, Fla. (3). Later in the
same year, W. M. Wheeler (4), in commenting on this report,
said that in 1924 he had received specimens from the Fairchild
place in Coconut Grove, Miami, with the information that the
stings of the species were painful. He stated that Wasmannia
is a very common ant throughout Central America, northern
South America, the West Indies, and warmer portions of Mex-
ico, and that in Puerto Rico it is a pest in coffee plantations
and coffee pickers are seriously annoyed by it. By that time
it had also become well established in the Kew Gardens in
England.

'Numbers in italics in parentheses refer to Literature Cited, page 14.









VOL. XXIV-No. 1


In Puerto Rico the ant Wasmannia is called the "albayalde".
During 1935 and 1936 the "albayalde" was studied there by
M. R. Smith (6)2 in connection with coffee insects. He found
these ants feeding on honeydew produced by the hemispherical
scale (Saissetia hemisphaerica (Targ.)), the green scale
(Coccus viridis (Green)), the aphids Toxoptera aurantiae
Boyer, Sipha flava (Forbes), and Pentalonia nigronervosa
Coq., and the mealybugs Pseudococcus brevipes (Ckll.), P. sac-
chari (Ckll.) and P. virgatus (Ckll.). He quoted a statement
by another worker, R. H. Van Zwaluwenberg, that the "albay-
alde" often kills out or displaces colonies of the ants called
"hormiguilla" (Myrmelachista ramulorum Whlr.) in coffee
groves.
RECORDS FOR FLORIDA
In time that could be spared from other work a survey of
Florida has been made and infestations of Wasmannia have been
found in citrus groves or nurseries in the following places:
Florida East Coast Central Florida Florida West Coast
Homestead St. Cloud Naples
Perrine Orlando Arcadia
Coconut Grove Winter Park
Miami Apopka
Miami Beach Auburndale
Fort Lauderdale
Fort Pierce
Cocoa
New Smyrna
It is probable that the ant is present in many other places in
the lower two-thirds of Florida, but even with the records we
now have, we can say that there are many small infestations
well scattered through that part of the State.

DISPERSAL
It is probable that these local spot infestations will enlarge
slowly each year unless checked. The rate of spread in one city
infestation was about 50 feet in one year, and this was by en-
largement of the colony's ground network. Although the queens
have wings, no flight has been observed, and in the formicary
there is no tendency of the queens to fly, but they crawl about
wherever the workers go. In a Miami nursery a thriving colony,

'Also unpublished reports on investigations of coffee insects, 1935-36,
by M. R. Smith, Bureau of Entomology and Plant Quarantine, U. S. De-
partment of Agriculture.









THE FLORIDA ENTOMOLOGIST


with queens and brood, was found 6 feet above ground level in
the V-shaped angles on a coconut palm leaf where the green leaf
parts are attached to the leaf stem. There is much danger of
artificial spread from palm or citrus nurseries, as the ants nest
around the bases of the trunks and even under leaf bases and
in crevices and depressions located well above ground, and many
of these nursery plants are transplanted in a ball of soil in
which the ants may be nesting.

DESCRIPTION
Wasmannia is a small golden-brown ant, one of the smallest
we have in Florida. The workers may be distinguished easily
from other grove ants by their small size, their distinctive color,
and especially by their slow, deliberate rate of movement, in
broad trails up trunks and branches to the leaves. According
to M. R. Smith,3 workers of Wasmannia may be separated from
those of the fire ant (Solenopsis geminata (F.)) by the antennal
club being 3-jointed instead of 2-jointed, by the presence of
two spines on the posterior dorsal part of the thorax, and by
the absence of teeth on the clypeus. Usually, after a few en-
counters, it is not necessary to see if the suspected small ant
stings severely. This is, however, another sure means of identi-
fication, since no other small grove ant stings as severely as
the Wasmannia. The queens are large compared with the work-
ers, being one-fourth inch long.

NESTING HABITS
Most ants dig definite nest tunnels into the ground, and
these may have one or several entrances. The small fire ant is
unusual in its nesting habits, as it has no definite nests. It may
live between tree trunk and soil at the surface level or just
below; often a few queens, brood, and worker masses take
possession of holes and decayed places in the tree trunks several
feet above the ground. Another favorite place is under leaf
bases of palms or palmettos in natural growth adjacent to the
groves. Between the trees flat pieces of wood or stones or
partially decayed masses of cover crops may be nesting places,
and a heavily infested uncultivated grove soon becomes one huge
nest network, with foci of queens and brood every 6 or 8 inches
and trails of workers connecting these reproduction centers.
The presence of moisture and slight shelter for the queens and

'Personal communication.








VOL. XXIV-No. 1


brood seem to be the only essentials for nesting, and it is seldom
that the ants go deeply into the ground for these.

