* When outdoors, wear long pants, long sleeve shirt and other protective clothing.
* Apply effective insect repellent according to instructions.
* Vaccinate your horses.
* Eliminate standing water.
* Properly dispose of all unwanted containers that catch and hold rainwater, cans, plastic containers, buckets, and ceramic pots.
* Punch holes in the bottom of tires used for play or landscape to drain water.
* Clean & chlorinate swimming pools; empty unused ones. Remove water from swimming pool covers.
* Fix dripping faucets and eliminate puddles around faucets, downspouts, and air conditioning systems.
* Check hole(s) in trees for water. Consult tree specialist to see if hole may be safely filled with sand or mortar. Place mosquito dunk (larvicide) in hole.
* Eliminate standing water in potted plant containers and saucers.
* Change water in birdbaths, pet water bowls, fountains, and watering troughs frequently – at least twice a week.
* Turn over unused wading pools.
* Ensure that trash cans and recycling containers left outdoors have drainage holes on the bottom.
Do not leave garbage can lids upside down.
* Turn over wheelbarrows and canoes.
* Cover containers tightly when storing rainwater for garden use.
* Clean leaves and other debris out of rain gutters: clogged gutters are prime mosquito habitat.
The Union Democrat
Monday, June 9, 2008
Farm Adviser, Scott Oneto
This article adapted from the University of California Integrated Pest Management Program and the Centers for Disease Control and Prevention. Contact Scott Oneto at the Tuolumne County Farm Advisor's Office, 52 N. Washington St., Sonora, at
sroneto@usdavis.edu or by calling 209/533-5686.
There are more than 50 species of mosquitoes in California. They occur in a variety of habitats in the state, ranging from deserts at or below sea level to high-mountain meadows at elevations of 10,000 feet or more. Many species of California mosquitoes are relatively uncommon and seldom pose a threat to the health or well-being of California citizens. However, there are several species that readily attack people, and some are capable of transmitting microbial organisms that cause human diseases such as malaria and West Nile Virus.
With the arrival of warm weather comes the breeding of mosquitoes and the threat of getting bit. Mosquito adults are small, flying, midge-like insects. Female mosquitoes can be differentiated from similar insects by the presence of a long slender proboscis that is adapted for piercing skin and sucking blood, and long slender wings. Male mosquitoes have a shorter and thicker proboscis that is adapted for sucking plant juices and other sources of sugar rather than blood.
The life cycles of mosquitoes vary widely from species to species. Some female mosquitoes lay single eggs on water surfaces; others lay single eggs on moist soil where later flooding is likely. Still other species lay batches of eggs, 100 or more at a time, on water surfaces. Eggs deposited on water surfaces usually hatch within a day or so. Larvae, which are nearly invisible to the naked eye, hatch from eggs.Over the next couple of days, the larvae molt, eventually becoming pupae one to two days later with the entire cycle completed in a week or less.
Female mosquitoes of nearly all species require blood from vertebrate animals to develop eggs, and many species bite people, pets and livestock for this purpose. The most important consequence of this is the transmission of microorganisms that cause diseases such as West Nile virus. West Nile virus is a serious disease of humans and other animals that can be fatal. Mosquitoes become infected when they feed on infected birds. This year, 100 dead birds from 18 California counties have tested positive for WNV, compared to the 25 dead birds in nine counties in all of 2007. Mosquitoes also vector dog heartworm in California. Oak trees, which are common throughout this area, provide natural crevices that fill with water and harbor the larval stages of the principal vector of this disease.
The most effective ways for individuals to prevent exposure to mosquito bites are:
DEET - Apply insect repellent containing DEET, picaradin, oil of lemon eucalyptus or IR3535 according to label instructions. Repellents keep the mosquitoes from biting you. DEET can be used safely on infants and children 2 months of age and older.
Dress - Wear clothing that reduces the risk of skin exposure.
Dawn and dusk - Mosquitoes that carry West Nile virus bite in the early morning and evening, so it is important to wear repellent at this time. Make sure that your doors and windows have tight-fitting screens to keep out mosquitoes. Repair or replace screens with tears or holes.
Drain - Mosquitoes lay their eggs on standing water. Eliminate all sources of standing water on your property, including flower pots, old car tires and rain gutters. For pet water bowls and bird baths, keep the water fresh by changing it regularly. If you have a pond or livestock water trough, use mosquito fish or treat the water with the microbial insecticide Bacillus thuringiensis subsp.. israelensis that kills the larvae. This material is biological in origin and is highly specific for mosquitoes, with little or no effect on other organisms.
Keep in mind, however, that mosquitoes can migrate several miles from where they develop. Even successful control of mosquito larvae on your premises may not result in reducing mosquito numbers or biting activity. So it is important that everyone take a proactive approach in controlling mosquitoes around their homes.
For more information about mosquito control and or other pests, contact the Farm Advisor's office at
sroneto@ucdavis.edu or 209/533-5686.
