The emergence of West Nile Virus has focused public attention on mosquitoes. Fear may cause you to reach for a pesticide spray can, but control this way can be spotty at best, and not get to the heart of the problem – their breeding place. In fact, most of your bites may be coming from mosquitoes you are raising in your own backyard!

The young mosquitoes (larvae) live in water and fed on organic matter and microorganisms. Just about any area or container that can hold water for more than a few days can produce a large crop of mosquitoes. The most effective way to control mosquitoes is to find and eliminate their breeding sites.

Eliminate standing water in containers around your home, including water in cans, plastic containers, potted plant saucers, buckets, garbage cans, barrels, wheelbarrows, and any other container that can hold water for more than a few days. Empty the water, and then either turn them over, punch drainage holes in them or dispose of them.

Change water in birdbaths and pet water dishes at least once a week, preferably every 2-3 days. Fix leaky outdoor faucets and sprinklers, and don’t over water your yard. Any standing water can produce mosquitoes. Recycle tires or store them so the don’t collect water. Take down tires swings for the winter so they can’t collect water during the rainy season. They are extremely hard to drain and each one can produce thousands of mosquitoes.

Keep roof gutters clean so water drains, otherwise mosquitoes can breed in the water and leaf mixture. The decaying matter also provides food for the dense numbers of mosquito larvae. Drain plastic wading pools or fountains when not in use, or cover tightly to deny access to mosquitoes. If the fountain is large enough, stock with mosquito fish or add Mosquito Dunks containing BT (Bacillus thuringiensis) to the water as needed. The natural bacterium is a stomach poison to mosquito larvae and black fly larvae only. Other aquatic life is unaffected by the product.

You can obtain mosquito fish (Gambusia affinis) at no cost through your county mosquito abatement and vector control district. They can also be used in ponds, container water gardens, and watering troughs. These fish do not require supplemental food. In fact if overfed, they may not feed on mosquitoes and excess food may cause bacteria blooms that harm the fish. Make sure and treat the tap water with Chloramine Buster because water containing chloramine is toxic to mosquito fish and must be chemically treated first.

Another source for mosquitoes can be tree holes. The western tree hole mosquito is the primary vector for canine heartworm in our area. Fill tree holes with as polymer such as Soil Moist or Broadleaf P4. In the winter, the granules absorb the water and eliminate mosquito breeding habitat. The granules can last for many years, absorbing water in winter and drying out in summer.

Written by:
Matt Lepow, Owner, CCNPro, B.S. Ornamental Horticulture