NATURAL FOOD
Honeydew from insects is the most important food of Was-
mannia in Florida citrus groves. In the spring the usual out-
break of the green citrus aphid (Aphis spiraecola Patch) curls
the new-growth terminals and provides an abundance of honey-
dew. The tiny ants may be found in the curled leaves attending
the aphids and returning down their trails with distended abdo-
mens. Aphis gossypii Glover and Toxoptera aurantiae (Boyer)
are also visited for food. The citrus whitefly (Dialeurodes citri
(Ashm.)), the cloudy-winged whitefly (D. citrifolii (Morg.)),
and the woolly whitefly (Aleurothrixus howardii (Quaint.))
also produce honeydew. The honeydew from the first two drips
down on leaves below the ones infested, and the ants take up
the sweet material there, rather than from the insect bodies.
The cottony coverings over the woolly whitefly larvae catch some
of the honeydew, and the ants crawl over the groups of larvae
to take up the food. As the season advances, aphids become
fewer and whiteflies more abundant; then soft scales appear,
such as the green scale, the Florida wax scale (Ceroplastes flor-
idensis Comst.), and the cottony cushion scale (Icerya purchase
Mask.). These furnish food, too. The citrus mealybug (Pseu-
dococcus citri (Risso)) is especially abundant at times in grape-
fruit trees, and it furnishes much honeydew during an out-
break. In Florida there is seldom a time during the year when
honeydew-producing insects are completely absent.
In addition to these natural sources of food, the ants have
been observed feeding on carcasses of land crabs and small ani-
mals, and on dead insects. They also congregate under ripe
orange and avocado fruits that have broken open in falling to
the ground and eat the sweet juices or oils.

OTHER FOODS
Feeding tests made in groves and in a formicary have demon-
strated that the small fire ants will eat dry cane sugar, cane
sirups, and other sweet sirups, but they show a special fondness
for cooked fat meats, such as crisp bacon or fat beef, and also
for vegetable oils, such as olive oil and the cottonseed oil from
cans of cheap sardines. Milk may be eaten to some extent,
but the ants will leave it for sirups or fats.








THE FLORIDA ENTOMOLOGIST


Wasmannia is a serious problem in households near outdoor
infestations; it contaminates foods, is attracted to dirty and
sweaty work clothing, and even infests beds and stings severely
when rolled upon or touched. The problem of Wasmannia as
a household pest is under investigation by the Division of Insects
Affecting Man and Animals of the Bureau of Entomology and
Plant Quarantine, under the local leadership of W. V. King.
STINGING HABITS
Wasmannia does not sting readily. Individuals may wander
about over the uncovered skin for some time and cause no incon-
venience. They may be made to sting by pressing them down
to a tender spot of skin. In the grove they are all over the
leaves, eating honeydew, and when the pickers clip fruits, some
of the ants are dislodged and crawl about over the clothes.
Sooner or later they get between collar-band and neck, or under
the shirt or belt, or even between socks and ankles, and then,
when pressed, they sting sharply and severely. A single ant
may sting three or four times before it can be dislodged. Each
stung place gets red and swells, and finally a spot larger than
a silver dollar is affected. It may become whiter than the normal
skin, or redder. For some people a few stings give only slight
passing discomfort, but for others the sting lasts for three days,
aching painfully at first, and later itching intensely by spells.
If stings are numerous, say a dozen or two within a short time,
the victim gets pale and becomes "shaky" and unnerved, and
when a picker reaches this stage he quits work. Premiums have
to be paid in wages now to get picking done in some of the
groves having fire-ant infestations.
RELATION TO OTHER ANTS AND TO BENEFICIAL INSECTS
Wasmannia is more deliberate and much slower in its move-
ments than other ants infesting citrus groves, and has not been
observed chasing them or fighting other species. It probably
could not catch them. Ants which often visit the same food
plants around the edge of a nest network seldom can be found
feeding on the same leaves with the small fire ants. Anywhere
within the network of a heavy infestation other ant species are
conspicuous by their absence. Whether the other ants are put
to death by Wasmannia, or are repelled by the odors of that
species, or are starved out, is not clear at present. But like the
Argentine ant, Iridomyrmex humilis Mayr., the Wasmannia pre-
vails over other species.








VOL. XXIV-No. 1


The small fire ants do not prevent ladybeetles, such as the
vedalia (Rodolia cardinalis (Muls.)), from breeding and prey-
ing on host insects; the ants and ladybeetles have been found on
the same host several times. But it seems that infestations of
the cottony cushion scale thrive unusually well in ant-infested
groves in spite of the vedalias. Usually, with no fire ants,
vedalias clean up such a scale infestation quickly and completely.
Wasmannia workers have been observed carrying very young
cottony-cushion scales in numbers down their trails toward the
ground nests. It is almost certain that they deliberately spread
this insect from branch to branch and from tree to tree.

CONTROL EXPERIMENTS
(1) DESTRUCTION OF NESTS.-Some species of ants may be
controlled by the introduction into the nest of a fumigant such
as carbon disulfide or hydrogen cyanide. This is hardly possible
with Wasmannia, because of the character of the nest network,
which covers the ground and even extends up into the trees.
Without doubt, harrowing or shallow cultivation of a grove
would limit the suitable nesting spots to undisturbed ground
around the trees and would help control the ant and slow up
its spread into uninfested areas. However, there are large
districts in the State where such cultivation is not practiced.
To reduce the number of nesting places above ground, old leaf
bases should be removed from palms, and wounds and rotten
places in citrus trees should be cleaned out and treated.
(2) BARRIER BANDS.-For temporary protection of the pick-
ers and to cut the ants off from their food in the trees, a barrier
which is safe for the trees yet effective against Wasmannia
would be very useful. In preliminary trials, whitewash con-
taining crude carbolic acid and whitewash with bichloride of
mercury were ineffective, as they broke up the ant trails on the
tree trunks for only a few hours. A home-made sticky band,
composed of rosin two parts and castor oil one part by weight,
heated until homogeneous (5) was quite effective as long as
tree branches did not touch the ground or weeds touch the tree.
Citrus trees banded with a 2-inch ring of this mucilage soon
had a red ring of ants above the band from up in the tree and
another below, trying to get past the band. Eventually the ants
above the band dropped off, one by one, and the top of the tree
became free of ants. However, before this banding can be
recommended it must be tried out on a larger scale and its safety








