Indoor Tick Control
Generally, ticks are not a serious indoor pest. Most all tick species cannot live very long inside, as it is too dry for them. Ticks require a habitat with a very high humidity (>80%). Therefore, they may enter your house on your pets or on your clothing, but they aren't likely to become established. A good exception is the brown dog tick, Rhipicephalus sanguineous. The best way to prevent ticks from entering your home is by thoroughly examining yourself and your pets before you go inside - especially, if you've been in tick habitat. After you remove your clothes it is often a good idea to put them directly into the washer rather than on the floor or in a hamper. Fine brushes are very effective at removing crawling ticks and finding attached ones. So, it can be a good idea to brush your dog or cat once a day.
There are a variety of pesticides that you can use to control ticks in general. Most any good hardware store or Agway or even large stores like K-mart will sell pesticides. I would recommend Pyrethrins or Permethrins if you want a relatively safe chemical. Another good one is Chlorpyrifos (Dursban). Of course, you can always use the heavy duty stuff - Diaznon, Malathion. Try to identify the ticks if they're indoors. Brown dog ticks are small (about 1/8 inch) and a uniform reddish brown. If you have these you will most definitely have to treat inside your house. To control any ticks indoors, first, vacuum thoroughly (especially cracks and crevices near dog resting spots); then treat with a properly labeled acaricide. Several pesticides are labeled for tick control including allethrin, bendiocarb, carbaryl, chlorpyrifos, esfenvalerate, and permethrin (or other pyrethrins). If you have any other tick species indoors, it's better to just try and keep them out with daily tick checks. Repellents can also be used to help keep the ticks off yourself and your pets. Products with 20 - 25% DEET are effective. Generally higher concentrations of DEET are not advised because they provide no better repellency but can lead to more serious skin reactions.
Backyard Tick Control
A typical lawn is not considered good tick habitat, especially for deer ticks. Deer ticks are very susceptable to dessication, and the typical well-mowed lawn, receiving lots of direct sunlight, is not conducive to maintaining high tick populations. The American dog tick, however, is more hardy and able to survive well in lawns and fields. None the less, most control efforts should be focused on the edge of your lawn, especially if its adjacent to wooded areas or other habitats harboring tick populations. There are several options for tick control in your yard. First, you can try altering your yard's landscape such that it is not tick "friendly". In other words, you can reduce mouse and other small mammal nesting sites - such as brush and wood piles. Also, you can fence the yard so that deer and other tick hosts can not walk through it. Deer certainly carry ticks on them, and it is possible that engorged female ticks could get deposited in your yard via grazing deer. You can cut back overhanging limbs or put "barriers" between your yard and the wooded areas. For example, a 2 - 5 foot wide stripe of wood chips or decorative stones can help to prevent ticks from entering your lawn. Also, this can serve as a physical reminder to yourself that you're entering tick habitat.
If you can't or its impractical to implement some of the habitat manipulations suggested above, you may have to resort to applying acaricides. However, you don't necessarily have to treat the entire yard, as suggested above. First of all, a perimeter treatment around the house itself is probably not that effective. The only way ticks will enter your home is either on you or your pets. They do very little horizontal migration on the ground. The idea of a perimeter spraying is to keep the insects from crawling into your house. Ticks won't do that by nature. Again, control efforts are best focused at your yard's edge, especially where your yard borders on woods. The exception would be if you have an existing infestation of dog ticks, for example. Generally, spraying around the outside edges of your lawn, about 5 - 10 feet in from the wood's edge. Again, very few ticks are found in the middle of a well-maintained lawn that receives lots of direct sunlight because this type of area would most likely desiccate the ticks. Consequently, if you have these types of open areas, it not effective to spray them unless you know that the ticks are existing throughout your lawn. However, consideration should be given to areas of the yard that get lots of shade, have bushes or other landscaping features, and have areas suitable for small mammal harborage. You can use the same chemicals as listed above. However, you may want to consider a granular or wettable powder formulation as these tend to give better penetration into the leaf litter and better residual protection. If you do spray your yard and you have pets be sure to keep them off the treated areas for about 24 hrs.
Alternative Control Measures
Ticks have many natural predators in the environment. Several wasp species will parasitize ticks, one species in particular (Ixodiphagus hookeri) has been studied quite extensively. The female wasp lays her eggs inside an engorged nymph. After the wasp eggs hatch, the larvae feed on the tick's internal tissues and then emerge, killing the tick in the process. Many species of spiders will also eat ticks if they can find them. Also, there are a variety of fungi and nematodes that also feed on and kill ticks while they are molting in the soil. Some of these organisms (in particular the fungus, Metarhizium anisopliae) are beginning to be intensely studied for their pathogenic effects. Birds will certainly eat ticks that they encounter during foraging. The most notable is the helmeted guineafowl, Numida meleagris. Studies have shown that these birds will readily forage on ticks (engorged and nonengorged).
Unfortunately, none of these organisms have any real success in controlling tick populations. In fact, some of them are only found in areas where ticks are super abundant. Hence, biological control agents are not yet ready for widespread use in tick management programs. The thought in some recent studies has been to augment some of these natural predators with other natural enemies. However, these studies have also met with varting degrees of sucess. Ideally, a well-designed tick control strategy would employ some use of natural enemies, mixed with targeted acaricide application, habitat modification and perhaps even host reduction. However, the right combination of these efforts will most certainly vary from one location to the next and be dependent upon available resources.
Perhaps the most effective way that every individual can reduce their risk of contracting any disease vectored by ticks is to practice several important personal precautions.