Spring burning and thinning pine stands can often breed harmful insect infestations, according to Bitterroot National Forest officials.
Agency foresters are warning private landowners that thinning pine stands or burning spring slash may inadvertently provide breeding grounds for insects, specifically, the pine engraver bark beetle.
Also known as the ips beetle, the pine engraver bark beetle searches for damp or moist wood to burrow, eat and ultimately breed large numbers.
Montana Department of Natural Resources and Conservation Community Forester Kurt Gelderman said the beetle often thrives in spring?s newly damp wood.
?The ips beetle has an eating and breeding life cycle,? Gelderman said. ?Right now, they are living under the bark in pine trees looking for more places to lay eggs. Although they generally come out in June, they normally look for damp slash piles to breed, until they emerge again in the summer.?
The summer, Gelderman said, is when the ips beetle burrow under a tree?s cambium layer, a layer of essential tree nutrients, to feed.
?They burrow down three inches beneath the bark, so you don?t see them,? he said. ?What ends up happening, is the beetle begins to lay egg chambers that eventually all join and feed together. The beetles nestle only in the top half of the tree, cutting off the necessary flow of tree water and nutrients. They end up stressing the top half of the pine tree, something that makes the tree more susceptible to the mountain pine beetle, to finish the tree off.?
Like the ips beetle, the mountain pine beetle also attacks and kills pine trees under the bark.
According to the Forest Service, mountain pine beetle epidemics contribute to widespread tree mortality that can alter a forest ecosystem.
?The problem is the ips beetle leaves trees more susceptible to the mountain pine beetle,? Gelderman said. ?That only adds to the infestation cycle.?
Gelderman said he?s received several phone calls from property owners, wondering why their pine trees are dying. More often than not, it?s the ips beetle.?
Bitterroot National Forest Forestry Program Manager Sue Macmeeken said although the ips beetle is not serious threat, they do cause future damage.
?What we generally see is the ips beetle either killing small trees or the tops of large trees,? Macmeeken said. ?There are three other bark beetles that often follow the ips, although they concentrate on the bottom-half of the tree. Ips beetles are not considered a serious problem, but because it?s been so dry in the valley for consecutive years, there are a number of dead trees that began with ips infestations.?
To avoid such infestation, forest officials recommend property owners leave piling and burning of slash to the fall months, allowing time for wood to dry. If property owners are currently thinning pine trees, officials recommend burning materials while thinning, instead of stock-piling wood waste. Waiting to stock pile firewood is also recommended.
For more information on pine engravers, bark beetles or questions regarding infestations, contact Gelderman at 375-0412 or Macmeeken at 363-7151.The Ravalli Republic
