Managing Mosquitoes in the Landscape
Nobody enjoys scratching mosquito bites and with the rate of mosquito-borne illnesses like West Nile Virus on the rise, managing mosquitoes in the landscape is more important than ever. But that doesn’t mean you have to douse your yard in chemicals. Mosquito management begins with limiting the habitat that attracts these pests to the landscape – primarily standing water.
Eliminate Standing Water
Mosquitoes require water for development. Adult females lay their eggs in slow moving or standing water. The first step to managing these pests is to eliminate standing water. Common places where water collects include trays beneath flower pots, watering cans, trash bins, old tires, and toys such as wagons or buckets. Cover garbage cans, store them upside-down, or drill a few holes in the bottom to prevent water from collecting. Remove collection trays beneath flowerpots and overturned or store toys and watering cans in a garage or shed. Recycle old tires and any other materials that may be holding water.
Puddles are another common breeding ground for mosquitoes. Look for areas where water collects in the landscape and work to reduce puddling. Fill low areas in lawns and walkways or enhance drainage to move water away from low spots. Also, pay attention to gutters and drains. Remove leaves and other debris regularly to keep water moving effectively. Eliminating these and other breeding areas provides long-term management of mosquitoes.
Manage Water Features and Bird Baths
Several landscape features are designed to hold water for decorative or functional purposes. Simple maintenance techniques will manage mosquitoes in these locations without interfering with use. Children’s pools, bird baths, and pet dishes are all potential sites for mosquito breeding. Change the water at least once each week to remove mosquito eggs and larvae.
Stocking ornamental ponds with fish that eat mosquito larvae is an easy way to provide long-lasting control. Fish in the genus Gambusia are aptly named mosquito fish, as they feed voraciously on the aquatic larvae. These fish are native and easy to care for, in fact, they basically take care of themselves.
In water features where fish are inappropriate, mosquito dunks containing the active ingredient Bacillus thuringiensisi, or Bt, provides safe and effective control. Bt is safe for fish and birds, so it can be used in birdbaths or in combination with mosquito-eating fish. Adding a fountain, filter, pump, or other device to circulate water creates an environment unsuitable for mosquitoes, which require still water to breed.
Keep Grass Trimmed and Tidy
Believe it or not lawn maintenance is an important component of mosquito management. Adult mosquitoes rest in tall grass and dense vegetation. Keeping grass cut back below five inches will encourage mosquitoes to look for more suitable cover. Also manage weeds in garden beds and trim low-handing branches and foliage from shrubs to reduce resting spots. Pay close attention to areas where activity is highest, such as around playsets and outdoor dining areas.
Excess moisture in the lawn can create pockets where mosquitoes are able to breed. Avoid overwatering, particularly on poorly-drained soils, and aerate soils as needed to promote adequate drainage. Keeping the grass cut low also works to reduce breeding sites in the lawn.
While eliminating all mosquitoes is not possible, following these practices will reduce populations in the landscape. You can further reduce exposure to mosquitoes by wearing long sleeved shirts and pants when outside during periods of high mosquito activity, mainly dusk and dawn. Finally, run an oscillating fan in areas where you enjoy sitting outdoors in the evening. Mosquitoes are tiny insects that avoid strong air currents.