Into the forest, a big wind blew, breaking the old hemlock’s heart…

broken hemlock

Brown rot is responsible for this hemlock snapping.

Last Friday, major winds buffeted the region and, right outside our cabin window, we witnessed some of the collateral damage: A tall and solitary hemlock snapped and tumbled to the earth. We saw it fall, the whole spectacle frightening and surreal. Thankfully, the tree came down just across our property line where no structures, vehicles or people were in the way. But what of all those elderly hemlocks that do surround our cabin? Should we worry about them during wind events?
One quarter of Western hemlocks are subject to heart rot, and the tree that fell outside our window suffered from brown rot.
This condition is caused by a fungi that destroys cellulose, leaving crumbly brown lignin. The tree snapped twenty feet up, where the brown rot began. The breakage allowed us to see that the brown rot infected the xylem (or heart) of the tree for nearly an additional fifteen feet. The additional 45 feet of living tree weight above the rot was too heavy to hold on this faulty foundation. Last week’s powerful winds sent it crashing down.
ndian paint fungus is the most prevalent fungus responsible for brown rot in the hemlocks of our region. The fungus usually enters through branch stubs that contain heartwood. Proper pruning and dead-wooding of limbs are good measures to prevent infection. If branches are properly pruned – and existing stubs are cut back, closer to the trunk – the tree is allowed to compartmentalize the wound. This mitigates pathogen entry points.
If your hemlocks look healthy, they probably are healthy. But if you have concerns – or have noticed exterior signs of rot – please contact us for an assessment.