HOME GARDENER'S LAWN
INSECT CONTROL GUIDE
JAMES E. BROGDON and S. H. KERR
ida Agricultural Extension Service
itute of Food and Agricultural Sciences
versity of Florida, Gainesville
HOME GARDENER'S LAWN INSECT
JAMES E. BROGDON
S. H. KERR
Several insects and related pests are common in lawns in
Florida. The chinch bug (Figs. 1 and 2), leafhoppers and scales
suck plant juices. Some, as mole-crickets and billbugs, live in
the soil and damage the plant roots. Others, including sod web-
worms (Figs. 7 and 8) and armyworms, eat the grass leaves.
To these groups can be added other insects and related pests,
such as fleas, earwigs, millipedes, chiggers and snails, that do
not damage the lawn but may become nuisances because of their
biting people or crawling into houses, garages, swimming pools,
Fig. 1.-Chinch bugs (much enlarged). Note long-winged adults (right),
short-winged adults (top), and wingless nymphs (left).
LOOK FOR INSECTS
To prevent extensive damage by insect pests, homeowners
should make frequent thorough inspections of their lawns, espe-
cially during spring and summer, so that insect infestations can
be found early and treatments applied promptly.
Insects are only one of many causes of yellowish or brownish
areas in grass. Diseases, nematodes, dry weather and nutri-
tional disorders are frequently responsible for such injury.
It is important that homeowners be sure of the cause so the
proper treatment can be used promptly to correct the trouble
without the needless waste of pesticides and without further
damage to the grass.
Fig. 2.-Chinch bugs, adults and nymphs. Note adults are not as long as
the blade of grass is wide.
The chinch bug is the most important pest of lawns in Florida.
It is seriously damaging only to St. Augustinegrass. This in-
sect sucks the plant juices through its needle-like beak and also
apparently causes other internal injury in the grass, resulting
in yellowish to brownish patches in lawns. These injured areas
frequently are first noticed along edges of lawns.
Usually when chinch bugs are present in sufficient numbers
to cause yellow or brown areas in lawns, they can be found by
pushing aside the grass runners in the yellowed areas and look-
ing down at the soil surface. The small black or red bugs with
white markings on their backs will be seen scurrying along on
and in the loose duff on the soil surface. In extremely heavy
infestations some of the chinch bugs can be seen crawling over
grass blades, sidewalks and outside walls of houses.
Fig. 3.-Metal can for finding chinch bugs. Both ends have been removed.
If no chinch bugs are seen by this method, their presence
or absence can be confirmed by using a metal can such as a
3-pound shortening can, a large coffee can or a gallon can with
both ends cut out (Fig. 3). Place one end of the can on the
grass in an area where the grass is yellowed and declining. Cut
the grass runners around the bottom edge of the can with a
knife. Twist and push the bottom end of the can an inch or
two into the soil (Fig. 4). Fill the can with water (Fig. 5)
and if chinch bugs are present, they will float to the surface
within 5 minutes (Fig. 6). It may be necessary to add more
water to keep the water level above the grass during this 5-
minute period. If no chinch bugs are found in the first area
checked, examine at least 3 or 4 places in the suspected areas.
When it is definitely established that chinch bugs are the
problem, start control measures immediately.
1. Have the turf moist at the time it is sprayed. If it has
become dry, irrigate the lawn by running the sprinklers about
an hour. This aids in the spread and penetration of the spray
into thick turf mats. (It is not necessary to have the turf moist
before granular insecticides are applied.)
2. Treat the entire lawn thoroughly, giving particular at-
tention to areas obviously heavily infested. Make spot treat-
ments only if you can watch the lawn from day to day.
Fig. 4.-Push can into yellowed grass.
3. Use effective insecticides. Recommended materials include
V-C 13, ethion, Trithion, diazinon, Aspon, Zytron, and Baygon.
4. Apply the insecticide properly. When using sprays it
is important to apply the insecticide in a large amount of water
in order to soak the thick mats of St. Augustinegrass.
Jar attachments to garden hoses are excellent tools for
home gardeners to use to apply sprays. Use the type which
requires 15 to 20 gallons of water passing through the hose
to empty the quart size jar. Put the amount of insecticide in
Fig. 5.-Fill can with water to float chinch bugs.
Fig. 6.-Watch for chinch bugs to float to the surface of the water.
FLORIDA LAWN PEST CONTROL CHART
CONTROL (see text for important points on applying insecticide)
The chinch bug
common in Flor-
ida lawns is
Adults about % inch long, black
with white patches on wings
which are folded over back.
Young (nymphs) range from
1/20 inch long to nearly adult
size. The smallest chinch bugs
are reddish with a white band
across the back, but become
black in color as they near adult
Sometimes adults hibernate in
winter in Northern Florida,
but all stages present year
around in most of the state.
