HELENA — Friday, April 24, 2020 is National Arbor Day, a day intended to celebrate the importance of trees.
Montana's forests affect just about everyone in the state, either through recreation or wildfires.
It's been a decade since the peak of the mountain pine beetle infestation, which left millions of acres of Montana's forests with dead and dying trees.
“Over the last decade folk were really used to seeing mountain pine beetle activity, but as of now that activity has really diminished to natural occurrences,” explained Timber Management Office Sharron Scott with the Helena-Lewis and Clark National Forest. “So people may see really small pockets of red in lodgepole pine and ponderosa.”
Scott says the most prevalent insect activity the Helena-Lewis and Clark National Forest has right now is western spruce budworm.
The moth species is also one of the most destructive defoliators of coniferous forests in western North America.
“Typically, they don’t kill trees,” explained Scott. “Depending on the elevation you're at you may see a red hue across the landscape, and that's those bugs that are eating and defoliating trees.”
Scott says the budworms typically are present on douglas fir, whcih is also affect by another bug.
“The other insect we have active is douglas fir beetle, which is a little less aggressive that mountain pine beetle, and they really focus on larger diameter douglas fir,” said Scott.
Scott says the two species of insect combined can cause serious issues for the forest.
“The western spruce budworm defoliates them, and then when the douglas fir beetle comes it will kill the larger trees, which we really want to retain on the landscape,” said Scott.
The Helena National forest has some level of mortality in around 60 to 70 percent of the Forest’s stand.
Scott notes the regeneration of a forest takes time, but they have begun to see progress.
“Now we’re getting a fair amount of regeneration that’s coming up through that deadfall,” said Scott. “So what lodgepole pine needs to regenerate, they have serotinous cones, and those cones open when you get heat. So because of the sunlight and the open forest floor, and the intensity of all those downfall trees, we’re actually beginning to see regeneration.”
