BEND, Ore. -

It's an ominous sound: the buzz of yellow jackets in your backyard.

This year, more people are hearing that dreadful noise on the High Desert, thanks to the lack of rain.

"The spring was dryer than last year," Alpine Pest Management owner Glenn Bissell said Wednesday.

Roberts Field in Redmond reported observed rainfall totals nearly half the average. In July, it recorded no rainfall at all.

"All those conditions favor ground-nesting yellow jackets," said Bissell.

Many people don't even know an underground nest is there until they've disturbed it.

"We're getting a lot of cases where people are mowing their lawns and running over them with a lawn mower," said Bissell.

Yellow jackets chase whatever they think is threatening their nest.

We saw this first-hand after Bissell treated a nest at a home in northeast Bend. The yellow jackets thought our microphone was the perpetrator -- and attacked.

Our Facebook page was buzzing Wednesday, as a question we posted about this year's problem prompted more than 200 viewers to comment on the large number of yellow jackets in the area.

But it's not only humans they are bugging.

"Honey bees have a lot of honey stored at this time," said Ramesh Sagili, Ph.D., assistant horticulture professor at the Univeristy of Oregon. "A hive that is not very strong then they can take over those hives, they can just get in and steal honey from there and kill the young ones."

There are 12 species of yellow jackets in Central Oregon. The common yellow jacket and the Western yellow jacket are the most prominent in our area. Brissell says you could be allergic to one species, but none of the others.

With full nests, yellow jackets are more aggressive now than ever, as they search for food sources.

"You might have seen that they come to all of your picnic tables," said Sagili. "Because anything that is sweet and sugary, and also any kind of meat, they would be interested in that."

And a prediction of another mild winter could mean another buzzing season next year.

"The only thing that survives through the winter are the queens," said Bissell. "This nest could produce 50, 60, 70, 80 queens, and if we get that in all the nests we have around here, we'll have a much worse year next year than we have this year."

For information on how to bait yellow jackets or treat a nest yourself, you can visit Bissell's website at http://www.alpinepest.com/.

The Sunriver Nature Center has a nest, and the yellow jackets are feeding off one of their aspen trees. For more information on yellow jackets, you can visit the nature center.