by Dawn Ballou, Pinedale Online!
August 30, 2009
Liz Davy, Bridger-Teton National Forest Timber & Silviculture Program Manager, gave a talk about Pine Bark Beetles on Thursday, August 27th at the Sublette County Library in Pinedale.
She said she estimates about 70% of the Bridger-Teton National Forest is infested with bark beetles. "it’s very prevalent," she said. Mountain Pine Beetle only affects pine trees (Lodgepole, Ponderosa, White Bark and Lumbar pines) and the Douglas Fir beetle affects only Douglas Fir trees. She said the infestation started around 2001 in Kemmerer and worked its way quickly northward all the way to the Teton Wilderness. "Basically, bark beetles are everywhere on the Bridger-Teton National Forest," she said. "We’re pretty sure we’ll lost almost all of our White bark pine," Davy said.
Adult beetles bore into the live trees during the months of July, August and September, where they mate and lay eggs. The larvae hatch over the winter and eat the inside of the bark, eventually killing the tree. "When you see the pitch tubes coming out of the tree trunk, the tree is dead, it just doesn’t know it yet." The larvae leave the tree as young adults between May and July looking for another tree to infect.
Forest managers are working to try and repel the beetles in high visibility public use areas on the forest, such as the campgrounds. Tree trunks are being sprayed with chemical to repel the beetles from trees in the campgrounds. "You have to spray before the bark beetles enter the tree," she said. Chemical must be sprayed over the course of a couple of summers on each tree.
Davy said care must be taken if cutting down live trees that might still contain beetles and using the wood for firewood. Logs should be moved out to an open area and have the bark stripped off to expose the inner bark to drying weather and hot sun. Some places recommend covering split wood with tarps to trap the beetles inside and let the sun bake them to kill them. "If the tree has red needles or no needles, those beetles are already gone," she said. Pheromone packages are available which are designed to repel beetles from the tree.
Homeowners with concerns are urged to contact the Wyoming State Forester for more information. Locally, the company Tree and Lawn Care (Kay Malkowski) provides tree spraying services, 307-859-8629.