Eggs laid in leaf sheaths or
pushed into soft soil and other
protected places. In summer
hatch 1-1 weeks; young de-
velop to adults in 4-5 weeks,
adults may live many weeks.
Of the lawn grasses, only St.
Augustinegrass is seriously
injured. Bugs insert a slen-
der, piercing beak into grass
and suck plant juices. Typ-
ical injury shows as a patch
with brown, dead center and
Per 500 Sq. Ft.
(for qt. size
Aspon 6E (6 lbs. per gallon EC*) 2-21 fluid oz.
Baygon 1.5E (1.5 lbs. per gallon EC) 8 fluid oz.
Diazinon 2E (2 lbs per gallon EC) 3-6 fluid oz.
Dursban 2E (2 lbs per gallon EC) 1 fluid oz.
Ethion 2E (2 lbs. per gallon EC) 5%-8 fluid oz.
Trithion 2E (2 Ibs per gallon EC) 5-8 fluid oz.
V-C 13 (8E) (8 lbs. per gallon EC) 3-6 fluid oz.
Granulated forms of above insecticides: apply
spreader as directed on the label.
18-24 fluid oz.
80 fluid oz.
32-64 fluid oz.
7%-11 fluid oz.
54-74 fluid oz.
54-74 fluid oz.
32-64 fluid oz.
with a fertilize:
Caterpillar grows to % inch in Adults lay eggs among grass. The caterpillars are the only Per 1,000 Sq. Ft. Per 10,000
Sod Webworms length; greenish. Adults are Eggs hatch in about 1 week. damaging stage. They de- (for qt. size hose Sq. Ft.
dingy brown moths with wing- Larvae feed on grass blades your the foliage, feeding only sprayer) (Per 100
In Florida-and spread about % inch. and grow large enough to at night. Damage usually Toxaphene emulsifiable con- Gallons)
particularly in cause noticeable injury within seen in patches. Grass blades centrate (6 lbs. per gal.).... 1/ cup 1 % pints
the summer 2 weeks. Much damage next notched on sides and chewed 40% Toxaphene wettable
time-the one 1-1% weeks till pupation. back raggedly. Grass may powder .................. ......... 11 cups 3 pounds
found princi- Adult. appears about 1 week die if foliage stripped off in 50% Sevin wettable powder .... 1% cups 2% pounds
pally is later. They complete their hot, dry weather. 25% DDT emulsifiable
Pachyzancla life cycle in 5-6 weeks and concentrate ............................ 1 cup 2% quarts
phaeopteralis have several generations a .50% DDT wettable powder ...... 1/ cups 2 pounds
DUSTS: Apply 10% toxaphene dust to the grass at the rate of
1 lb. per 1,000 square feet, or apply 5% DDT dust or 5% Sevin
dust at the rate of 2-2%1 lbs. per 1,000 square feet.
Armyworms Caterpillar grows to 1% inches Moth lays eggs on grass and Caterpillars chew the grass
The one found long. Greenish when small; on almost any object near blades. Turf appears rag-
principally is dark brown when full grown. lawns. Development is much ged, and foliage may be
the fall army- Has a light mid-stripe along like sod webworm. Army- stripped off. Feed during Control is the same as for sod webworms.
worm, back; darker bands on each side worms pupate in the soil, how- the day and damage often
Laphygma of mid-stripe. Midstripe ends in ever. not in as definite patches as
frugiperda inverted V on head. that of sod webworms.
(J. E. Smith)
Mole-Crickets Odd-looking crickets growing to In spring, adult places eggs Make burrows in soil, loosen Per 500 Per 5,000
The principal 1% inches long. Have velvety in underground cells. Eggs soil, disturb and cut off roots. Sq. Ft. Sq. Ft.
ones found in appearance from covering of hatch in 1-2 weeks in warm Found more commonly in 1.5-2% chlordane bait ............. 1-2 pounds 10-20 pounds
Florida lawns fine, brown hairs. Front legs weather. Become adults by soft, newly planted areas, 23% aldrin or heptachlor
are the south- flattened and adapted for bur- fall. but .can be serious in estab- emulsifiable concentrate .... 6 tablespoons 1 quart
ern mole-crick- rowing. lished turf as well. 25% heptachlor or aldrin
et, Scapteriscus wettable powder ................ 1 cup (1/ pound) 2 pounds
acletus R. & H., Chlordane emulsifiable con-
and the Puerto centrate (8 lbs. per gal.).... 1/ cup 1/4 pints
Rican mole- 40-50% chlordane
cricket, S. wettable powder ............ 1 cup (/4 pound) 2 pounds
vicinus Scudd. 50'/ Kepone wettable powder.... % cup 1 pounds
White Grubs Larvae are fat grubs which lie Adults lay eggs in the soil. Grubs damage grass by de-
These include in C-shaped position. Whitish Grubs which hatch out live in vouring r o o t s. Yellowish
the May or June in color with dark areas at rear. the soil and feed on roots. areas develop in turf, and
beetles, Phyl- Brownish head. Adults are Different species take varying grass can be killed. In se-
lophaga spp.; beetles. times to go through life cycle vere cases, roots pruned off Chlordane, aldrin or heptachlor sprays as for mole-crickets
Green June -1 to 4 years. Adults do not to extent that the turf mat
beetle, Cotinis feed on grass. can be rolled back like a car-
nitida (L) ; and pet.
