Learning about fire ecology

I recently went on a Deschutes Land Trust hike just west of Bend, OR to learn about fire ecology. The area we hiked in is known as the Skyline Forest. There were fires in this vicinity in 2010 and 2014 and together they burned about 6,000 acres. The area is currently privately owned but the Deschutes Land Trust has been trying to acquire it.

Our guide, Pete Caligiuri with The Nature Conservancy, informed us that this area has about the steepest environmental gradient in the world. In the Cascade Mountains the precipitation can be as high as 160 inches per year while less than 25 miles away, it can be as low as 10 inches per year. Plants respond to the extreme amount of variability in this gradient. In the past, fire and moisture limited the number of trees in the forest. Now there can be as many as 800-900 trees per acre in this area.

We looked around to see how many large stumps left over from timber harvesting we could see. There weren’t many at all. At one time this forest had the trees much more widely spaced. We noticed the high number of young trees with branches reaching down closer to the ground. There was also a thick growth of underbrush that included bitterbrush and manzanita. The forest floor was covered with pine needles and fallen branches. The closer spacing, higher number of shrubs, and accumulation of litter on the forest floor makes this forest more vulnerable to fire.

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