Circular 181 May 1958
COOPERATIVE EXTENSION WORK
AGRICULTURE AND HOME ECONOMICS
(Acts of May 8 and June 30, 1914)
Agricultural Extension Service, University of Florida,
Florida State University and
United States Department of Agriculture, Cooperating
M. O. Watkins, Director
LAWN PEST CONTROL GUIDE
JAMES E. BROGDON S. H. KERR
Agricultural Extension Service Agricultural Experiment Station
Several insects and related pests are common in lawns
in Florida. The chinch bug, leafhoppers and scales suck
juices. Some, as white grubs and billbugs, live in the
soil and attack the plant roots. Others, including sod
webworms 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.
LOOK FOR INSECTS
To prevent extensive damage to lawns by insect pests,
ome owners should make frequent, thorough inspections,
specially during spring and summer, so that early insect
infestations can be found and treatments applied promptly.
Insects are only one of many causes of yellowish or
rownish areas in grass. Diseases, nematodes, dry
weather and nutritional disorders are frequently respons-
ble for such injury. It is important that homeowners
e sure of the cause so the condition can be promptly
Timely spraying will control most of the insects
corrected without the needless waste of pesticides and
without further damage to the grass.
The chinch bug is probably the most important pest
of lawns in Florida. It is seriously damaging only to
St. Augustinegrass. This insect sucks the plant juices
and possibly injects toxic substances, causing yellowish
to brownish patches in lawns. These injured areas are
frequently found along concrete walks and drives.
Usually when chinch bugs are present in sufficient
numbers to cause yellow or brown areas in lawns, they
can be found by parting the grass in the yellowed areas
and making close observations. If this is not successful,
take a large metal can with both ends cut out. Push one
end about two or three inches into the ground in the
yellowed portion of the grass or at the margin of the
damaged area. Fill with water and if any chinch bugs
are present, they will float to the surface within 5 minutes.
If it is difficult to push the can through the St. Augustine-
grass runners, a knife may be used to cut a circle in the
grass the size of the can.
When it is definitely established that chinch bugs are
the problem, start control measures immediately.
1. Just before spraying, irrigate the lawn by running
the sprinklers about an hour.
2. Treat the entire lawn evenly and thoroughly. Make
spot treatments only if you can watch the lawn from
day to day.
3. Insecticides to use:
DDT has been the standby in chinch bug control for
several years. Although it still performs well in Nort
Florida, it is becoming increasingly difficult to obtain con
trol with DDT in some areas of the state.
Diazinon is a newer insecticide which home owners ca
use. It has given excellent initial control, but a second
application 1% to 2 weeks after the first should be mad
for best results.
V-C 13, first marketed as a nematocide, has proved t
be a good chinch bug killer. It is comparatively expen
sive but only one application is needed, since it gives goo
long-term residual control.
Parathion-See discussion on this material.
Several lawn spray mixtures which are effective against
chinch bugs and other common lawn pests are on the mar
ket. When using these follow directions on the labels.
The lower dosages of insecticides given in the contr
chart have performed well in recent tests. Since mo
home owners do not apply insecticides as carefully as i
experimental work, and since the chinch bug problem
especially severe in some of the more southern parts
Florida, the higher dosages may be needed. The amou
of insecticide per unit area is given in the control cha
4. Applying the insecticide: It is important to apple
the insecticide in a large amount of water in order to soak
the thick mats of St. Augustinegrass.
For power sprayers use at least 15 gallons of spray
per 1,000 square feet. Many commercial spray operators
use considerably more.
Jar attachments to garden hoses are excellent tools for
home owners to use. Use the type designed to apply liquid
fertilizers, and which will require 15 to 20 gallons of water
passing through the hose to empty the jar. Put the amount
of insecticide in 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). Pass the spray back and forth over the
area in a cross-hatched pattern to get even coverage.
A sprinkling can is satisfactory for use on small areas.
