Wood ticks : how to control them in infested places

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Diseases
They
Spread

Insecticides

Repellents

Ticks

in Homes

THE AMERICAN DOG TICK: ADULT
FEMALE. GREATLY ENLARGED.

LEAFLET = -U. S. DEPARTMENT
No. 387 OF AGRICULTURE

~WO00D TICKS how to control them in infested places

The term “wood ticks” is applied to several species of
ticks so similar in appearance and habits that few persons
can tell one from another.

Wood ticks feed on the blood of animals, and may bite
people. Their bites are painful. and some of them carry
diseases. They cause economic losses among farm
animals and are serious pests of dogs.

The ticks infest wooded or brushy areas and grassy
fields. They are often found in recreational areas and
lawns. and are sometimes found in homes in small num-
bers. When ticks are found in relatively large numbers
in homes. they are not wood ticks; see section “Ticks
in Homes” in this publication. Wood ticks are an annoy-
ance and a health hazard to farmers, woodsmen, and mili-
tary personnel; to campers, picnickers, vacationers, hunt-
ers. and hikers; and to persons who live in rural and
suburban areas.

You can control wood ticks by applying insecticides.
You can protect yourself by applying a repellent to your
clothing before entering an infested area.

Species .. . Nature of Injury

The more common species of wood ticks are the Rocky
Mountain wood tick.’ the American dog tick,” the lone
star tick,* and the black-legged tick.*

The Rocky Mountain wood tick and the American dog
tick transmit Rocky Mountain spotted fever and tularemia
(rabbit fever), which are diseases of man, and anaplas-
mosis, a disease of cattle.

Adults of these ticks can also cause a form of paralysis
in animals and people in rare instances when they attach
over the spinal cord or at the base of the skull.

The lone star tick can transmit Rocky Mountain
spotted fever, tularemia, and Bullis fever. The black-
legged tick transmits piroplasmosis, a disease of dogs, and
anaplasmosis.

Life Stages . . . Appearance

Wood ticks go through four stages of development—
egg, larva, nymph, and adult.

The eggs are usually laid in masses in thick clumps of
erass. Each female lays only one mass, which contains
3,000 to 6,000 eggs.

The eggs hatch into larvae, which attach themselves to
host animals. In a few davs the larvae fill themselves
with blood, drop to the ground, and shed their skins, or
molt. The larvae have become nymphs.

The nymphs attach themselves to host animals, become
engorged with blood in a few days, and drop to the ground
and molt. The nymphs have become adults.

Adults of both sexes attach themselves to host animals.
They mate on-the hosts. They become engorged with

* Dermacentor andersoni. °D. variabilis.

> Amblyomma americanum.

blood in 5 to 13 days. After engorgement. the females
drop to the ground, lay their eggs. and die.

The larvae are about '40 inch long when unfed. En-
gorged larvae and unfed nymphs are about 46 inch long.
Engorged nymphs and unfed adults are about “16 inch
long. and engorged females may be % inch long. The
males do not enlieee as they feed.

The adults of the Rocky Mountain wood tick and the
American dog tick are indistinguishable. The hard
shields on their backs are liberally spotted or streaked
with white. The adult of the lone star tick is marked on
the back with a small white dot or two small crescents.
The adult of the black-legged tick has black legs, and has
a shiny black shield on the back.

Where They Occur .. . Habits

The Rocky Mountain wood tick occurs in most of
the Western States. It is most common in the Rocky
Mountain region.

Only the adult ticks bite people. The larvae and
nymphs feed on small animals. especially rodents.

The life cycle of this tick usually extends over a period
of 2 years. All stages of the tick are abundant and active
during the summer. Nymphs and adults survive over
winter.

The American dog tick occurs throughout the United
States, except in the Rocky Mountain region. It is most
abundant in coastal areas and in the Mississippi Valley.

The larvae and nymphs feed largely on rodents. The
adults feed on dogs. cattle, and “other large animals.
They will bite people.

In the northern part of the United States the adult ticks
are abundant in the spring and early summer; few are
encountered after August 1. In the southern part of the
United States their activity is less sharply influenced by
change of season.

The lone star tick is most common in the coastal
States from North Carolina to Texas, and in the
Mississippi Valley.

The ticks are usually well distributed over whatever
area they infest, but they occur in the greatest numbers
in habitual resting places of animals or in layers of leaves
or duff in wooded areas.

The larvae and nymphs feed on most mammals and
ground-nesting birds. The adults feed on deer. cattle.
horses, hogs, and many small animals. Larvae. nymphs.
and adults will bite people.

The larvae (often called seed ticks) crawl up vege-
tation near the spot where the eggs hatched. They collect
in clusters. The number of larvae in a cluster ranges
from fewer than:a hundred to more'than a thousand. All
or most of the larvae in a cluster cling to a person or
animal that brushes against them. Many of the larvae

‘Ixodes ricinus scapularis.

