This morning I turned on the weather at the local Fox affiliate. The weatherman was reminding all that we are going to see -20 to -30 below air temps with wind chills in the 50-60 below. He stated that the one positive is that the Emerald Ash Borer is killed at those very cold temperatures! I never heard that, can anyone confirm that.
a quick search found this https://www.google.com/url?sa=t&rct...SIsEdECKQwOW8Pf6A&sig2=mpUJSm-RUC5txJ6yk05aug
Not much hope for us in Kentucky. Our winters seldom reach temps cold enough to do any serious damage to their population. In my area I've not seen a live or undamaged ash in years. To treat one or two ash trees in your yard can become financially embarrassing! You can't treat the tree just once, they have to be treated annually and it ain't cheap. Some guys around here are getting $250 a tree every time the inject one. The bad part is homehoners will notice damage the call someone to treat the tree. It's too late by then because it will die no matter what. Treating a damaged tree may slow it's death but it won't save it, something most "tree guys" around here forget to tell you until after they cash your check.
Oh yeah, kill them sob's. I know another university did a similar study, iirc it was Michigan state university, and they deduced the same thing as that university of Minnesota study. Where EAB comes from in Asia, it does not get as cold as it does here. Two winters ago did a number on the EAB here. Last winter. Not so much, but this winter should put a good hurt on them again.
I think I read somewhere that extreme cold does a gooder number on ticks as well, but I don't remember what that temp is.
I've heard that as well. I wonder if it's more a case of cold weather killing their host animal, or just a pure function of temperature?
I dont know if it kills ticks or not. Even tho i live here in indiana, used to go hunting every year up in northern wisconsin, deer ticks were terrible up there, and it gets pretty cold there.
I remember seeing a video of deer ticks being frozen in ice and then when they are thawed out they come back to life.
whitey I too wondered this and it appears that one or two nights of that temperature might kill a few but not that many. It seems to take a long while to be certain. For example, in the USFS article (first link), we find this: "Naturally infested logs were held outdoors in St. Paul, MN (low winter air temp = -28°C) and near Grand Rapids, MN (-34°C) for ca. 5.5 weeks. Approximately 40% of larvae from logs in St. Paul were inactive or brown, both evidence of death; approximately 90% of larvae from logs near Grand Rapids were inactive or brown, compared with the approximately 10% that showed evidence of death prior to exposure or after being held under cool, non-lethal conditions." So, one has to wonder if the temperature reached -20, say 3 nights in a row but warmed to perhaps zero or a bit above, then the mortality rate would not be that high. In addition, most areas that reach -20 might do so for only one or two nights before warming up a bit. Therefore, only in the extreme north where it might stay that low for an extended time would the cold have that much effect on them. For us and for many others, it is too late...
The continuing education classes that I have to attend once a year to keep my commercial applicators licence are put on by Iowa state university. Their research has shown that cold has little to no effect on EAB living in standing trees. As air temps change, so does the temp under the bark of the tree. Sun shine warming the bark of the tree also has an effect on the temp under the bark where the larvae live.
Conflicting? Not really. I didnt read any where in the U of M's study that said cold had a 100% kill on EAB. I'm sorry I cant offer up a lnk tp ISU's paper work, I just know what the top 3 egg heads from ISU told myself and others in several different classes and seminars on the subject.