In a 2-gallon sprinkling can put 1% to 3 tablespoons of
DDT emulsion concentrate, 1 to 2 teaspoons of Diazinon,
or 2 to 4 teaspoons of V-C 13, stir well and apply the 2
gallons carefully over 50 square feet of lawn.
Sprays applied as described above usually result in
lawns being free from chinch bug damage for several
weeks; in some instances the lawn may not be troubled
again for months. While the general approach to chinch
bug control is to be vigilant in watching for their appear-
ance and to treat promptly when they do appear, some
people prefer to use a preventive spray program. Such
a program would call for the first spray to be applied in
March in southern Florida and for subsequent sprays at
about 6-week intervals. In average years, the initial spray
can be made later as one moves farther northward, so that
in the northern third of the state late May would usually
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, 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. This habit makes them difficult to find.
The newly hatched caterpillars cause very little visible
damage to grass. It is not until they are nearly full-
grown "worms" that their feeding becomes very notice-
able, 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 in the blades and the blades
are eaten back unevenly. The foliage may be almost com-
pletely stripped off in patches, and these close-cropped
areas have a yellowish to brownish appearance.
A good way to look for sod webworms is to part the
grass and look for the small green "worm" curled up on
the soil and for small green pellets of frass or excrement.
A flashlight used at night will reveal the caterpillars
working up among the grass foliage.
Armyworms grow to about 1% inches in length, or
about twice the length of the full-grown sod webworm.
They do not rest in a curled position and are active during
Toxaphene or DDT is excellent. However, a number
of other materials, including BHC and dieldrin, give satis-
factory control. The lawn spray mixtures commonly sold
by garden supply stores contain one or more of these
insecticides and are effective against these chewing cater-
pillars. Dusts and granules can be used effectively.
MOLE-CRICKETS, BILLBUGS, WHITE GRUBS
The damaging stages of this group of insects are soil
dwellers that feed on roots. Mole-crickets make burrows
like tiny mole tunnels. 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 is becoming more important as a
pest of grass in Florida, especially on Zoysiagrass. As
the name suggests, the adult beetle has a bill or snout.
The larva or grub, which is legless and grows to about
% 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
Several species of white grubs damage grass. These
pests are the larval stage of beetles such as May or June
beetles. Unlike the billbug, they have three pairs of small
legs near the head end. They are generally distributed
in Florida, but are not considered to be major pests of
The method of control is similar for all of these soil
dwelling pests. Again, the hose attachment sprayer dis-
cussed 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.
Several kinds of scales may infest lawn grasses in
Florida. Rhodesgrass scale appears to be the most im-
portant, but Bermudagrass scale and sugarcane scale may
be troublesome. They are frequently overlooked because
they are so inconspicuous.
Grass injured by scales has an off-color, yellowish ap-
pearance and may be killed. If other insects are not
found in yellowed and thin areas of grass that will not
respond to fertilizer and water, inspect the grass closely
These are difficult insects with which to cope, and
home owners do not frequently attempt their control.
The best choice for home owner use would be a mixture
of malathion plus a summer oil emulsion. Mix at the
rates given in the chart and wet the grass thoroughly.
A single application usually brings improvement in the
appearance of the grass, but one or more repeat applica-
tions at about 3-week intervals are needed to reduce the
scale population substantially.
Parathion is an excellent insecticide for control of
chinch bugs, sod webworms and several other lawn pests,
but only properly equipped and trained operators should
use it. It is not recommended for use by home owners,
and it generally is not needed if the other materials in
the control chart are properly applied. Parathion has
given good control of chinch bugs at the rate of Y pound
of 15% wettable powder or 1 fluid ounce of 42% emulsi-
fiable concentrate or equivalent per 1,000 square feet of
lawn. Some turf nurserymen add parathion at this dosage
to the recommended insecticides for billbugs in the first
of a series of sprays for rapid initial kill.
Parathion has given best results in scale control so far.
