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Bobble heads of the insect world – Audio

PJ Liesch, UW-Extension entomologist
Department of Entomology
UW-Madison College of Agricultural and Life Science
Twitter: @WIBugGuy

3:00 – Total time

0:13 – What are the insect bobble heads
0:42 – What do they do
1:21 – What to do about the insects
1:55 – Other insects in firewood
2:32 – How to store firewood
2:50 – Lead out


Side view of a wood wasp showing the scrawny “neck” and “bobblehead” appearance. Photo: PJ Liesch

Lorre Kolb: Bobble heads of the insect world. We’re visiting today 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 Lorre Kolb. PJ, what are bobble heads of the insect world?

PJ Liesch: So there’s a really interesting creature. It’s technically called a wood wasp from the Family Xiphydriidae, but they’re these wasp-like creatures about an inch long and if you see them they really look like bobble heads. They’ve got essentially a skinny neck-like region and this large bulbous head. And the story behind these is that they live in dead, dying, rotting trees and they end up showing up in people’s homes this time of year, specifically because of firewood.

Lorre Kolb: So what do they do, how do they affect people?

PJ Liesch: Well they’re really pretty harmless. A little bit of a nuisance, but again, the story with these is they get brought in on firewood because the fallen over, rotting tree in the woods gets chopped up into firewood. People bring the wood material indoors and it’s typically a case where the wood sits there. You’ve got a wood-burning fireplace, you have ambitions to have fires all the time and you don’t really, so the wood sits indoors, it’s nice and warm. The insects are developing in the wood as larvae, they think it’s springtime so they pop out. And it’s often about February and into March we get lots of reports of these bobble head-like insects and a number of other things that can pop out of firewood.

Lorre Kolb: So what should people do if they find these bobble heads in their houses?

PJ Liesch: Well if you have these insects or really any others that you suspect might be coming from firewood, they’re going to be harmless to people. You can catch them in a small Tupperware, suck them up with a vacuum cleaner hose attachment those sorts of things. The biggest solution though is take the firewood, move it back to a colder location, either back outdoors or into an unheated or semi-heated garage. But we want to get them to a cooler location – that’s going to slow down or stop the insect’s development and activity any further.

Lorre Kolb: Can you give us examples of other insects that might appear in firewood?

PJ Liesch: So there are a number of beetles that can emerge from firewood. There’s one group we call the long-horned beetles or the round-headed borers and there are a solid handful or more of species that I will commonly see again a very similar story where they show up indoors in January, February, March – times of the year where it’s cold enough you’re not expecting insect activity and all of a sudden you have them flying around or crawling around your window. Occasionally certain ants, like carpenter ants, can be brought in in firewood. And if that’s the only source of the ants, again, it’s not a concern we just have to move the firewood out to colder locations.

Lorre Kolb: What are some things people should think about when they’re gathering their firewood?

PJ Liesch: When I think of a situation where you have firewood around either for a fireplace or especially if you’re relying on the fireplace to heat your home or a cabin would be to keep the firewood as cold as possible, but also use it up relatively quickly.

Lorre Kolb: We’ve been visiting today with P.J. Liesch, Department of Entomology, Insect Diagnostic Lab, University of Wisconsin-Madison/Extension, and the College of Agricultural and Life Sciences and I’m Lorre Kolb.