

The most common ticks found in Delaware are the American dog tick,

the brown dog tick and the black-legged tick. The American dog

tick, often called the eastern wood tick,  rarely invades the home

in large numbers. However, the brown dog tick can become a serious

household pest. The black-legged tick or deer tick will bite humans

as well as domestic animals, but it is generally an outdoor tick.



Life history and habits



Ticks have a four-stage life cycle. The egg hatches into a

six-legged larva, or seed tick. After a blood meal, the larva molts

(sheds its skin) and becomes an eight-legged nymph. After another

blood meal, the nymph molts and becomes an adult. The adult female

then attaches to a warm-blooded animal, engorge on blood, mates,

leaves the host animal, deposits several thousand eggs and dies.

Adults can live a year or more without feeding, but they must feed

before mating.



The American dog tick is widely distributed east of the Rocky

Mountains and on the Pacific coast. Dogs are the preferred host of

the adult tick, but humans and many other animals are frequently

attacked. Because larvae and nymphs prefer to feed on mice, rats

and rabbits, this tick does not become established as a household

pest. The American dog tick is responsible for spreading Rocky

Mountain spotted fever.



The brown dog tick differs from the American dog tick primarily in

its feeding habits. It feeds almost exclusively on dogs and rarely

attacks humans. In all stages it is commonly found on the ears, the

back of the neck, and between the toes of dogs. After feeding, the

ticks drop off the host and conceal themselves in any available

crack or crevice. Because of their strong tendency to climb, they

are often found on furniture and behind window frames and moldings.



A smaller tick known as the black-legged tick has been found on

humans and pets. It is associated with areas supporting large

rodent rodents as well as deer. Although smaller than the dog tick,

TICKS
its bite is painful because its mouth parts have tiny barbs to
anchor it securely. The barbs make removal difficult; they often
remain in the skin, causing local infection. This tick is a carrier
of a Lyme disease pathogen that causes arthritis-type symptoms and,
if not treated, can affect the liver, heart and lungs.

Identification of a tick found on a person or pet is often
difficult. If the tick has been feeding and is engorged,
identification is even more difficult. The American dog tick can be
distinguished from the brown dog tick by the white mottled shield
(scutum) on its back, behind the head. Brown dog ticks have a
shield but it lacks the lighter markings. The black-legged tick
also lacks a color pattern and it is distinctly smaller being no
larger than the period at the end of this sentence. trousers. Tuck
trousers into boots or socks. Search all areas of your body at
least daily if you frequent tick-infested areas.

Black-legged tick control should eliminate the nymphs since this
stage is most likely to transmit Lyme disease. The larval stage is
incredibly small--no larger than the period at the end of this
sentence. Sprays with carbaryl, diazinon, and Dursban provide some
control but don't take such measures unless infestations are
confirmed. Always use a repellent and check for ticks on your body.

Tick removal

The best method to remove ticks from a person or pets is with a
slow, steady pull. Get the capitulum (mouth parts) out with the
rest of the tick. Tweezers work well, especially in removing black-
legged ticks. Place the tweezers as close to the point of
attachment as possible and pull steadily away from the skin. An
antiseptic will prevent infection and reduce irritation. We can't
recommend using fingernail polish, chloroform, ether, gasoline,
kerosene, a hot match or needle or a glowing cigarette. These
methods can cause more serious injury than the bite itself.

Protecting pets

Dogs and cats that roam outside should be inspected periodically
for ticks. Remove attached and/or engorged ticks. Where ticks
occur, pet collars impregnated with tick pesticides should be used
routinely. Heavily infested animals can be treated by a
veterinarian or an insecticide dust or shampoo effective for tick
control. Carbaryl, pyrethrin with piperonal butoxide or a synthetic
pyrethroid such as resmethrin or permethrin are available.

Controlling the American dog tick

American dog ticks are active in Delaware from late May to early
August and can be controlled outdoors by keeping grass and weeds
mowed and low-lying shrubs cut back. The same cultural practice is
helpful around campgrounds, hiking trails and other outdoor use
areas. Heavy infestations may need more attention. Spraying or
dusting infested areas with one of the following Insecticides:
malathion, carbaryl, diazinon or Dursban may be needed.

Controlling the brown dog tick

Brown dog tick infestations in the home often require the services
of an experienced pest control operator. Sometimes homeowners can
control light infestations with the proper use of an approved
insecticides. Give special attention to the dog's sleeping
quarters, as well as chairs and other places the dog frequents.