About % pint of 42% emulsifiable concentrate (or equiva-
lent) or 2 pounds of 15% wettable powder can be mixed
with 2 quarts of summer oil emulsion in 100 gallons of
water and applied so as to wet the grass thoroughly. I
a series of sprays for Rhodesgrass scale, it would be bette
to add the oil to the spray every other time because o
the danger of the oil emulsion causing the grass to tu
Insecticides are poisons and should be handled as such
Read completely the manufacturer's label on the contain
before opening, and follow the directions and precaution
given. Parathion is especially toxic to man and his pet
Keep poisons stored in the original container away fro
children and pets. Do not breathe mists or fumes, or spi
sprays on the skin. Wash hands after using insecticide
Wear rubber gloves when handling and applying insect
i I CONTROL (See text for important points on applying insecticides)
PEST DESCRIPTION LIFE HISTORY INJURY Pesticide Amounts
Adults about 1/5 inch long, black Sometimes adults hibernate in Of the lawn grasses, only St. Per 500 Sq. Ft.
Chinch Bug with white patches on wings winter in Northern Fla., but all Augustinegrass is seriously in- (for qt. size hose Per 5,000
which are folded over back. stages present year around in jured. Bugs inject a slender, 25% DDT emulsifiable con- sprayer) Sq. Ft.
(Blissus insularis Barber) Young (nymphs) range from most of the state. Eggs laid in piercing beak into grass and centrate ...................................... 1 2 cups (% 1 pint) 2% 5 quarts
1/20 inch long to nearly adult leaf sheaths and pushed into suck plant juices; possibly saliva 50% DDT wettable powder ........1 2 cups (% % lb.) 2% 5 pounds
size, are reddish with white soft soil and other protected is toxic to grass. Typical in- 25% Diazinon emulsifiable
band across back. places. In summer hatch 1 1% jury shows as a patch with concentrate ............................. 3 6 tablespoons 1 2 pints
weeks; young develop to adults brown, dead center and yellow- 75% V-C 13 emulsifiable con-
in about 5 weeks; adults may ish margin. centrate ............................... 6- 12 tablespoons 1-2 quarts
live many weeks. Parathion-see text
Caterpillar grows to % inch in Adults lay eggs among grass. The caterpillars are the only Per 1,000 Sq. Ft.
Sod Webworms length; greenish. Adults are Eggs hatch in about 1 week. damaging stage. They devour (for qt. size hose Per 100
dingy brown moths with wing- Larvae feed on grass blades and the foliage, feeding only at Toxaphene emulsifiable concen- sprayer) Gallons
(principally Pachyzancla spread about % inch. grow large enough to cause de- night. Damage usually seen in trate (6 lbs. per gallon) ........ 1 cup (% pint)* 2% pints*
phaeopteralis (Guenee)) struction within 2 weeks. Much patches. Grass blades notched 40% toxaphene wettable powder 1% cups 4 pounds
damage next 1 1% weeks till on sides and chewed back rag- 25% DDT emulsifiable con-
pupation. Adult emerges from gedly. Grass may die if foliage centrate ................................... 1% cups (% pint) 4 quarts
pupal stage in about 1 week. stripped off in hot, dry weather. 50% DDT wettable powder ........... 1% cups 4 pounds
They complete their life cycle in Parathion-see text
5-6 weeks and have several Dusts: Apply 10% toxaphene dust to the grass at the rate
generations a year. of 1 lb. per 1,000 square feet, or apply 5% DDT dust at the rate
of 2- 2% lbs. per 1,000 square feet.
Caterpillar grows to 1% inches Moth lays eggs on grass and on Caterpillars chew the grass
Armyworms long. Greenish when small; almost any object near lawns. blades. Turf appears ragged, Control is the same as for sod webworms.
dark brown when full grown. Development is much like sod and foliage may be stripped off.
principally fall armyworm, Has a light mid-stripe along webworm. Armyworms pupate Feed during the day, and dam-
Laphygma frugiperda back; darker bands on each side in the soil, however, age often not in as definite
(J. E. Smith)) of mid-stripe. Mid-stripe ends patches as that of sod web-
in inverted V on head. worms.
