Pesky problem should disappear

Written by Kelly Ducote, The Observer November 15, 2013 09:50 am

Hayley Crews suddenly finds her jogging slightly inhibited as she tries to make her way through a cloud of swirling aphids on a balmy, sunny afternoon earlier this week in La Grande. (CHRIS BAXTER/The Observer)
Hayley Crews suddenly finds her jogging slightly inhibited as she tries to make her way through a cloud of swirling aphids on a balmy, sunny afternoon earlier this week in La Grande. (CHRIS BAXTER/The Observer)
 

Upcoming cold weather should rid area of aphids

The annual rein of a nuisance insect should soon be ending for the area.

Aphids, which are commonly seen during fall, should be seeking winter shelter and disappear this weekend.

Paul Oester of the Oregon State University Extension Service said it’s not uncommon to see swarms of the insects around this time of the year.

“They’re migrating. They’re trying to find overwintering locations,” Oester said.

Though the aphids make an annual appearance, Oester said they seemed to be pretty bad this year.

“About a week ago you could almost breathe them in there were so many of them,” he said. “There could be a number of factors of why we’ve seen so many.”

It could mean they were successful this year in population development. Warm spells during fall could have also kept more alive. That could mean more aphids in 2014.

“It depends on how they overwinter. It depends on predator parasites,” Oester said, adding that diseases and cold temperatures could also affect aphid populations.

Aphids are generally considered a nuisance as they rarely cause problems. They do not bite and usually do not harm trees or other plants.

“The aphids were really bad this year,” said La Grande Tree Care Educator Teresa Gustafson. “I had a lot of calls from people this summer concerned about aphids on their trees.”

Gustafson said the aphids suck sap out of leaves and excrete honeydew, but “as a rule they don’t harm the tree.”

However, ash trees in the area were hit hard, Gustafson said.

“[Aphids] can usually be controlled with non-chemical treatment,” she said. “A systemic insecticide can be used for severe infestations.”

The good news for annoyed residents is that freezing temperatures should send the insects to their winter homes. With snow forecast for this weekend, that means they will likely disappear for the year.

“They will stop flying around after a few frosts,” Gustafson said.

Contact Kelly Ducote at 541-786-4230 or This e-mail address is being protected from spam bots, you need JavaScript enabled to view it Follow Kelly on Twitter @lgoDucote.