Topics

With the severe drought, I am seeing increased tree mortality.

Question:
With the severe drought, I am seeing increased tree mortality. Frequently saplings that are under the canopy of large trees. In some areas I am seeing increased mortality of mature firs and pines. I have previously been focused on thinning to reduce ladder fuels and to reduce competition for water. How should small forest owners react to increased tree mortality? Should we stay the course with stand improvement work like thinning, or should we focus on removing dead trees?

Answer:
In severe drought conditions, even trees that appear seemingly healthy can fall victim to bark beetle attack. The single best way to combat this problem is control of tree spacing, making sure that each tree has adequate space as soil moisture is scarce.

When beetle damage does appear, usually during early- to mid-spring, look for pitch extrusions caused by boring beetles. The trees may lose some of the green color to fade to a duller green, a sign that they are under stress. If the needles are orange, it is likely that the beetles have moved on to other nearby trees.

A salvage operation can remove infected trees and return some money to the landowner, but often the cost in removing the trees is more than the monetary return, especially if the infected trees are widely scattered.