Conservative approach to hazard tree operations includes reassessing hundreds of trees
The September 2020 wildfires, which burned more than one million acres across Oregon, left tens of thousands of dead and dying trees along our state’s highways and public places. These large areas of burned trees blocked roads, cut off cleanup efforts and posed an imminent threat to public safety.
Debris Management Task Force (Task Force) crews moved swiftly to assess and remove hazard trees to ensure that no more lives would be lost and move Oregon toward reopening our open spaces. Teams of arborists worked to evaluate and mark hazard trees as efficiently as possible to ready them for removal, while trying to save as much of the flora as safety allowed.
When they were originally marked – between January and April of this year – several hundred trees statewide showed signs that they had at least a slim chance of survival. Trees may have demonstrated a greenery crown scorch right at the minimum threshold or a bark char marginal enough to give it a possibility of pulling through.
“We took a very conservative approach to marking trees for removal,” explained Task Force Senior Forest Analyst Reggie Fay. “If there were not obvious signs that a tree was going to die in the next three to five years, we put it on the watch list.”
The “watch list” includes several hundred trees, primarily along the OR-138E, OR-126, OR-22 and OR-224 corridors, that were on the bubble of needing to be removed.
Certified arborists will be reassessing and re-marking the watch list trees over the coming weeks. In some cases, trees will show enough signs of survival (mainly needles that are staying green) to be deemed okay to leave standing. Many, however, will demonstrate worsened signs that they will die completely within the next three to five years and will need to be marked for removal.
As Fay explained: “It is not a tremendous number of trees [compared to the total number of hazard trees statewide], but they tend to be the biggest and the tallest; the ones that had higher crowns and were more resilient to the fire.” Smaller trees are engulfed more easily and burn much quicker with less chance of survival.
“The goal was never to clear cut or remove any more trees than absolutely necessary,” Fay explained. “We decided to take the approach of ‘let’s give these trees five or six more months, let’s see how they do over the summer, and then we will reassess them individually.’”
The hope, of course, was that these trees would be able to get enough nutrients to survive and not become a threat to public safety. Recent hot temperatures and a lack of rainfall have made conditions more difficult for trees already fighting to survive.
Fay explained that it is inconclusive as to whether these trees would have survived even without the June heat wave and ongoing drought conditions statewide, but he acknowledged that “it certainly couldn’t have helped.”
“We were giving these trees every chance to pull through,” Fay said. “Almost all of us working in these fire areas also live in these communities. We really wanted to see them survive.”