Last week I had the good fortune to visit the Big Sky state of Montana. I stayed at a cabin at Georgetown Lake in the western part of the state with family who live in nearby Deer Lodge. Not surprisingly, we spent a lot of our time outdoors, fishing, hiking, biking and sitting on the porch. The wilderness in western Montana is beautiful, but it is suffering a shocking loss of its signature tree – the lodgeple pine. Everywhere you travel, you see huge tracks of the tress cut as though the area had just been clear cut. It is stunning.
The culprit is not an aggressive logging effort, but an insect, an infestation of beetles – lodgepole beetles and it’s changing the landscape of this beautiful countryside, serving another lesson in the impacts of climate change.
A popular tree throughout the Pacific Northwest and northern Rockies, the lodgepole pine is long, straight and lightweight and was a favorite for making log cabins and tee pees in earlier times. Now these trees are being devastated by a tiny beetle which according to the National Science Foundation, has infected more than six billion trees in the western United States and British Columbia since the 1990s.
The mountain pine beetle is a native insect that plays a natural role in regenerating pine forests in Western North America. This role is now in jeopardy because of changing weather patterns in Montana and other areas of the Pacific Northwest.
In the past, populations of this beetle were controlled naturally by the harsh winter weather in this rugged mountain area. Typically it takes 7 to 10 days of intense cold weather – 20 degree below zero or more – to kill the beetles. In past years, this was never an issue. Some beetles would survive, but many were killed off by the bitter cold winter weather.
Now the weather is changing. Winter is not as harsh in this part of the country as it used to be. It does not get as cold for as long as it had typically in past years. As a result, the beetles are thriving and continuing to wipe out huge tracks of lodgepole pine trees.
A study published in 2009 by a research group from several western universities found that the death rate of trees in western U.S. forests had doubled over the several decades driven in large part by higher temperatures and water scarcity brought on by climate change. One of the lead authors commented that longer and hotter summers in the west were subjecting trees to greater stress from droughts and insect infestation.
It’s hard to predict how these changes will transform the western landscape, but it’s not likely to be a pretty picture. I had no idea how climate change was impacting the western forests and I‘m glad I visited when I did. It It‘s not likely these forest will be regenerated in my lifetime.