Posted on: July 9th, 2009

Pine beetles (mountain pine beetle (MPB) and Ips beetles) are native to our forests, but their populations are on the increase due to climate change and the unhealthy state of our forests. Climate change has made for warmer winters, so more beetles are surviving the winters. Our trees are stressed due to old age, drought, and high density, making them less able to defend themselves from beetle attack. An MPB epidemic is heading our way, and the experts predict that none of our lodgepole pine will survive. We may be able to save some of our ponderosa pines, however, by acting now to thin those forests, thereby reducing density and increasing tree vigor.  CWPP projects aimed at reducing wildfire risk through tree thinning will also increase forest health and beetle resistance.  Once we have done our best to create a healthy forest, non-toxic products like verbenone may help protect our trees.

Unfortunately, the recent increase in beetle populations means that the logs and slash produced by these projects must be managed appropriately, adding to the cost. In addition, beetle-infested trees should be removed before the beetles reproduce and fly to attack new trees, also adding to the costs of forest management. For more information about pine beetles, how to manage thinning projects appropriately, as well as how to recognize and get rid of “hot” beetle trees, please read on.

Thinning Projects and Beetles

Ironically, by thinning our forests we can actually make the beetle problem worse if we don’t properly manage the timing of the work and what we do with the downed trees and slash (biomass). During their summer flight time, mountain pine beetles (MPB) are attracted to areas with fresh cut wood, so cutting should be avoided in the summer unless wildfire risk reduction concerns override beetle concerns. During the spring and summer, the Ips beetle is active and will colonize freshly cut logs and slash. Green wood and slash need to be either removed from the area or chipped within 2 weeks to disrupt the Ips lifecycle. So, the best time to do thinning is in the fall, late September or later. At this time, green logs can be left in the sun to dry out over the winter. Slash can be left to dry out and/or piled for burning in the winter or early spring. Click here for more information on pine beetles.

What to do with “Hot” (Beetle-infested) Wood

First, how do you know if the wood is hot? If you have an all or partially red -needled tree, it is either dead or dying. If the problem is due to beetles you will likely see one or more of the following: pitch tubes on the bark (popcorn sized and shaped globs of sap), sawdust (frass) around the base of the tree and/or on the pitch tubes, exit holes in the bark about the size of a pencil tip perhaps accompanied by signs of woodpecker damage (bark removed, larger holes in the bark). Not all hot trees will show these signs, however, so it is best to err on the side of caution. You have basically two options for dealing with hot trees: you can either strip the bark off the tree or you can transport it to a county sort yard. Slash must either be chipped or burned (permit needed) or taken to a county sort yard. Solar treatment by wrapping the wood in plastic is no longer thought to be effective

Edie’s Beetle Story

I remember when the beetles arrived in my backyard. It was August of 1972, during the last Mountain Pine Beetle epidemic. A fierce lightning storm raged in the sky above my house. A bolt of lightning leaped from the sky, striking one of my neighbor’s Ponderosa pine trees. His four trees and two of my trees were a group divided only by my fence. When I went out after the storm to look for damage, I saw a gash cutting through the bark on one of the trees to the clean white wood underneath. I smelled the fresh sap oozing from the wound. Fear entered my heart. I knew that beetles are attracted to an area by the smell of fresh sap. The beetles would come! How could I save my trees from destruction? I loved my trees. I went into the house and cried.

Next morning, I went to check on the trees. Even before I reached them, I heard the beetles chewing. Globs of sap, sprinkled with sawdust, peppered the tree trunks as the beetles burrowed their way in to the trees. My neighbor’s four trees and my four trees in the backyard were all under attack by the beetles. My neighbor, a new arrival from sunny, urban California, obtained some Lindane and immediately sprayed his trees. I tried to stop him from using the poison. I told him that Lindane was not meant to be sprayed in the open or on standing trees. It was to be sprayed on the trees after they were cut down and covered with plastic. I told him that Lindane had a half-live of seven years, that it was very toxic to the environment, that it could cause kidney damage in humans. I wasted my breath. He would not listen to me. Next morning I saw two woodpeckers feasting on my neighbor’s poisoned beetles. I threw stones at them. “Come over and eat my beetles. I have organic beetles,” I shouted. But they didn’t listen either. They only invited their friends to come and join them at the banquet.

By next summer, my neighbor’s trees were dead, my four trees in the backyard were dead, and the population of woodpeckers, flickers, and nuthatches diminished. My two grandfather trees in the front yard survived. I hang suet, every winter, in the biggest tree to encourage the woodpeckers and nuthatches to visit. I rejoice each time I see them at my trees. I call it my beetle control.

Since that time, it has been my duty to remind everyone that sap attracts beetles, and while we can not control lightning, we can and should control when we use our chainsaws. If we are cutting during the beetles’ summer flight time, we are increasing the chance that beetles will attack and kill neighboring trees. It is all a matter of timing. Yes, I am emotional about the trees. I want to save the trees, as many as we can!!

Edie Eilender is a long-time Gold Hill resident and chair of the GHTM Forest Management Committee