Drought impacts on forest health – Forester presents report to Chaffee County

Shaver said drought plays a big part in the condition of unhealthy tree stands right now. 

Drought conditions in 2021 resulted in a low snowpack in spring and less snowmelt last year across much of Colorado. This lack of snowmelt stressed trees, leaving them more susceptible to insect attack. 

Shaver said snowpack in the Arkansas Basin was 75 percent of normal on June 1, 2021.

Shaver said trees take up about 70 to 75 percent of their water from snowpack, and low snowpack means more stress on trees.

To address forest health, several thinning projects are in the works for 2022.

Already completed are the Coyote Valley Road Project (80 acres) and the Methodist front project, phase 2 (138 acres) 

Ongoing in 2022 are projects to thin about 90 acres on Poncha Pass, about 129 acres on Little Cochetopa Pass and an 80-acre fuel break at the base of Mount Princeton.

Those projects are expected to be underway in late summer and early fall.

Shaver said the Poncha Pass project will focus on clearing Douglas fir affected by western spruce budworm or already killed by Douglas fir beetle. 

The thinning process will leave a few seed trees and will hopefully provide room for replenishing the ponderosa stand in the area.

“It’s good that we have species diversity,” he said.

Shaver told commissioners spruce beetle remains the most deadly forest pest in Colorado. 

Last year approximately 53,400 acres of forest were affected across the state. 

Across Colorado in 2021, spruce beetle affected 53,000 acres, Douglas fir beetle 8,000 acres and western spruce budworm 92,000 acres.

In Chaffee County in 2021 spruce beetle affected approximately 12,000 acres and Douglas fir beetle about 50 acres, although Shaver said he thought that figure was low, and western spruce budworm about 8,300 acres.

Shaver said he has seen Douglas fir beetle activity picking up in the Chalk Creek drainage area and on the top of Poncha Pass. 

“I think this is going to be the next beetle we’re going to have to defend against. It definitely won’t be as widespread as the spruce beetle – we do not have the amount of acres of Douglas fir that we have spruce,” Shaver said. 

Shaver said the western spruce budworm takes a while to kill large mature trees, but his big worry with the pest for Chaffee County is that it weakens the defense of Douglas firs. 

“It does hit the Douglas fir heavily, even though it’s called western spruce budworm, and could increase the possibility of Douglas fir beetle activity in weakened trees.

In the wake of the historic 2020 Glenwood Canyon fires and resultant post-fire mudslides, flooding and charred mountainside, and the 2021 Marshall Fire, the most destructive wildfire in state history in terms of insured losses, the call from the State Forest Service is to “heed the wake-up call from these fires by reducing wildfire fuels and preparing communities for fire.”