THE FLORIDA ENTOMOLOGIST


to the trees demonstrated with all principal varieties and in all
types of weather.
(3) PROTECTION OF PICKERS.-To lessen the stinging of
pickers and of men who prune the trees, some growers try to
do the work on cold days, when the ants are not active. But
when the ants become more widely distributed, the few cold
days that occur will not be enough to do a fraction of the pick-
ing, even of those varieties which ripen during cold weather.
Some growers provide pyrethrum fly spray, and cloths sprayed
with this and tied around the neck repel some of the ants.
Elimination or reduction of the ants would be far better pro-
tection than either of these expedients.
(4) POISONED BAITs.-Seventeen different poisoned baits
have had preliminary trials and three have been used in large-
scale grove experiments on control. Baits with sodium arsenite
or tartar emetic as the poison are eaten greedily for several
days, but after that the ants go back to their natural food, honey-
dew. Many of the ants drown in the liquid baits, and the pres-
ence of these dead individuals in the liquid probably is one factor
that causes the ants to leave the bait. To avoid this, 1 percent
of agar by weight was incorporated in two formulas, and this
gave a semisolid bait that the ants ate longer; but still, after
a time, they went back to their honeydew diet. A bait made up
like the Argentine ant sirup (2), but containing tartar emetic
instead of sodium arsenite, is taken readily by the ants and is
promising. It would be favored by growers who are opposed to
placing arsenic near their trees. When derris or pyrethrum
was used as poison in baits the ants were definitely repelled
and plugged up the holes in the bait cans with mud.
In a citrus grove near Fort Pierce bait cans have been hang-
ing on 100 tree trunks for two years, and from time to time fresh
Argentine-ant bait has been added. The trees have been sprayed
regularly for control of scale insects, whiteflies, and rust mites,
and this has restricted somewhat the natural food that has been
available. A "high water" during this time, lasting only a day
or so, drowned many of the ants between the tree rows. This
high water, the spraying for insect control, and the ant bait,
working together, have reduced the number of ants greatly, so
that there was no great inconvenience to pickers of the last crop.
However, a few of the ants can still be found, and eradication
cannot be claimed.









VOL. XXIV-No. 1


A heavily infested and neglected citrus nursery at New
Smyrna has also had bait cans of Argentine-ant bait for two
years. When first seen, soft scale, whiteflies, and aphids were
very abundant, and the ants were thriving. The second year
a thorough spraying with oil emulsion reduced the natural food
supply and thus forced the ants to take the bait, and they were
reduced to about one quarter the number present the previous
year.
It is very clear from the work so far that poisoned baits
can be fully effective only when the natural food supply is cut
off. This might be accomplished by the use of barriers around
tree trunks, by baiting during the winter months when natural
food is scarce, or by thorough spraying to reduce the number
of honeydew producers.

ACKNOWLEDGMENTS
In the course of the survey and experimental work on Was-
mannia, help has been given by many, and among these special
mention must be made of W. V. King, Max R. Osburn, J. A.
Fluno, Willis Mathis, Norman G. Platts, John R. Springer, and
I. C. Clinton. Identifications of ant species have been made by
C. F. W. Muesebeck, Wm. M. Mann, and M. R. Smith. Among
experiment station and extension workers, especial interest has
been shown by Director Wilmon Newell, J. R. Watson, A. F.
Camp, W. L. Thompson, and county agents J. R. Gunn and
Thomas L. Cain, Jr.
SUMMARY
The small fire ant (Wasmannia auropunctata (Roger)) has
interfered with picking and pruning operations in infested citrus
groves by stinging workers severely. A survey has disclosed a
number of infestation spots of limited area in the middle and
lower East Coast section of Florida, in central Florida, and on
the lower West Coast of the State. Normally, the ants feed on
honeydew from scale insects, whiteflies, mealybugs, and aphids,
which attack citrus trees, and also eat dead animals and insects,
and juices from fallen fruits. They nest on the ground under
slight protection, and in trees; heavily infested groves contain
a vast network of scattered breeding foci with interconnecting
trails which extend up tree trunks and branches to the leaves,
where the honeydew is obtained.
Preliminary work on control indicates the advisability of
reducing natural food supplies by thorough spraying for control









THE FLORIDA ENTOMOLOGIST


of honeydew producers. Banding of tree trunks may bar the
ants from access to trees and lessen the number of stings for
fruit pickers. The use of a can of Argentine ant bait on each
tree trunk has reduced the numbers of ants in groves to levels
at which pickers are not seriously inconvenienced, but, even with
two years of baiting, complete eradication has not yet been
attained.
LITERATURE CITED
1. ROGER, JULIUS. 1863. Die neu aufgeftihrten Gattungen und Arten
meines Formiciden-Verzeichnisses. Berl. Ent. Zeitschr. 7: 131-214.
Berlin.
2. BARBER, E. R. 1920 (revised 1925). The Argentine Ant as a House-
hold Pest. U. S. Dept. Agr. Farmers' Bull. 1101.
3. SMITH, M. R. 1929. Two Introduced Ants Not Previously Known to
Occur in the United States. Jour. Econ. Ent. 22 (1): 241-243.
Geneva, N. Y.
4. WHEELER, W. M. 1929. Two Neotropical Ants Established in the
United States. Psyche 36 (2) : 89-90.
5. DUNHAM, GEORGE C. 1930. Military Preventive Medicine. U. S.
Army Medical Bul. 23, 1,051 pages (see page 740). Carlisle Bar-
racks, Pa.
6. SMITH, M. R. 1936. The Ants of Puerto Rico. Jour. Agr. Univ.
Puerto Rico 20 (4) : 819-875.