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will bite. and are easy to locate and remove. Finding
and removing those that do not bite is a tedious task.
Bites of larvae are irritating for as long as 10 days.

Nymphs and adults usually congregate in ground litter,
or on vegetation. They cling to passing animals or crawl
over the ground to attack hosts that lie or stand nearby.

Nymphs and adults are most abundant from March to
July: some may be encountered until September. Larvae
are most abundant from July to September.

The black-legged tick is found along the east coast.

The larvae and nymphs feed on various rodents and
reptiles. The adults feed on deer. cattle. sheep. hogs.
dogs. and other large animals. They will bite people.
Long mouth parts make their bites especially painful.

The adults are most abundant in the fall and early
winter.

American dog ticks and black-legged ticks usually con-
gregate along game trails, paths, and roadways. where
they wait on vegetation and attach themselves to animals
and people that pass by.

Larvae and nymphs of wood ticks may live for a year
without feeding, and the adults for 2 years.

Control in Outdoor Areas

Control wood ticks in infested outdoor areas by using
DDT. toxaphene. chlordane. or dieldrin. DDT is the
insecticide most widely used for this purpose.

Lindane gives good initial control. but it usually remains
effective for a shorter time than DDT, toxaphene, chlor-
dane, or dieldrin.

The selected insecticide can be applied as a spray or
as a dust. Sprays are sometimes more difficult to apply
than dusts. especially if the area to be treated is large and
the growth of brush is heavy.

RATE OF APPLICATION
Dusts

Dusts are sold in different strengths and are ready to
use when purchased.

To treat lawns or similar areas where the vegetation
and ground cover are relatively thin. apply a 10-percent
DDT dust, or a 5- or 10-percent toxaphene, chlordane, or
dieldrin dust: apply it at the rate of 20 to 25 pounds per
acre. To treat wooded or brushy areas. apply 40 pounds
of one of these dusts per acre.

Apply lindane at the rate of 0.2 to 0.4 pound per acre.
The amount of a commercial product that you must apply
in order to get the proper dosage depends on the per-
centage of active ingredient in the product. For example.
you would apply 1-percent lindane dust at the rate of 20
to 40 pounds per acre.

Sprays

Apply DDT. toxaphene, chlordane. or dieldrin in sprays
at the rate of 1 to 2 pounds of the actual insecticide per
acre. Apply lindane at the rate of 0.1 to 0.2 pound per
acre.

PREPARING A SPRAY

To prepare a spray, mix an emulsifiable concentrate or
a wettable powder with water. (Do not use oil solutions;
they will burn the vegetation.) The amount of concen-
trate or powder that you must use to get the proper dosage
depends on the percentage of active ingredient in the
product you buy. The table below shows ‘the percentages
most commonly found in retail products and the amount
of each product that is needed in a spray mixture prepared
for treating | acre.

|
its : : | Amount of purchased
Insecticides, and forms in which | product to mix with

they may be purchased 95 wallonsohntee

DDT, TOXAPHENE, CHLORDANE,
AND DIELDRIN |

Emulsifiable concentrate:

40-percent=—2 = === eee ee | 3 quarts.
o0= percents" == 2 = eee noes | 2. quarts.
6o-percent==== = eee eee | 1% quarts.
Wettable powder: |
25-percent=2=-2e asses & ee ele 8 pounds.
50-percent= ssa 5= see uee Coens | 4 pounds.
LINDANE |
Emulsifiable concentrate: |
20-percent == a sees eee | 1 pints.
25-percenta= = see Sewers aa ae ] pint.
Wettable powder: |
25-percent- 2. == le pounee

The amount of water needed depends on the per-acre
output of your spraying equipment and the kind of vege-
tation on the area to be sprayed. It takes 15 to 25 sallons
of spray per acre to spray lawns or similar areas, and 50
gallons or more per acre for thorough coverage of wooded
or brushy areas.

APPLYING THE INSECTICIDE

Before applying the insecticide. make a quick survey
by dragging a white flannel cloth over the ground and
vegetation. Use a square yard of white flannel cloth
tacked along the front edge to a stick. Examine it for
wood ticks frequently. This will show whether you need
to treat the entire area or only those parts of the area
where ticks may be concentrated.

Apply the insecticide as soon as ticks become annoying.
Apply it to the ground, to surface litter, and to vegetation.
Treat the vegetation to a height of about 2 feet.

One application may be effective for an entire season:
but if ticks again become annoying, it may be necessary
to repeat the treatment.

If you spray. wet the ground, litter, and vegetation
thoroughly. Shake the container occasionally to ke sep the
insecticide well mixed with the water. If you dust. be
sure to get the dust well distributed.

Do not apply insecticides for tick control to crops or
grazing areas.

Dusting woodland litter to kill lone star ticks.
The applicator is a rotary hand duster.

