Trees looking a little haggard? Blame it on drought stress

Trees looking a little haggard? Blame it on drought stress
An example of drought stress (photo courtesy of Oregon State University's Extension Service).

PORTLAND, Ore. - Some of Oregon's trees aren't faring so well this spring, especially the Douglas first and other conifers in the northwestern part of the state.

"My best explanation is drought stress," said Brad Withrow-Robinson, a forester with the Oregon State University Extension. "We had a pretty hard end of summer last year - no rain until mid-October - then boom! It was winter."

Classic signs of drought stress include dead treetops and flared-out branches.

Because the dry conditions that led to the stress didn't occur until late in the growing season, the effects didn't show up until now. And the recent warmer-than-average weather "seems to have made it more sudden and dramatic," Withrow-Robinson said.

The Willamette Valley can be a challenging environment for trees.

"Many of our soils in the valley are poorly drained, which is hard on most of our conifers, and other soils are fairly shallow and cannot hold much water," Withrow-Robinson said. "Also, our summers are hotter and drier than in the mountains."