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VOL. XXIV-No. 1


NOTES ON THE BIOLOGY OF THE FIRE ANT Solenopsis
geminata (F.) IN FLORIDA AND GEORGIA
BERNARD V. TRAVIS1
Division of Insects Affecting Man and Animals
Bureau of Entomology and Plant Quarantine
United States Department of Agriculture
The fire ants comprise a large group of ants belonging to
the genus Solenopsis, many of which are of considerable eco-
nomic importance (Stoddard, 1931, 1932-39; Clark, 1931; Gor-
such, 1934; Smith, 1936; Mallis, 1938; Travis, 1938, 1938a;
Emlen, 1938; Eagleson, 1940). In this report are included
observations on Solenopsis geminata (F.) that were made dur-
ing 1935 to 1939 in the shooting preserve sections of northern
Florida and southern Georgia.
NEST.-The mound of this ant is an irregularly shaped, high
pile of earth formed as a dump heap of soil carried from the
underground tunnels. Some of the larger heaps may contain
as much as 2 pecks of soil, and are invariably constructed around
some clump of vegetation. In the areas studied these heaps are
typically associated with broom-sedge, Andropogon virginicus L.
The exit tunnels of the mounds seem to have no characteristic
locations, and during periods of drought they are loosely plugged
with soil particles and bits of plant debris.
The mound itself is a maze of flattened chambers and tunnels,
some of which extend laterally from 6 inches to over 100 feet.
These are seldom found below 3 inches under the surface of
the ground. Flat storage and refuse chambers are frequently
built in these passageways. When a lateral channel extends
into a clump of broom-sedge, a small network of galleries is
formed that appears to be a secondary colony location. The
vertical tunnels, which are found as deep as 6 feet in clay and
deeper in sandy soils, usually have short and enlarged lateral
branches.
There seems to be little soil preference, for nests occur in
sterile sand or in heavy clay soils. Colonies may also be found
on dry ridges or in swampy areas. Ordinarily, however, there
are fewer nests in the heavily shaded areas than in the more
open situations.

'The identifications of insects in this report were made in the Division
of Insect Identification of the Bureau of Entomology and Plant Quarantine;
the ants by M. R. Smith, the Coleoptera by E. A. Chapin, the Orthoptera
by A. B. Gurney, the mites by H. E. Ewing, and the mealybugs by H.
Morrison.








THE FLORIDA ENTOMOLOGIST


FOOD HABITS.-The food materials of the fire ant are largely
grass seeds, which are stored in abundance in the flat lateral
galleries in and around the mound. This hoarding habit makes
it difficult, where this ant is common, to obtain uniform stands
of grasses and other plants having small seeds. Small vegetable
seeds are removed systematically from rows in the garden if
planted near the nests. The ants so injure the bark and cam-
bium of citrus and other plants that the sap oozes out, and in
extreme cases the plants are girdled and die.
This ant will also come into kitchens and pantries to feed
upon foodstuffs. It is especially attracted to meat and milk
products, sweets, and cereals.
The fire ant viciously attacks other insects and, especially
in the early fall, feeds extensively on cutworms and grass-
hoppers. The dump heaps around the nests show fragments
of many species of insects and millipedes. This ant will eat any
animal which has recently died, but meats in advanced stages of
decomposition are not especially attractive. Fire ants have been
observed stroking aphids and feeding on the honeydew as it is
excreted, and also lapping up honeydew that has fallen on the
foliage of plants. They have not been seen, however, transport-
ing the aphids.
Plant exudates and other very moist materials are covered
with soil particles and plant debris, thus furnishing an earthen
canopy under which the ants feed. It appeared from field and
cage observations that little or no solids are eaten. In feeding
on seeds, the ants appear to extract only the oils and juices
from the germ, discarding the other parts. The seeds are fre-
quently found in a rather wet condition in the mound, tightly
packed in storage chambers.
The chief injury to quail occurs at hatching time, when the
ants enter the pipped egg and destroy the chick before it can
leave the shell. Nothing remains but the harder portions of
the skeleton. In the field it appeared that the ants often entered
the eggs before they were pipped. However, three normal quail
eggs, placed in a fire ant nest, were uninjured after 3 weeks in
the mound. Stoddard (personal communication) has seen cases
where it appeared that the ants had penetrated unpipped eggs,
and possibly they may have done so, for some quail eggs are
very soft. Damage to the nest may result in either partial or
total destruction of the eggs and young. The former is of more
importance in decreasing the quail crop because if even one