Treat all cracks and crevices with carbaryl or diazinon, moldings,
window and door frames, and similar places where ticks might hide. 

Controlling the black-legged tick

The same insecticides used to control dog ticks are also effective
for black-legged ticks. Since this tick is associated with
wildlife, hunters, hikers and those involved in outdoor activities
should consider using a repellent. Repellents containing DEET
(dimethyl-meta-toulamide) and/or dimethyl phthalate help prevent
tick attachment. Apply to exposed skin, socks and lower portions of
trousers. Tuck trousers into boots or socks. Search all areas of
you body at least daily if you frequent tick-infested areas.

Control in dwellings

Engorged ticks may be brought indoors by humans, dogs, or cats,
leading to infestation of homes, kennels, and animal hospitals. The
brown dog tick (Rhipicephalus sanguineus) can complete its entire
life cycle in a domestic setting, using dogs as a primary host. For
this reason, this species can become an significant nuisance in
houses, apartments, kennels, and veterinary facilities. Eggs may be
laid in cracks and crevices, upholstered furniture, and under
carpeting. Larval and nymphal ticks may conceal themselves in those
locations as well as behind light switches and picture frames.

For proper chemical control of brown dog ticks in kennels and
veterinary facilities, certain areas (e.g., the cracks in kennel
floors and walls, roofs, and ceilings of porches) should receive
special attention. Diazinon can be used as a residual spray. A
nonresidual fog composed of pyrethrin and Vapona can also be
employed for pet sleeping quarters and domestic dwellings. Cat
kennels and sleeping quarters should be dusted with carbaryl
following a thorough scrubbing. Open premises of dog kennels, runs,
and yards can be treated effectively using chlorfenvinphos.

If homes or apartments are infested, rugs and carpets can be
treated with a dust formulation containing pyrethrin or allethrin;
the latter may also be used for upholstered furniture. An indoor
fogger containing methoprene and permethrin is also useful for
space spraying domestic dwellings.

Control outdoors, in campgrounds, and on hiking trails

Outdoor activities often bring campers, picnickers, hikers, bird
watchers and others in close proximity to tick-infested areas. To
establish "tick-free zones" in recreational areas (tick contact may
be greatly reduced, but not eliminated), it is possible to intermix
simple cultural practices with pesticide use to drastically reduce
sites of tick contact. To do so, low-lying vegetation, shrubs and
grasses surrounding campgrounds or backyards should be close
cropped or mowed to discourage tick movement and nesting. Dursban,
carbaryl, or diazinon should then be broadcast into the surrounding
vegetation to establish an effective chemical barrier. A similar
process, but on a smaller scale, can be followed for well-defined
hiking trails.

Researchers have found evidence that in areas where the deer tick
(vector of Lyme disease) Is endemic, it may be present in home
lawns. Workers have shown that by using registered pesticides at
the proper time, tick contact may be greatly reduced. spraying does
not guarantee that ticks will not be present. Self-protection
should always be practiced by dressing appropriately, using
repellents when in potentially tick-infested areas, and checking
dally for the presence of ticks, removing them if found.

Control should be aimed at the nymphal stage, which is the most
likely stage to transmit the disease to humans. One application of
a pesticide should be made at nymphal population peak. Research
indicates that In Westchester County, New York, peak populations
occur during the last week In May. (Data are lacking for other
areas.) A second application toward the end of the nymphal stage,
in late July to early August, is also suggested. Tests using
carbaryl, diazinon, and Dursban were all effective in reducing deer
tick populations.

"Damminix" is another control device that presents cotton balls
treated with permethrin in cardboard tubes. Proper placement of the
tubes is essential. Mice take the cotton balls and use them in
building nests. The mice are therefore exposed to enough pesticide
to control the ticks that try to feed on them. Damminix is reported
to be effective In reducing larval tick numbers and may have a
place in an integrated tick management program.

Commercial treatment of residential premises for tick control must
be done by certified applicators.

Dewey M. Caron 
University of Delaware 
Cooperative Extension Entomologist
11/90

To the best of our knowledge, all recommendations in this are in
accordance with those on product labels. However, if there is
disagreement between recommendations in this bulletin and what is
stated on the label, always follow the label directions.
.
