Aggressive, stinging colonies of wasps out early this year in Sacramento County

Yellow jacket infestations are hitting Sacramento County early this year, prompting specialists to eradicate the sometimes aggressive insects whose sting can kill.

The Sacramento-Yolo Mosquito & Vector Control District has received numerous calls from residents battling yellow jacket nests on their property. The yellow jacket population problem usually shows itself in late summer or fall.

“It’s definitely early to see yellow jackets now,” said Gary Goodman, district manager.

The district has recently received calls from Rancho Cordova and Folsom, but the biggest problem has come from Herald, a rural community in southeastern Sacramento County.

“We recently treated nearly 90 yellow jacket nests on a 5-acre property near the eucalyptus groves,” said Goodman. “When you consider that each nest can have hundreds to thousands of yellow jackets, this can quickly become a threat to residents.”

County residents may call the district if they need help in removing nests. If a colony is disturbed, the wasps can become persistent and pugnacious, increasing the risk of stings.

“Our field technicians can safely and effectively locate the underground nests and assist residents in removing them from their property,” said Goodman.

According to the University of California, yellow jackets usually sting at nesting sites, but yellow jackets will also sting if someone tries to swat them from a food source. The wasps are known for crawling into soda cans at picnics, then stinging the lips of a person who takes a sip.

A yellow jacket sting varies from person to person. Some only experience short-term, intense sensations, others substantial swelling and tenderness. Still others can die from an allergic response.

Defensive behavior gets more aggressive as populations become larger at the same time food gets scarce late in the season, according to UC’s Division of Agriculture and Natural Resources. In the fall, yellow jackets are mostly scavengers, ruining barbecues, entering garbage cans, frequenting dog food bowls and alighting on overripe fruit.

Yellow jackets can be controlled by covering garbage cans and using traps available at hardware stores.

Bill Lindelof: 916-321-1079, @Lindelofnews