EC is abbreviation for emulsifiable concentrate.
Liquid Measures: 3 teaspoons = 1 tablespoon 2 tablespoons = 1 fluid ounce 8 fluid ounces = 1 cup 2 cups = 1 pint 2 pints = 1 quart 4 quarts = 1 gallon.
the jar for 500 square feet (see chart). Fill the jar the rest of
the way with water. Spray out the contents over 500 square
feet of lawn (10 by 50 feet or 20 by 25 feet). To insure even
coverage, spray back and forth across the measured area; then
turn at right angles and spray back and forth across the same
A sprinkling can is satisfactory for use on small areas. In
a 2-gallon sprinkling can put 2 to 4 teaspoons of 25% diazinon
or 75% V-C 13, or 4 teaspoons of Trithion 2E or ethion 2E,
or 1/ tablespoon of Aspon 6E, or 1 tablespoon of Zytron 3E, or
2 tablespoons of Baygon 1.5E. Stir well and apply the 2 gallons
carefully over 50 square feet of lawn.
Some of these materials are on the market in dry, granu-
lated form for direct application with fertilizer-spreader ma-
chines. These formulations are just as effective as sprays when
applied as directed. Follow the directions on the label. It is
not necessary to have the turf moist at time of spreading the
granulated insecticides. They should be washed down into the
turf mat after application.
The lower dosages of insecticides given in the control chart
have performed well in Experiment Station tests. Since most
home gardeners do not apply insecticides as carefully as in
experimental work, and since the chinch bug problem is es-
pecially severe in some of the more southern parts of Florida,
the higher dosages may be needed. The amount of insecticide
per unit area is given in the control chart.
Several lawn spray mixtures combining more than one pest-
icide effective against chinch bugs and other common lawn
pests are on the market. When using these, follow directions
on the labels.
5. Continue to watch for chinch bugs, since one insecti-
cidal treatment rarely prevents damage for a whole season.
Two or 3 applications per year are needed in most of Florida,
and even more may be required under extreme conditions, par-
ticularly in South Florida.
While a common approach to chinch bug control is to be
vigilant in watching for their appearance and to treat promptly
when they do appear, some people prefer to use a preventive
program. Such a program would call for the first treatment
to be applied in March in southern Florida and for subsequent
treatments at about 6-week intervals. In average years, the
initial treatment can be made later as one moves farther north-
ward, so that in the northern third of the state late May usually
would be soon enough to begin.
SOD WEBWORMS AND ARMYWORMS
Several kinds of caterpillars, which are the immature or
larval stage of moths, may cause damage to various lawn grasses.
The principal ones are the tropical sod webworm (Figs. 7 and
8) and the fall armyworm.
Sod webworms differ from armyworms in size and feeding
habits. The webworms feed primarily at night and remain in
a curled position on or near the soil surface during the day
(Fig. 7). This habit makes them difficult to find. The newly
hatched caterpillars cause very little visible damage to grass.
It is not until they are almost full grown "worms" nearly :,
inch long that their feeding becomes very noticeable, and then
it appears to show up almost overnight. This, along with their
night feeding habit, explains how extensive damage may occur
before it is noticed.
Injured grass has notches chewed into the sides of the blades
Fig. .-Grass parted to show sod webworm in its daytime resting position.
Fig 7.-Grass parted to show sod webworm in its daytime resting position.
and the blades are eaten back unevenly. The foliage may be
almost completely stripped off in patches, and these close-cropped
areas have a yellowish to brownish appearance.
Fig. 8.-Tropical sod webworm. Adult moth, left center; webworm cat-
erpillar, right center; pupae or resting stage, upper center. Note chewed
grass and pellets of excrement.
A good way to search fo or sod webworms is to part the grass
and look for the small green "worm" curled up near the soil
(Fig. 7) and for small green pellets of frass or excrement (Fig.
8). A flashlight used at night will reveal the caterpillars work-
ing in the grass foliage.
Armyworms grow to about 11/2 inches in length, or about
twice the length of the full grown sod webworm. They feed
during the day and do not rest in a curled position.
