In the Landscape
Ticks like dark, humid places—leaf litter, low bushes, tall grasses. Ticks do not thrive in sunny, mown areas.
- Remove leaf litter. Keep brush cleared.
- Remove invasive bushes such as barberry and honeysuckle, which create safe havens for small rodents carrying ticks, protecting them from predators.
- Keep grass mowed closely.
- Create a 3-foot-wide buffer of landscaping material such as stone or woodchips to separate lawn from tick-friendly areas.
- Move children's play areas away from woods.
- Keep bird feeders away from highly traveled areas of yard (birds and rodents such as red squirrels and mice carry ticks).
- Use the wide variety of deer repellent devices and compounds available on-line or in gardening and hardware stores. Use deer-resistant plants.
- If possible, install a deer fence around your property.
Outdoor sprays and granules can be applied to individual properties from May through September.
Natural sprays (recommended)
The field of non-synthetic botanical insecticides is growing rapidly, and products containing oils from plants such as rosemary, peppermint, cedar, and eucalyptus are available. Preliminary research indicates that they are effective, though more scientific documentation is needed. Must be applied by a licensed applicator; two applications required. May be more expensive than synthetic sprays.
Synthetic sprays (not recommended)
Contain chemicals such as permethrin and bifenthrin, known as synthetic pyrethoids. They are effective in killing ticks. However, users should be aware that most of these products have labels warning that they are toxic to fish, shellfish, and bees. There is growing concern that these substances may be a cause of bee colony collapse and have unintended harmful effects upon other organisms. For this reason they have been banned in Europe and in many U.S. communities. The decision as to whether to use products containing these chemicals is up to the individual property owner.
Most synthetic sprays require two applications. Some must be applied by a licensed applicator; several mid-coast companies are listed under Pest Control Services. The cost is $200-$300 for a 4–5 acre property. Other sprays may be applied by individual property owners and require special equipment. The cost is about $100 per application for about 4–5 acres.
Contain synthetic pyrethroids. Apply with a spreader, last about 4 weeks. About $24 for 10 lbs., which covers 5,000 square feet.
Small rodents such as white footed mice, chipmunks, red squirrels, voles, and shrews carry the bacteria that cause tick-borne disease, and infect the ticks when ticks feed on them.
- Products like tick tubes and bait boxes to control ticks on rodents are effective in small areas if strategically placed (along walls, near wood piles).
- However, they must be consistently replenished, for rodents are enthusiastic reproducers. In the March-November breeding season, a mouse can have several litters, with an average of 4–7 mice per litter.
About Damminix tubes...
- Cardboard tubes are filled with permethrin-treated cotton balls that mice collect to build their nests. Available at garden centers. $29.99 for 6 tubes.
- Tubes should be placed no more than 30 feet apart. An average 1-acre yard requires about 24 tubes per application.
- Ticks feeding on nesting mice in the spring and fall are exposed to the permethrin and die.
- Tick tubes are not effective for red squirrels, voles, and shrews, which do not build their nests as mice do.
- Birds that eat mice that have been exposed to permethrin are not harmed.
- You can make tick tubes yourself with toilet paper tubes and cotton, and if you do, you should wear rubber gloves and a mask. Be sure that there are no cats in the area, for when it is wet, permethrin is highly toxic to them.
- Note: Some field studies have shown that tick tubes may not kill a sufficient number of ticks to prevent tick-borne disease. Alternative hosts like red squirrels, voles, and shrews can sustain a tick population by themselves.
About "Bait boxes”...
- These contain a wick soaked in fipronil, a synthetic pesticide that kills ticks on mice (the mice are unharmed), and are available through licensed applicators.
- Put out in May, replace in August. A single dose will protect mice for 40 days.
- Each box costs $50; 3–4 per acre.
- The Connecticut Agricultural Experiment Station is currently studying the effectiveness of bait boxes.
- Scientists believe that a pathogenic fungus called Metarhizium anisopliae may be effective in killing ticks, and a granular insecticide containing the fungus called Novozymes MET 52 is commercially available. However, more scientific analysis is needed.
- Nootkatone, a tick-killing botanical derived from Alaskan cedar, has done well in studies funded by the Centers for Disease Control. However, the cost of the cedar is high and the supply is limited.
The following measures have been found to be ineffective for tick control:
- Guinea hens. Scientific studies have shown that guinea hens may feed more ticks than they eat.
- Burning fields. While ticks are suppressed after a field is burned, scientific analysis has shown that they soon return. Furthermore, extensive field burning would cause a fire hazard on Islesboro.
- 4-Poster Deer Treatment System. Maintaining enough four posters to effectively control ticks may be prohibitively expensive and labor-intensive.