Tree Killers

While on a trip to Colorado this past summer I learned about the Pine Beetle. This pest, no bigger than a grain of rice, is killing acres and acres of forest from Mexico to Canada. I swear half the trees I saw were dead. I just read an article in the New York Times about these killer bugs.

The black, hard-shelled beetle, the size of a fingertip, drills through pine bark and digs a gallery in the wood where it lays its eggs. When the larvae hatch under the bark, they eat the sweet, rich cambium layer that provides nutrients to the tree. They also inject a fungus to stop the tree from moving sap, which could drown the larvae. That fungus stains the wood blue.

“The Latin name is Dendroctunus, which means tree killer,” said Gregg DeNitto, a Forest Service entomologist in Missoula, Mont. “They are very effective.”

To fend off the bugs, trees emit white resin, which looks like candle wax, into the beetle’s drill hole. Sometimes the tree wins and entombs the beetle. Often, though, the attacker puts out a pheromone-based call for reinforcements and more of the beetles swarm the tree. In a drought the tree has trouble producing enough resin, and is overwhelmed.

These trees can't win! It's a terrible problem that many people don't know about. The dead trees are worrying the tourism industry, as many ski areas have cut down entire forests.

It will be interesting to see how the ecosystems shift over the years with this phenomenon. I'll be watching...will you?