by Bill Eck
In conversation with several residents of Forest Hills over the past few months, I have heard dozens of accounts of ticks being found on both people and their pets. Among these were several accounts of Lyme disease and other tick-borne diseases.
This subject is especially important to me since I have contracted Lyme disease thrice in my career, luckily getting treatment early enough in each instance to suffer no long-term negative health effects. My most recent infection resulted from a deer tick that I picked up on a wooded property on Linnean Avenue, south of Albemarle Street.
The obvious method for avoiding ticks and their associated disease is to avoid their habitat. This is impractical when your lawn and landscape are the habitat. Insect-repellant sprays and wearing light colored, long-sleeved shirts tucked into light colored pants which are in turn tucked into shoes or boots may provide some protection, but this can be impractical, especially in the heat of the DC summers when tick activity is greatest.
Another option is reducing the population of ticks on your property as much as possible through tick management programs.
The most frequently prescribed management technique is barrier treatments of insecticides sprayed at regular intervals on plants around the periphery of the landscape throughout the growing season (similar or identical to commercial mosquito control services). There are several issues with this however. The broad spectrum chemicals most commonly used in these treatments are toxic to honey bees and no matter how carefully they are applied to avoid actively flowering plants, there is still a high likelihood that a honey bee will land anywhere that a mosquito or tick might rest . These sprays do quite a number on beneficial predatory insect populations as well (i.e. ladybugs, green lacewings, praying mantis, trichogramma wasps, etc). This can cause outbreaks of problematic plant pests such as aphids, scales, lacebugs, mealybugs, and spider mites.
If there is a short-term/one-time event (i.e. the grandkids coming to visit for a week, or a dinner party in the back yard, etc.) then a “comfort spray” to the perimeter of the property might be appropriate to reduce populations of ticks and mosquitoes, but it should be done with a natural chemical that has low residual and persistence and is less likely to cause mortality of honey bees and beneficial predators for a long period of time.
Restricting the free access of deer onto the property with deer exclusion fencing may seem like the obvious option. Mice, other small mammals, and birds are also frequent hosts of ticks, so while deer exclusion may be one part of reduction of disease carrying tick populations on your property, this is probably not a very effective management technique overall.
Mice are the source of the Lyme disease (not deer); the white-footed mouse is the primary carrier/source of the Lyme disease bacterium. Because the larvae and nymphs of black legged ticks most commonly feed and mature on mice, supplying treated nesting material for the mice is a solution that may make sense if deer are excluded from your property. One way to do this is with “tick tubes”. These biodegradable cardboard tubes contain cotton balls that are treated with permethrin. This chemical is toxic to ticks but does not harm the mice or their young. When the mice make their nests with the treated cotton, they stay tick free which can greatly reduce the risk (ten-fold reduction) of exposure to disease carrying ticks by reducing the number of larvae that mature to the nymph or adult stages.
A New Option
Because adults and nymphs who cling to the foliage of plants waiting for a host to pass by have no easy access to water, they must return to the soil to rehydrate. Also, after a first feeding, larvae drop off their hosts, molt into nymphs, and overwinter in the leaf litter.
Because of these facts, a treatment to the soil can be effective at treating the nymphal and adult stages. The most effective treatment is with a granule containing permethrin in the spring and summer for control of host seeking nymph and adults, and again in the fall to control the overwintering nymphs.
This treatment can eliminate the need for tick tubes and barrier sprays and also has the added benefit of treating grubs (i.e. Japanese beetles, oriental beetles, and other turf pests), ants, mole crickets, and night feeding weevils (i.e. two banded Japanese weevil and black vine weevil; all of which are common pests in this area. The major issue is that it is highly toxic to fish and aquatic organisms and shouldn’t applied near streams or waterways.
Managing ticks often requires an integrated approach including landscape modifications such as pruning and removing weedy vegetation to reduce tick habitats as well as treatments. Treatments can be targeted to areas of the landscape specifically where ticks reside: in wooded areas and at property borders.
So What Should You Do?
Avoid tick habitats when practical. If you are spending time outdoors, avoid walking through tall grass and shrubby areas and avoid brushing against vegetation by staying in the middle of hiking trails. Use insect repellants and wear long pants tucked into your socks and light-colored clothing to make it easier to detect ticks. Check companions, pets and children frequently for ticks.
If you have a property that is in proximity to wooded areas, you should contact a properly licensed pesticide applicator (often your arborist or landscaper) to meet with you on your property to develop a tick management program specifically designed for your property to reduce infestations. This includes virtually everyone in Forest Hills, especially those within a few blocks of Rock Creek Park, Melvin C. Hazen Park, or Soapstone Valley Park. Ticks are somewhat active during warm periods in the dormant season, but activity can be expected to increase significantly with the warmth of spring. The best time to begin tick management on your property is yesterday; the second best time is tomorrow.
Worry less and enjoy your landscape more!