Odd-looking crickets growing to In spring, adult places eggs in Make burrows in soil. Loosen Per 500 Sq. Ft.
Mole-Crickets 1% inches long. Have velvety underground cells. Eggs hatch soil, disturb and cut off roots. (for qt. size hose Per 5,000
appearance from covering of in 1%-2 weeks in warm weather. They like to work in soft, newly sprayer) Sq. Ft.
uthern mole-cricket, Scap- fine, brown hairs. Front legs Become adults by fall. planted areas, but can be seri- 1.5 2% chlordane bait .............. 1 2 pounds 10- 20 pounds
teriscus acletus R & H; flattened and adapted for bur- ous in established turf as well. 23% aldrin or heptachlor emul-
uerto Rican mole-cricket, rowing, sifiable concentrate ...... ........ 6 tablespoons 1 quart
S. vicinus Scudd.) 25% heptachlor or aldrin wet-
table powder .......................... 1 cup (% pound) 2 pounds
Chlordane emulsifiable concen-
trate (8 lbs. per gallon) ........ cup* 1% pints*
40- 50% chlordane wettable
powder .................................... 1 cup (% pound) 2% pounds
Larvae are fat grubs which lie Adults lay eggs in the soil. Grubs damage grass by devour-
White Grubs in C-shaped position. Whitish Grubs which hatch out live in ing roots. Yellowish areas de- Control is the same as for mole-crickets (not baits).
in color with dark areas at rear. the soil and feed on roots. Dif- velop in turf, and grass can be
(May or June beetles, Brownish head. Adults are ferent species take varying killed. In severe cases, roots
llophaga spp.; Green June beetles, times to go through life cycle- pruned off to extent that the
etle, Cotinis nitida (L); 1 to 4 years. Adults do not feed turf mat can be rolled back like
Cyclocephala spp.) on grass. a carpet.
The larva or grub grows to % Eggs are laid in leaf sheaths or Damage is caused by devouring
Billbugs to '% inch long. Body is white top of crown of grass plant. of the roots. Have been most Control is the same as for mole-crickets (not baits).
and head yellowish-brown. This Hatch in 3- 10 days. Grubs severe in recent years on Zoysia-
ncipally Calendra venatus grub is legless. Adults are dark work down to roots and live grass, but may attack others as
vestita (Chttn.)) brown or black, and about % underground. Are destructive well.
inch long. They have a long for about a month before pupat-
snout or "bill." ing in cells in soil. Probably
several generations a year in
Middle and South Florida.
Grows to about % inch diam- Adult female lays eggs within Scales suck out plant juices via Per 1,000 Sq. Ft.
Scales eter. Body of scale is dark, and the cottony covering. From the a long, slender beak. Infested (for qt. size hose Per 100
roughly spherical, but covered eggs a crawling stage emerges grass turns yellow, and if the Malathion emulsifiable concen- sprayer) Gallons
cipally Rhodesgrass scale, with white, cottony secretion. and moves out through grass insects are not controlled, the trate (5 lbs. per gallon), or mix % cup,* or mix 3 pints,*
tonina graminis Mask.) They are found at joints of before settling to feed. Once grass may be killed. 25% malathion wettable 2 cups, plus or 4 5 pounds,
grass runners, at crown of plants they are settled down to feed, powder, plus 80 90% sum- % cup plus 2 quarts
that do not "run," at soil level they begin to secrete their cover- mer oil emulsion
and in loose soil at surface, ing, and never move again. Parathion plus oil-see text
equivalent amounts of other concentrations of liquid formulations may be substituted.
Luid Measures: 3 teaspoons=l tables oon 2 --
cu 2 cups=l pint 2 pints=1 quart 4 quarts=l gallon.