Public urged to prevent mosquito-breeding sites

Above-average rains in March could lead to more backyard pests as spring begins.

“As we head into spring, we’ll see more pests emerging from their winter habitats to feed on the increased plant growth caused by the rain,” said County Entomologist David Kellum.

Common backyard pests in our region include snails, Argentine ants, honeybees, aphids and caterpillars. If you find a critter you can’t identify, submit it to the Department of Agriculture, Weights and Measures so they can figure out if it is harmful to plants or humans.

Agriculture officials often depend on the public to help them find out about new plant-damaging pests and to monitor the spread of those already in the area, which can sometimes lead to quarantines. Current quarantines include: the diaprepes root weevil in the North County, the Mediterranean fruit fly in El Cajon, and the Asian citrus psyllid in areas of the county south of Highway 78.

The County is also working with several other agencies to manage a new pest called the gold-spotted oak borer. It is suspected of damaging or destroying thousands of oak trees in the eastern part of the county.

Other pests may be harmful to humans, such as mosquitoes which can spread West Nile virus. A record-number of human cases was reported in the county last year.

“There’s no way to predict what it will be like this year, but people can help prevent the disease by getting rid of standing water around the yard. Rainwater may still be sitting in the bottom of pots, children’s toys, birdbaths and even old tires. These are perfect breeding sites for mosquitoes,” said Chris Conlan, Vector Ecologist with the Department of Environmental Health.

You can also protect yourself by: wearing long pants and long-sleeved shirts when you are outdoors; using repellent containing DEET, Picaridin, Oil of Lemon Eucalyptus or IR3535 on clothes and skin; and making sure screens on windows and doors do not have holes.

Learn more about pests by watching the slide show on the County’s Web site at

To find out more about West Nile virus prevention, visit