VOL. XXIV-No. 1


chick escapes, the quail will not renest, whereas if the entire
clutch of eggs is destroyed, or if the ants force the brooding
quail to desert the nest, renesting will occur. The only observa-
tion made of ants infesting nests of other birds was in the case
of a brown thrasher's nest which was situated 6 feet from a
large fire ant colony. The ants were seen climbing about over
the nestlings, but there was no apparent damage to them.
During the years 1924 to 1937 inclusive Stoddard (1931,
1932-39) and his coworkers had a total of 2,456 quail nests
under observation, of which 151, or 6 percent, were destroyed,
either all or in part, by fire ants. Such losses ranged from 4
to 16 percent annually during the period 1927 to 1937 inclusive.
No ant damage was noted during the years 1924 to 1926 in-
clusive.
The abundance of the fire ant in the shooting preserve sec-
tions of Georgia and Florida may be influenced by certain game
management practices. It is conceivable that the controlled burn-
ing programs which keep the land more open and stimulate the
growth of game-food plants may also improve the environment
for the fire ant; at least, more food is available to them on the
burned than on unburned areas.
MIGRATION.-An accurate study of migration has not been
possible because of an intricate underground system of channels
through which the ants may move. Usually migration is a com-
bination of external and subterranean movement. When the
lines of travel are external, particularly when the soil is more
plastic following a rain, the march is through termite-like
passageways formed of soil pellets.
The colony may leave the primary nest with no sign of the
direction of travel or as to where it has relocated. Some colonies
move if only slightly disturbed, whereas others remain in the
same location even when the mound is largely destroyed. Many
nests have remained in the same location for at least 4 years,
whereas others never seemed to have a permanent nest-site.
It appeared that some of the migration may be for sanitary
purposes, for all food stores are left behind. Movement of this
type was common when poisoned baits were placed in or on the
mound.
Perhaps because of the tillage of the soil by the ants, and
the accumulation of organic wastes, colony sites can be detected
by the more luxuriant vegetative growth around them. In the
early spring mounds can be be located by a mat of sprouting
grass seeds.








THE FLORIDA ENTOMOLOGIST


Certain colonies have been observed to show no external sign
of activity for as long as 8 months (May to December, 1936).
The ants in these nests did no excavating, the mound became
flattened by the weather, plants rapidly obscured the location,
and the presence of fire ants was determined only by digging
into the old mound.
LIFE HISTORY.-Six mother queens, collected in the spring,
were immediately placed in formicaries. The number of eggs
laid within the first 24-hour period after isolation ranged from
339 to 1,123, with an average of 639. Two dealated queens
collected in August laid only 15 and 25 eggs respectively within
a 20-day period. Observations on the seasonal abundance of
young in the nest also indicated a low period of reproduction
from the late summer to the early spring. Although no accurate
counts have been made, a normal colony may be composed of
several thousand major and minor workers.
Because of the cannibalistic habits of the fire ant in cages,
no detailed life-history data have been secured. Eggs kept at
air temperatures have hatched in 14 to 30 days, and at 240 C.
in 12 and 13 days. A mother queen confined in a cage reared
mature workers in 44 days.
The developmental time for queen and male prepupae and
pupae was determined from specimens collected from the ant
nests and reared in cages. The mean durations and standard
errors, in days, of the prepupal and pupal stages for each sex
were as follows: Prepupal stage, 59 queens, 5.5 0.07, and
97 males, 6.1 0.06; pupal stage, 73 queens, 18.5 0.08, and
125 males, 19.0 0.08. "Student's" t-test for significance for
the mean prepupal and pupal stages shows the differences in
developmental periods for each sex to be significant.
A count of 2,632 alate pupae and imagoes indicated a sex
ratio of queens to males of 5:6, but rarely were the sexes evenly
distributed within a single colony. Sexual larvae were first
recognized in the colonies April 19, 1936, April 27,2 1937, and
April 2, 1938; alate forms were first seen May 7, 1936, May
18, 1937, and May 10, 1938; the first flights were seen June
9, 1936, June 2, 1937, and May 28, 1938. The last immature
sexual forms were seen in the colonies (in 1936-38) during the
first half of the month of October, when 20 percent of the
colonies contained immature individuals. Up to the last of
"At Immokalee, Fla., male and queen prepupae were present February
9, 1937.








VOL. XXIV-No. 1


December alate forms were found in about 25 percent of the
colonies, and all were gone by the middle of January.
The flights of the winged forms occurred between 5:00 and
6:30 p. m. on days following rains. No normal flights were
noted during periods of drought, but heavy sprinkling of the
ground stimulated flights.
While the alate forms were issuing from the nest and until
the flight stopped, the workers appeared excited and swarmed
about over the mounds. Frequently the queen started her flight
with workers clinging to her. The queens usually climbed high
on vegetation to start the flight, whereas the males tended to
fly more directly from the mound. Flights occurred from the
same nest over a period of at least several weeks. The queens
and males exhibited no sexual excitement either at the colony
or in the cages.
To determine whether the alate queens would lay fertile eggs,
a series of 670 winged queens were collected as they flew from
the nests and were confined in cages both with and without
males. Of these, 503 did not oviposit, and 167 laid from 1 to
273 eggs per queen. Forty of the queens shed their wings be-
fore laying eggs, and eight that shed their wings did not oviposit.
The first eggs appeared 7 to 15 days after the queens were col-
lected. They were cared for by the queens, but no embryos
developed.
No more than one functional queen has ever been located
in a colony. However, in each of 12 mounds under observation
the number of workers dwindled for about 3 months after the
mother queen was removed, and then new broods suddenly ap-
peared in 7, while all activity ceased in 5. The seven nests
continued active for over 3 years, and at least for the first 2
years no sexual forms, either alate or dealate, could be located.
At the end of 2 years slight activity had been resumed in 4 of
the 5 inactive colonies. It is not known whether these were
new ants or were some of the original colony.
As a further check on the reproduction of young after the
queen had been removed, 13 colonies of workers were collected
with an aspirator and moved to new locations without young
or a queen. Two of these groups persisted for about 2 months
and finally disappeared. The other 11 never established a nest,
but dispersed and disappeared.
The observation that colonies continued to reproduce after
the mother queen was removed is important in the control of
ants. It has been generally assumed that when the queen is