Toxaphene, Sevin, or DDT is excellent for lawn caterpillar
control. However, a number of other materials, including BHC,
diazinon and dieldrin, give satisfactory control. The lawn
sprays commonly sold by garden supply stores usually contain
a mixture of 2 or more insecticides for the purpose of controll-
ing these chewing caterpillars as well as chinch bugs and cer-
tain other pests. Dust and granules can be used effectively.
Fig. 9.-The most widespread and destructive mole-crickets. Left,
Puerto Rican (Scapteriscus vicinus Scudd.); right, Southern (S. acletus
R. & H.). (From Agricultural Experiment Station Circular S-15.)
MOLE-CRICKETS, BILLBUGS, WHITE GRUBS
The damaging stages of this group of insects are soil dwell-
ers that feed on roots. Mole-crickets (Fig. 9) make burrows
like tiny mole tunnels (Fig. 10). They are most destructive in
newly seeded or sprigged lawns where they cut off the grass
roots and loosen the soil so that excessive drying occurs.
The hunting billbug sometimes causes severe injury to grass
in Florida, especially to Zoysiagrass. As the name suggests,
the adult beetle has a bill or snout. The larva or grub, which
is legless and grows to about 3/8 inch in length, is white in
color, with a yellowish brown head. This stage causes most
of the damage to grass by feeding on the roots and causing dead
areas in lawns and other turf. Baygon, at the amounts recom-
mended for chinch bugs, has been one of the better materials
for control of billbugs.
Several species of white grubs damage grass. These pests
are the larval stage of beetles such as May or June beetles.
Unlike billbug larvae, white grubs have 3 pairs of small legs
near the head end. They are generally distributed in Florida,
but are not considered to be major pests of lawns.
.. -- "
. : . ~ 44
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Fig. 10.-Mole-cricket "runs" on newly graded yard. (From Circular S-42.)
The method of control is similar for all of these soil dwell-
ing pests. Again, the hose attachment sprayer discussed under
chinch bugs can be employed effectively, using the amounts
of insecticides given in the control chart. It is important to
use large amounts of water to get the insecticide down to where
the insects are feeding. If large amounts of water cannot be
applied with the sprays, irrigate after spraying. The baits
given in the chart are effective in control of mole-crickets.
Fig. 11. -
Earwigs are brownish insects which grow to
about an inch in length and have forceps-like
appendages at the rear (Fig. 11). Although they
breed in lawns, they are not harmful toothe grass.
They may become nuisances by crawling into
r nom Circular
S-96. r These insects are difficult to control and re-
peat applications at 2-week intervals may be
needed. Sevin at the rate for sod webworms and diazinon or
Baygon at the rate for chinch bugs (See Chart) are recom-
mended. BHC and lindane are also suggested. The amount for
1,000 square feet of lawn is 1/4 pound (1 cup) of 12 percent
gamma isomer BHC wettable powder, or 5 tablespoonfuls of
15-20 percent lindane emulsion concentrate. Apply this amount
of insecticide in 10 to 15 gallons of water when using a power
With a hose attachment sprayer or other smaller equip-
ment, apply 2 tablespoonfuls of the BHC wettable powder or 11/
teaspoonfuls of the lindane emulsion concentrate per 100 square
feet of lawn. Application of one of the above insecticides as
granules or as a dust in a band about 10 feet wide around a
house should be helpful. Repeat as needed.
Fig. 12. Millipede
(from Circular S-96)
Millipedes (Fig. 12) or "thousand-
legged worms" are not a threat to grass.
They feed primarily on decaying vege-
tation, but may feed on the tender
parts of plants. They annoy by crawl-
ing into houses, swimming pools, etc.
Control of millipedes is very diffi-
cult. Repeated applications of pesti-
cides at 2-week intervals is usually
needed to substantially reduce the pop-
ulation. Diazinon or Baygon (as for
chinch bugs), Sevin (as for sod web-
worms) or BHC or lindane (as for
earwigs) are suggested. Give special
emphasis to spraying the foundations
. of buildings, porches, patios, etc. A
S dust barrier (as for earwigs) around
the house should be helpful.
Insecticides are poisons and should be handled as such.
Read completely the manufacturer's label on the container be-
fore opening and observe all precautions. Wear rubber gloves
when handling and applying insecticides. Do not breathe mists
or fumes or spill sprays on the skin. Wash exposed parts of the
body after using insecticides. Store pesticides in original labeled
containers out of reach of children. Dispose of empty containers
promptly and safely.
A Revision of Circular 181
Second Revision March 1961
Third Revision April 1964
Fourth Revision June 1965
Fifth Revision April 1967
COOPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS
(Acts of May 8 and June 30, 1914)
Agricultural Extension Service, University of Florida,
and United States Department of Agriculture, Cooperating
M. O. Watkins, Director
BEO UIG N