County Warns of Red Fire Ants, Snails, and Use of Pesticides

Dr. Cheryl Wilen

By E.A. Barrera

After a season of rain that has brought green hills and almost every flower imaginable to San Diego County, people naturally want to walk and play in the restored scenery. The same rural countryside and neighborhoods that were burned by the Cedar Fire only 18 months ago are now awash in color and scent.

Although the blooming portion of nature’s life cycle is gorgeous for the folks who live here, it is also a smorgasbord for the insects and pests that suddenly have fresh food sources and new places to nest.

San Diego County’s Department of Agriculture is advising that a renewed infestation of Red Imported Fire Ants will be one of the results of so much rain. Fire ants can be especially dangerous

to family pets and small children. They nest in the ground and in the walls of homes and will attack animals and people that disturb their mounds.

“Fire ants typically attack when their nest is disturbed. When attacking, hundreds of fire ants swarm within a matter of seconds and inflict painful stings that feel like pokes from a hot needle,” said San Diego County Entomologist David Kellum during a news conference on March 14.

“Each sting itches and burns and leaves a blisterlike sore that could become infected if not treated carefully. Red Imported Fire Ants are especially dangerous to small children, the elderly, pets and wildlife. In fact, swarms of fire ants have been known to kill small animals and even people. Some people, maybe two out of 100,

are allergic to fire-ant venom, and if stung, can experience difficulty breathing and other life-threatening reactions.”

Swarms of red ants have been seen in common areas such as parks and golf courses. But they also can bury themselves in the gardens and lawns of private residences — and eventually, within the walls and pipes of homes. The county warned that if someone comes across a fire-ant nest or mound, they should call the California Department of Food and Agriculture at (800) 491-1899. The CDFA will send experts to check out the problem at no cost.

“When red fire ants move into an area, 40 percent of the other living creatures in that vicinity have been known to move out. That’s how dangerous these ants can be,” Kellum said.

He said the average ant colony numbers around 20,000, but in rainy years such as this one, a “super colony” could have a population of more than a million ants. Ants often nest in locations that provide them with protection against the heat and an abundant supply of water and food, he said.

“Potted plants are great for ant nests,” said Kellum. “They also like the base of trees and under cement walkways or decks.”

Although ants are annoying when they come indoors, Kellum noted that they can be beneficial outside by aerating soil, feeding on fleas, termites and other pests in the garden. But he warned that the best way to keep ants out of a home is to get them in their nests while they are still outside.

“While spraying chemicals inside the house may seem effective, it won’t prevent more ants from entering your home, which is essential for control, because most ants nest outside,” Kellum said.

Among tips for keeping ants out of the home, or exterminating them if they already have made themselves indoor guests, Kellum advises caulking cracks and crevices that provide entry inside the residence.

“Store attractive food in closed containers. Clean up grease and spills. Look for and remove indoor nesting sites, such as inside potted plants. Ant-proof kitchen garbage pails with sticky barriers such as petroleum jelly under the lip and pet dishes by placing them in a moat of water. Remove sweet food sources next to your house such as aphid-infested bushes and ripened fruit on trees,” Kellum said.

During the news conference, representatives of the San Diego Master Gardener Program and Supervisor Greg Cox offered tips on how to fight a number of pests invading a home without resorting to pesticides.

“Pesticides can cause serious damage to the environment,” Cox said. “Even if you can’t see the beaches and bays from your back yard, when you use pesticides, and it rains, those chemicals are washed into the storm drains and eventually into our bays.”

One nonpolluting approach advocated by county experts is a copper strip or plate wrapped around the base of trees and shrubs. Snails especially hate the feel of copper and will not cross a copper boundary. Another method for fighting pests without chemical pesticides is the use of beneficial insects and other organisms that kill pest insects.

“These are called natural enemies. In any pest management or plant care program, it is important to encourage these natural enemies by avoiding pesticides that kill them,” said Cheryl Wilen, the county’s integrated pest-management adviser. “You can also encourage beneficial insects by choosing plants that provide them with pollen, nectar and shelter and keeping ants out of pest-infested plants.”

Examples of so-called good bugs included syrphid flies and lady beetles, which consume aphids; lacewing larvae, which feed on many insect pests; parasitic mini-wasps, which lay their eggs in pests like aphids or caterpillars, so thus their hatching larvae consume the pest and kill it. Spiders also were described as a beneficial insect, because they like to feed on insects or other arthropods.

Wilen described how to handle pesticides in a home or garden.

“Always read pesticide product labels carefully and follow all directions on proper use, storage, and disposal of empty pesticide containers,” she said. “Product labels are your main source of information on how to use a product safely and legally. They include guidelines needed to protect you, your family and pets.”

She noted that several home remedies, such as mixing sugar with borax, could be useful, provided the mixture is correct.

“If you use too much borax, it will actually serve as a repellent and then the pests don’t swallow the mixture, and thus, they don’t die off,” Wilen said.

She said consumers should identify the pest problem within the home and choose the least toxic pesticide that targets pests.

“If you need help identifying the least toxic pest control method, contact your University of California Cooperative Extension office,” said Wilen. “Determine the right amount of pesticide to purchase. Purchasing exactly the amount you need for the application eliminates the need for storing unused pesticides. Try not to buy the supersized bottles of pesticide, as the natural instinct is to use more than you need. Use spot treatments whenever possible.”

Wilen advised that homeowners not over-water areas after applying pesticides.

“Never let pesticide runoff flow into storm drains. Do not apply pesticides outdoors when rain is forecast or when it is windy. Avoid applying pesticides on paved areas. Avoid applying pesticides in or near floor drains or sinks. Avoid applying pesticides on areas that will be washed or mopped with water, or where food is prepared or stored,” Wilen said.

The only allowable way to dispose of unused pesticides is through a household hazardous-waste collection site. For the site nearest you in San Diego County, call (877) 713-2784.

For more information on ants, snails and combating other pests as San Diego moves into spring and summer, call the County Department of Agriculture at (888) 846-0800 or visit their Web site at www.cleanwater.org and click on the “Healthy Garden — Healthy Home” icon. For additional information, call San Diego’s Master Gardener program at (858) 694-2849.