THE FLORIDA ENTOMOLOGIST


destroyed the colony will not survive. Unless each fire ant colony
possesses more than one queen-and there is no proof that they
do-the elimination of the queen does not necessarily mean the
destruction of the colony.
FIGHTING INSTINCTS.-Unlike many species of ants, fire ants
swarm rapidly out of the colony to attack an intruder. Merely
the blowing of the breath on the mound, or the stamping of the
foot near the mound, calls forth hordes of fighters. Once they
are on the intruder they fasten firmly with their sharp mandibles
and double up to insert their sting near the point where they
are holding with their jaws; both their bite and their sting are
painful.
If a colony moves within the territory of another there is
a fierce battle. The lion ants, Dorymyrmex pyramicus var. flavus
MacCook and Dorymyrmex pyramicus var. niger Pergande, con-
tinually harass the colonies, particularly if the nest has been
weakened. When the lion ants are attacking, the fire ants will
be seen clinging to the ground with the posterior end of the
abdomen lifted high, pointed at the foe, and waving nervously
around. Occasionally a drop of liquid can be seen on the tip
of the abdomen. The lion ant strives to grasp his adversary
without coming in contact with the posterior end of the fire ant.
If the tip of the abdomen is touched-in fact, it appears that
the actual contact is not necessary-the attacker will suddenly
dash away and rub itself hurriedly on the ground as though
attempting to rub off the irritating substance. After a short
period of cleaning it is ready to attack again cautiously. Only
rarely were fire ants observed to be disabled by the lion ants.
The only ant that was observed to subdue the fire ant was Cam-
ponotus abdominalis subsp. floridanus (Buckley). This ant
would approach fire ants and rapidly cut them up with its
mandibles. If a fire ant succeeded in grasping its large relative
it was pulled off and killed.
ENEMIES.-Two small colonies of fire ants were observed to
be destroyed by a large colony of the legionary ant, Eciton (Nei-
vamyrmex) nigrescens (Cresson). During February and March
the migrating sparrows scratch nearly every mound flat in quest
of the stored seeds. Cotton rats also feed on these seed supplies
during January and February. Stoddard (personal communica-
tion) has observed brooding quail feeding on the ants as they
came within reach, and from the numbers of these insects in
the crops of such birds concluded that the quail might protect
the hatching chicks if the ants were not too numerous.









VOL. XXIV-No. 1


MYRMECOPHILES.-Particularly where the fire, ant is com-
mon, there are small scarabaeid beetles, Euparia castanea Serv.,
in the ant nests. The ants carefully tend these beetles and in
the cages continually clean them at the junction of the elytra
and the pronotum. In several colonies the myrmecophilic
cricket, Myrmecophila sp., was found. The thief ant, Solenopsis
molest (Say), builds its tunnels between those of the fire ant.
The mealybug Pseudococcus sp. occurred frequently on the roots
of broom-sedge in the fire ant nests. A tarsonemid mite of the
family Disparipedidae was frequently seen riding about on the
ants. While on the ants, the mites stand rather erect, bobbing
up and down and tapping the ant with the first pair of legs.
They have been seen to feed on liquids on the mouthparts of
ants and occasionally they feed on the excreta at the anal open-
ing of the ant. The ants frequently attempt to dislodge the
mites when they first attack, but usually the ants pay no atten-
tion to them. Two staphalinid beetles lived in the ant mounds;
one belonging to the subfamily Tachyporinae was present when
the colony was occupied, and the other, Paederus littoreus Aust.,
was usually seen only when the colony was deserted.
SUMMARY.-The biology of the fire ant, Solenopsis geminata
(F.), has been studied in northern Florida and southern Georgia.
The mound of this ant is a high, irregularly shaped pile of earth
with lateral tunnels that radiate from 6 inches to more than
100 feet from the mound, and with vertical tunnels that extend
6 or more feet deep.
The fire ants are omnivorous in habit, but they feed mainly
on small seeds which are stored abundantly in the nests. They
seem to take only the juices from their food materials and dis-
card the solid portions.
An accurate study of migration has not been possible be-
cause the ants move readily through underground passages.
Some colonies never seem to have a permanent nest-site while
others have been observed to remain in the same location for
at least 4 years. Colonies have been observed to remain inactive
for as long as 8 months.
Captive mother queens laid as many as 1,123 eggs in a
24-hour period. The eggs hatched in 14 to 30 days, and workers
were reared to the adult stage in 44 days at summer tempera-
tures. Alate queens and males had a prepupal stage, respec-
tively, of 5.5 and 6.1 days, and a pupal stage respectively of
18.5 and 19.0 days. A sex ratio of queens to males was 5:6 for









