Monday’s swoosh of cold wind was the best trick to rid the area of those pesky, tiny insects making their way into the eyes, mouths, and noses of unsuspecting victims.

“They gross me out,” said UI freshman Kasey Heuton as she sat outside Schaeffer Hall, a popular hangout for the bugs. “One smashed against my sweatshirt and left a stain.”

Clusters of little green insects, formally known as winged soybean aphids, are swarming the UI campus. But as colder weather approaches, the aphids will soon leave for the woods.

Aphids have an unusual lifestyle, causing them to switch landscapes twice a year, said Donald Lewis, an extension entomologist at Iowa State University.

In late spring and early June, aphids migrate to soybean fields from wooded areas, often tormenting soybean farmers. When soybean plants ripen in the fall, aphids vacate the fields and return to the trees.

A change in the weather has affected this yearly process — the reason ISU entomologists believe so many aphids are harassing the UI campus this fall.

August was abnormally dry this year, causing soybean plants to ripen at the same time. Once the plants ripened, aphids left the fields simultaneously to ravage trees.

“It is the return movement of billions — could be trillions — of aphids that people have noticed, as clouds or swarms of aphids pass above lawns, sidewalk trails, bike paths, and the landscape in general,” Lewis said.

As cooler weather arrives, aphids will retreat to woodlands, then mate and lay eggs on buckthorn trees, where they will remain dormant until spring’s arrival.

“Though we may see winged aphids flying around until the end of October, the worst is probably over,” Lewis said.

But luckily the irritating creatures aren’t dangerous.

“They can’t bite, they don’t carry diseases to people, and they can’t sting,” Lewis said.

Combating trillions of these insects is impossible, experts said, but one method can help control the infestation.

Charles Mason, an exterminator with Alias the Bugman, 1440 Pine St., tries a green approach for his pest problems.

A simple solution — water diluted with dish soap — can help kill off some of the aphids making trees around campus their homes.

Mason said soapy water clogs their pores and eventually kills them. However, it won’t stop the next generation of aphids that will arrive several days later.

“The greener you can go, the better it is,” Mason said.

Even with attempts to flush the insects, the only real solution will arrive with the first frost.