In these frigid spells, people are often heard saying, “Well, at least it is killing off some of the bugs.” Is there anything to that? I know the Far North is noted for mosquitoes and black flies. Do the voles ever get too cold?
1 Like
I’m sure these temps are messing with plenty of critters. I did see something the other day that emerald ash borer larvae are impacted significantly at temps below -25. I’d think that would mean the western spread of EAB would be slowed some this year.
Yes, my anectdotal experience is “yes” to more bug mortality in a cold winter.
But, I’m not a scientist…so
Big time for insects that surface or shallow overwinter. Really hard on yellow jackets and other wasps.
Bugs that bury themselves deep like cuke beetles and Jap beetles, won’t suffer too much.
Iowa state etymologist said that many of EAB larva will die but the survivors will breed back.
1 Like
I wonder how plum curculios and codling moths do?
Some one smarter than me will answer that, sry.
Plum curculio and codling moth are both very active in Minnesota so they must be pretty cold tolerant. I expect that there will be many fewer in a spring after a harsh winter, but they will breed back to strength in short order.
There are places in Canada which don’t have codling moth. Codling moth larvae supposedly can’t survive below about -24. I remember reading once from a guy in Canada whose winter temps regularly hit that saying, “we should be thankful”.
SWD is one which can’t take super low winter temps. The problem with that one, as Scott alludes can be a problem, is the breeding/life cycles are rapid. It can be reintroduced every summer, and populations can build so fast, it seems they never died.
1 Like
The best thing, that I’ve been told, is when there is a good long warm spell followed by a deep freeze. The idea is that some insects will emerge, and some eggs will hatch, and then freeze before they can complete their life cycle. Predatory insects most likely emerge/hatch later so will be less affected. Probably not so good for fruit trees but great for vegetable farmers.
Fruit flies might be able to survive all winter in buildings, they can also be brought great distances from warmer areas in weather systems as “aerial plankton”, and of course fruit shipped up from the south.
Went searching to confirm about warm spells and found this, keep in mind it is mostly about corn and soybean pests
What conditions are likely to cause the greatest decrease in an insect population in Kentucky?
- It appears that cold, wet weather, particularly with wet but not frozen soils for insect overwintering in the ground, and lack of snow or ice cover will cause the greatest or at least the most common decrease in survival of overwintering insects in Kentucky,
- Extreme cold that is not moderated by snow or ice cover increases mortality but is a rather rare event.
- Repeated wide swings in temperature, alternating warm and cold during the traditionally cold months (e.g. Dec – Mar).
- A long, warm period late in the traditionally cold season followed by a quick return to very cold conditions.
- Consistently cold but "average temperatures are not as damaging as most people expect.
https://www.agprofessional.com/article/winter-weather-effects-insect-populations
2 Likes
Well, there is hope, then. We were very cold last night.
My wife was just telling me about EAB and temps… we had -31F here and most areas anywhere within 2 hours of here seem to have been -25F or colder…so i would think a significant reduction in the local area. The bug i’d love to see die off is the spotted wing drosphilia.
1 Like
Maybe some, but not nearly as much as we like to think. I bring in firewood, and the next thing I know there’s a mosquito trying to bite me…little critters are truly amazing, and have millenia to evolve to survive the climate their species chose.
1 Like
Heard a mosquito today.
And a friend says he has a limb on an apple in bloom in Middlesboro, KY. It’s in 60’s,
(3 degrees less than a week ago one night).
Here in Alaska the kind of winter can have a huge impact on insect pressure. For instance mild winters can bring hordes of yellow jackets.
Every year is anybody’s guess what’s going to be around. One year it was aphids, they were everywhere. I have not seen them around like that ever since but I’m sure I’ll see them again. Another year it was sawfly larvae, a veritable infestation that ate an entire jostaberry bush in record time. This year? Leaf rollers. They usually can’t muster enough numbers to do much damage to a tree but they are certainly trying.