THE FLORIDA ENTOMOLOGIST


a sample of 2,632 individuals. Sexual larvae first appeared in
the mounds April 2 to 19; alate forms, May 7 to 18; and first
flights, May 28 to June 9. The flights occur between 5:00 and
6:30 p. m. on days following rains. Alate forms were present
in 25 percent of the colonies up to the last of December. Some
winged queens, captured as they flew from the nests, laid eggs,
but these were not fertile. Seven of 12 colonies, from which
mother queens were removed, continued to produce young for
over 3 years.
When disturbed, the fire ants swarm from their colony to
attack an intruder. Both their bite and sting are painful.
The legionary ant, Eciton (Neivamyrmex) nigrescens (Cres-
son), has been observed to destroy two fire ant colonies. Cotton
rats and migrating sparrows dig into the mound in the spring
and rob the seed stores of the fire ant.
The following myrmecophiles were collected from fire ant
colonies: a scarabaeid beetle, Euparia castanea Serv.; a cricket,
Myrmecophila sp.; the thief ant, Solenopsis molesta (Say);
mealybugs, Pseudococcus sp.; a tarsonemid mite belonging to
the family Disparipedidae; and two staphilinid beetles, Paederus
littoreus Aust., and a species belonging to the subfamily Tachy-
porinae.
LITERATURE CITED
CLARK, S. W. 1931. The control of fire ants in the lower Rio Grande
Valley. Tex. Agr. Expt. Sta. Bul. 435, 12 pp., illus.
EAGLESON, CRAIG. 1940. Fire ants causing damage to telephone equip-
ment. Jour. Econ. Ent. 33: 700, illus.
EMLEN, JOHN T., JR. 1938. Fire ants attacking California quail chicks.
The Condor 40: 85-86.
GORSUCH, DAVID M. 1934. Life history of the Gambel quail in Arizona.
Univ. Ariz. Biol. Sci. Bul. 2, 89 pp., illus.
MALLIS, ARNOLD. 1938. The California fire ant and its control. Pan-
Pacific Ent. 14: 87-91.
SMITH, M. R. 1936. Consideration of the fire ant Solenopsis xyloni as
an important southern pest. Jour. Econ. Ent. 29: 120-122.
STODDARD, H. L. 1931. The bobwhite quail, its habits, preservation and
increase. 559 pp., illus. New York. (See pp. 193-194.)
.1932-1939. First to Seventh Annual Reports of the Co-
operative Quail Study Association.
TRAVIS, BERNARD V. 1938. Fire ant problem in the Southeast with special
reference to quail. Trans. 3d N. Amer. Wildlife Conference, pp. 705-708.
.1938a. The fire ant (Solenopsis spp.) as a pest of quail.
Jour. Econ. Ent. 31: 649-652.









VOL. XXIV-No. 1


ENTOMOLOGICAL PROBLEMS IN THE EVERGLADES
J. W. WILSON
Everglades Experiment Station
In this discussion of the Entomological problems of the Ever-
glades it may be well to first consider briefly the geology of the
area. Most of you are at least casually acquainted with the area
around Lake Okeechobee, but probably many of you know of
this part of the state only from hearsay.
The Floridian plateau,' as described by geologists, has been
in existence since very ancient time. It was probably dry land
during the Triassic and Jurassic periods and the Lower Cre-
taceous epoch, but it was covered by the sea during part of the
Upper Cretaceous time. During the Cenozoic era its shore under-
went many shifting, but it was never very deep under water nor
has it been lifted very high above sea level. Since Florida is
far from the Piedmont Plateau, the origin of all sand and gravel,
the original sedimentary deposits contained more limestone than
sand or clay.
The mica schists, quartzites and other rocks that form the
foundation of the Floridian plateau are about 4100 feet below
the surface and are only slightly known.
One class of lakes in Florida are those that fill original de-
pressions in the floor of the sea. Lake Okeechobee, 35 miles
across, and next to Lake Michigan, the largest body of fresh
water wholly within the United States, is the most conspicuous
example of this class. The Everglades form a level, grassy plain
that slopes gently southward from an altitude of about 18 feet
above sea level near Lake Okeechobee, and merges into the
mangrove-covered keys in Florida Bay. This plain is underlain
with Pliocene shell marl and limestone, which is generally cov-
ered by six to eight feet of peaty muck. Before their artificial
drainage the Everglades was usually flooded, but now so much
of the water is carried off by canals that the higher parts stand
above normal water level.
For convenience in this paper I have arbitrarily divided the
subject into two parts, problems of management and problems
of entomology. All of us are quick to admit that climate, soil,
plant diseases, etc., interact and react upon the insect popula-
tions. As a result there should be the fullest cooperation be-

1Cook, C. Wythe, and Stuart Mossom, Geology of Florida, Twentieth
Ann. Rept. Fla. State Geology Survey, pp. 37-43, 1929.









