By JORDAN STRICKLER

Kentucky Correspondent

LEXINGTON, Ky. — Frigid weather has created havoc across the country, including winterkill of wheat across the Midwest, and that has some wondering whether farmers will see a benefit in reduced pests in the spring.

The answer is, it depends.

“I think it’s too early to say whether there will be any benefits from this cold regarding pests, at this point,” said Ric Bessin, extension professor in the Department of Entomology at the University of Kentucky College of Agriculture, Food and Environment. “What happens to an individual species in one area may not be affected to the same degree as a species in another area.”

Cold snaps that have lasted weeks and caused temperatures to drop to the negative double-digits will probably result in some improvement with regard to specific pests. This is especially true in areas that didn’t receive as much snowfall, as that can act as an insulator to the cold.

“Without snow cover, the effects of the cold are more severe on insects in the ground,” Bessin explained. “Since snow insulates the ground, generally under the snow, it may be very close to freezing, even though we may have air temperatures that are 20 or 30 degrees colder.”

He said there are some insects that are highly affected by cold temperatures, which could benefit producers. Pests such as the armyworm are mostly eliminated after the first freeze. Insects such as sugarcane aphids, while not directly affected by cold temperatures, are affected circuitously.

“These insects need to pass the winter on a live host, which is Johnsongrass (in Kentucky). So while the winter may not kill the insect, it will kill the host, which then kills the insect. Those would be pushed far enough south, where Johnsongrass can survive the winter.”

On the other end of the spectrum, there are some invaders that will not be affected by the recent cold and whose populations will remain relatively stable.

“Some insects have developed elaborate strategies to survive winter. Some of them, like stink bugs, lady beetles and different types of flies, go inside our homes and are absolutely protected by the weather,” Bessin noted.

“Some others have the ability to produce agents that keep their blood from freezing. Things like the European corn borer can survive extremely low temperatures.”

“Some crops, fruit trees and even livestock animals may fall prey to cold weather, but insects can survive even record cold,” said Dr. Xing Ping Hu, an extension specialist professor of entomology and plant pathology at Auburn University. “Insects have been around for ages and have survived a wide range of weather conditions.

“They have developed strategies for surviving even in the coldest temperatures by entering diapause – ceasing to feed, grow or reproduce – by hibernating in protected sites, by burrowing deep down into protective sites, such as leaf litter or the ground, or by sneaking into human-built structures.”

The mosquito is one example of an insect that always makes a comeback despite temperature. Alaska and Minnesota are prime examples of the adaptive nature of this universal pest; these states, known for brutal winters, also have ruthless mosquito populations in the summer.

“In fact, mosquitoes are far more susceptible to the lack of spring rainfall than they are to prolonged and unusually cold weather,” said Hu.

Bessin explained while the cold can be good in getting rid of some pest insects, it can be detrimental to beneficial ones, such as bees. “One of the things that concerns me about the cold we’ve seen this year is the prolonged nature of it.

“The late December or early January temperatures lasted for several weeks, and that can be particularly tough on bees because they sit in a cluster and they eat all of the food in the cluster. The cold weather makes it difficult for them to move even the shortest of distances.

“The colony might have lots of food, but they might not be able to get to it when it’s that cold for that long,” he added.