The trees are dying, their mortality rate doubling across the western forests in the last few handful of years. It doesn’t seem to matter—young or old trees growing at elevations high and low, pines and firs and hemlocks.
Photo attribution: Majorcascadia.
US Geological Survey scientists believe the cause of death is the warming climate—1 degree Fahrenheit over the last few decades. Only 1 degree but enough to trigger cascading consequences. New growth isn’t replacing the loss quickly enough to maintain equilibrium. Winter snowpack is less, snowmelt comes sooner, summer drought lasts longer. The longer, hotter summers invite insect that burrow into bark or browse on leaves.
“A doubling of death rates eventually could reduce average tree age in a forest by half, thus reducing average tree size,” said Nate Stephenson with the US Geological Survey and co-leader of the research team that documented their work in the article “Widespread increase of tree mortality rates in the western United States” recently published in Science magazine.
What does it mean when the forests die? I can’t imagine the loss of living in a world forested by naked snags and skeletal branches.
Strong to break dead things,
the young tree, drained of sap,
the old tree, ready to drop,
to lift from the rotting bed
of leaves, the old
crumbling pine tree stock.