THE FLORIDA ENTOMOLOGIST


tween the entomologist, soil chemist, horticulturist and plant
pathologist. It is readily admitted that with cooperation be-
tween the various branches of agricultural research experiments
can be designed that would give more reliable information on
all the factors involved. This information could be obtained
more quickly and cheaply, and would be more accurate than
results so far obtained. It is ridiculous for the entomologist
to ignore the problems of soil management, plant pathology or
horticulture. He could not grow his crops for experimentation.
It is then even more ridiculous to publish entomological findings
when the same crops could be treated more effectively in a joint
publication giving the results of the work of the several men
concerned, where the experiments have been designed and car-
ried out in a spirit of true cooperation. The practical farmer
is forced to consider soil management, plant pathology, horti-
culture and entomology all at the same time. It is, therefore,
somewhat confusing for him to have to read publications which
discuss his problems from only one angle. We sometimes com-
plain that the farmer does not readily put into practice our
recommendations. I feel that this lack of cooperation between
the various research fields may be largely to blame. What is
the farmer to do when he gathers the horticultural, plant pathol-
ogical, and entomological publications and finds glaring con-
tradictions or recommendations impossible to follow because of
conflicts with other necessary farm operations? We are ex-
pected to be leaders and if we are to lead we must first learn
to cooperate among ourselves.
An example showing the benefits of interdepartmental co-
operation can well be personally illustrated as follows: After
testing several insecticides for the control of the corn budworm,
Laphygma frugiperda S. and A., and finding effective sprays
too costly for commercial corn production, the agronomist and
myself designed an experiment to compare various spray ma-
terials with different spacings of corn. The results showed that
far more effective control of the budworm was obtained by
simply making closer plantings than by the use of any of the
insecticides tested. This control was probably due to the same
number of insects attacking a greater number of plants with
proportionately less damage. This example illustrates the bene-
fits resulting from cooperation and shows the possible effective-
ness of experiments designed to cover all phases of a problem.









VOL. XXIV-No. 1


Other problems of management which the entomologist
should consider are those of climate, drainage and irrigation.
Time does not permit a full discussion of these subjects. An-
other important problem of entomological research is the finan-
cial problem. I expect that the research man never existed who
was completely satisfied with his research conditions. His
budget is too limited (which is too frequently the case), his
surroundings are not satisfactory, or a number of other minor
dissatisfactions may be present. However, the problems of a
limited budget are the most common source of irritation. We
love to dream of what we would do if our budget were unlimited,
but fortunately this is not a dream world. We are forced to do
the best we can with what we have and that best can be excel-
lent if we really exert ourselves to the utmost.
Now let us take up the special entomological problems of the
Everglades. I have listed first the effect of climate on insect
populations and insect research. In the Everglades the bean
leaf hopper, Empoasca fabae Harr., is present in destructive
numbers usually only in the spring, while in the central part
of the state it is present only in the fall. I have done some
speculation as to why this is true; but to the present time spec-
ulation is as far as the problem has progressed.
Our crops are grown from September to June because of
the climate. As a result aphids on pepper, tomatoes and English
peas are particularly difficult to control. These insects are most
abundant during December and January. These are periods
when comparatively low temperatures, and high winds prevail.
The insecticides we now have are most effective during periods
of calm weather when the temperatures are 800 F. or above.
Another problem resulting from climatic effect is the periodic
outbreak of such insects as the onion thrips, Frankliniella tabaci
Lindm., on beans. During the spring of 1937 tobacco thrips
became so abundant that it was economically impossible to con-
trol this insect.
In the Everglades such large areas are planted to single crops
that most growers have turned to the practice of applying in-
secticides and fungicides by airplane. It is not necessary to
discuss these problems as they have already been ably presented
to this society by Dr. Ralph Miller in his presidential address
in December, 1937.
Other special problems which I shall take time to only men-
tion are the sugarcane borer, wireworms, mole crickets, cut-









THE FLORIDA ENTOMOLOGIST


worms and army worms. Heretofore, the principal means of
control for the sugarcane borer, Diatraea saccharalis Fab., has
been the introduction of parasites. These are no doubt beneficial
but the borer population is steadily increasing. One peculiar
phenomena that has not been explained is the fact that the
Eastern Division of the U. S. Sugar Corporation has approxi-
mately five times the borer infestation of the Western Division.
Dusting with cryolite is being investigated and shows much
promise. Wireworms, Melanotus communis (Gyll.) and Aiolus
dorsalis Say, are causing increasing damage to both cane and
truck crops. It has been shown that these insects can be con-
trolled with several soil fumigants, but these materials are not
economically feasible. The only practical solution of the prob-
lem appears to be flooding during the peak of adult emergence
or clean cultivation. Mole crickets are now causing great losses
in the Plant City and other areas. The species present on the
Experiment Station land, recently identified as Grylotalpa hexa-
dactyla, is increasing in abundance. Cutworms and armyworms
of several species occasionally cause severe damage. Their
periodic abundance is probably due to climatic factors which
have not been studied in the Everglades. The bean leaf roller,
Goniuras proteus L., is frequently a serious menace to the pro-
duction of snap beans during the fall.
There are a number of other problems which need attention.
Now we have gotten back to the problems of finance and it is
time to close. However, I would like to emphasize again the
need for more money to work with and above all the need for
more cooperation in the future between the various workers.


FLORIDA ENTOMOLOGICAL CONFERENCE
The next Florida Entomological Conference sponsored by the
Newell Entomological Society will be held in Gainesville, March
27, 28, 1941. The Conference will feature the Silver Anniversary
of the Plant Quarantine Service in the State of Florida as con-
ducted by the State Plant Board. Dr. Lee A. Strong, Chief of
the Bureau of Entomology and Plant Quarantine will be honor
guest. Quarantine officials from all parts of the United States,
Canada, and South America are invited to attend.

Any member of the Florida Entomological Society may ob-
tain the Constitution and By-Laws, adopted at the 1939 annual
meeting, by requesting a copy from the Secretary or the Editor
of the FLORIDA ENTOMOLOGIST.




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