To kill American dog ticks and black-legged ticks. spray
or dust a strip 20 to 30 feet wide on each side of roads
and paths. To kill other species of ticks, treat the entire
infested area. (If a survey shows that lone star ticks are
concentrated in thickets. treat only those places.)

On lawns and grounds up to an acre or two, or along
roads and paths. apply the insecticide with a 2- or 3-gallon
hand-pressure sprayer or a plunger- or rotary-type hand
duster. If the area is large or the roads or paths extend
over long distances. use a power sprayer or power duster.

Aircraft can be used to treat some large areas of general
infestation. Large area treatments may prove hazardous
to wildlife. Do not treat unless necessary to protect
humans from ticks and the diseases they carry.

Using Repellents

The mosquito repellents deet (diethyltoluamide), di-
methyl phthalate, and ethylhexanediol. applied as clothing
impregnants, will provide some protection against wood
ticks. If you wear socks. shirt. and trousers impregnated
with one of these materials. you can expect about 75-
percent protection from ticks.

Better protection can be obtained with another repellent,
Indalone, but it is not widely available.

Use the selected repellent in a solution or an emulsion.
A 5-percent solution or emulsion will provide an effective
deposit on ordinary cotton khaki, denim, or light wool
clothing. About 3 pints of solution or emulsion will
impregnate an outfit of socks. shirt. and trousers.

You can make a 5-percent solution by mixing a repel-
lent with acetone or a dry-cleaning solvent at the rate of
1 ounce of repellent to 1 pint of acetone or solvent.

You can make a 5-percent emulsion by mixing 1 ounce
of repellent with 1 pint of water and 2 ounces of an

Spraying vegetation to kill American dog ticks.
The applicator is a compressed-air sprayer.

emulsifier such as Tween 80 or Triton X—100 or 1 ounce
of laundry soap.

Dissolve the emulsifier or soap in the water and add the
repellent slowly while stirring the mixture vigorously.
(Synthetic household detergents are not suitable for mak-
ing emulsions but most laundry soaps are satisfactory.)

Dip the clothing into the repellent mixture or pour the
mixture over the clothing. Then wring out the clothing
by hand. Let it dry thoroughly before wearing it. The
repellent will remain effective for about a week unless the
clothing gets wet. Wash and re-treat clothing at weekly
intervals.

Do not treat rayon and nylon fabrics with repellent
solutions or emulsions. Nylon is nonabsorbent and will
not retain enough repellent to be effective. Some types of
rayon may be damaged by the repellents.

Ticks in Homes

Although wood ticks seldom occur in homes in numbers
that make control measures necessary, other ticks. chiefly
the brown dog tick (Rhipicephalus sanguineus ). will infest
homes and other buildings if dogs are present.

The brown dog tick passes through the same stages as
the wood ticks. In homes, the eggs and engorged ticks
may be found in cracks. behind curtains. and under
furniture or rugs. The tick will survive the winter out of
doors in the most southerly States. but in most of the
country it survives only in heated buildings. It seldom
bites people.

Soft ticks belonging to the genus Ornithodoros some-
times occur in homes in the Western and Southwestern
States. They are extremely painful biters and several

species transmit the germs of relapsing fever.

CONTROL

Apply a residual spray to control brown dog ticks and
soft ticks in the home. Dusts can be used. but they are
harder to apply and are unsightly in exposed places.

Household spray formulations come in_ different
strengths and are ready to use when purchased.

Use a spray that contains either 5 percent of DDT,
2 percent of malathion or 2 percent of chlordane, 1 per-
cent of lindane, or a combination of DDT and chlordane
or activated pyrethrum.

Apply with a hand sprayer or household sprayer.
Apply the spray thoroughly to baseboards, around door
and window mouldings, behind pictures, under furniture,
around the edges of rugs, on curtains and draperies. and
in all cracks.

For several weeks the residue left by the spray kills ticks
that come in contact with it. One application is usually
sufficient. but if ticks are numerous after the second or
third week, repeat the treatment.

Precautions

Handle insecticides with care. Most of them are likely
to poison people and animals if they are handled
carelessly.

Store insecticides where children, pets, and livestock
cannot reach them. Label containers plainly.

Avoid inhaling sprays and dusts. and do not expose the
skin to them more than is necessary. If you spill the
material on skin or clothing. or get wet with the spray.
change clothing and bathe immediately.

Do not apply these insecticides to crops, grazing areas.
or livestock.

To avoid killing fish when applying insecticides near
streams. lakes, or ponds, do not let excessive amounts
get in the water. Be especially careful when using dieldrin
or toxaphene near fish-bearing waters.

Do not contaminate water supplies, such as wells and
cisterns.

Ticks on Animals

For information about control of ticks on animals,
write to the U. S. Department of Agriculture, Washington.
D.C., 20250.

Prepared by the Entomology Research Division,
Agricultural Research Service

Washington, D.C. Issued June 1955
Slightly revised October 1963

yy U.S. GOVERNMENT PRINTING OFFICE : 1963—O-697-548

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