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Firewood, Christmas trees, and hitch hiking bugs – Audio

Firewood, Christmas trees, and hitch hiking bugs - Audio
Insects can get into the house on firewood
Insects can get into the house on firewood

P.J. Liecsh, Extension entomologist, Insect Diagnostic Lab
Department of Entomology
UW-Madison College of Agricultural and Life Sciences
(608) 262-6510
Total Time –2:56
Firewood hitch hikers– 0:19
Types of Insects –1:01
Potential risks to humans– 1:29
Christmas tree hitch hikers—1:57
Getting rid of them– 2:35
Lead Out– 2:45


Sevie Kenyon: Watching out for hitch hiking insects on firewood and Christmas trees, we’re visiting today with P.J. Liesch, Insect diagnostic lab, Department of Entomology University of Wisconsin – Madison/Extension in the College of Agricultural and Life Sciences and I’m Sevie Kenyon.  P.J., uninvited guests for thanksgiving on that firewood?

P.J. Liesch: So it turns out, there’s a pretty wide range on insects that can be brought indoors without us knowing in materials such as firewood and it turns out a lot of those insects can be common out in nature and people cut down trees, bring in firewood, the insects are already in there and the problem we run into is if that fire wood is brought indoors and it’s left to sit for significant amount of time, weeks or months, and the insects that were in the wood think it’s spring time because it is warm enough so they complete their development and all of the sudden out pop all sorts of weird beetles or wood wasps or other creatures.

Sevie Kenyon: P.J.  maybe we can go back to that menu of insects what could they be?

P.J. Liesch: So there’s a very wide range of beetles: long horn beetles and flat headed beetles and several other beetle families that these insects specifically go after stressed or dying trees out in the woods. They often live beneath the bark or maybe tunneling through the wood, there are some creatures called wood wasps that do very similar things and a number of other creatures that all have that same kind of behavior.

Sevie Kenyon: Are there any potential threats or dangers to the humans of the household?

P.J. Liesch: For the most part, no. The creatures that will pop out of firewood, for example, it’s really a dead end for them if you think about it because they are not going to be able to find a mate most likely or suitable habitat a dying tree to infest. And so, for the most part they’re just a nuisance, but they’re not going to harm furniture or the framing in the home. You just have some extra creepy crawlies to deal with for a while.

Sevie Kenyon: And, do hitch hiking insects come in on Christmas trees as well?

P.J. Liesch: They can, yes. Each year in December and January, I get a number of reports in the state of various creatures coming in on Christmas trees. Probably the most common would be a type of aphid, and this species of aphid will lay eggs on the Christmas tree branches. Well, those trees are brought in, warms up, and so the eggs hatch and we get these dark colored aphids on the twigs and it can be a little alarming, because those aphids can look a little bit like ticks in some cases if you’re not expecting them. They’re mostly just a nuisance in the house.

Sevie Kenyon: P.J., you bring in some of these insects how do you get rid of them?

P.J. Liesch: Probably the best way for these late season insects is to haul out the vacuum cleaner with the hose attachment and suck them up. There’s no need to haul out insecticides and spray for them.

Sevie Kenyon: We’ve been visiting with P.J. Liesch, Department of Entomology, Insect diagnostic lab, University of Wisconsin – Madison/Extension in the College of Agricultural and Life Sciences and I’m Sevie Kenyon.