Here come the beetles, no taste for local pines

There’s some good news for Front Range residents living in fear of a mountain pine beetle invasion that’s decimated millions of acres of lodgepole pine forests in the high altitudes of the Western Slope.

The voracious little buggers aren’t really that interested in the kinds of pine trees that grow on this side of the Continental Divide. That’s the reassuring message from Ingrid Aguayo, a forest entomologist for the Colorado State Forest Service.

Yes, it’s true that Timber Creek Campground in Rocky Mountain National Park was closed in April and will remain closed until July for removal of trees killed by the beetle epidemic. That makes the invasion seem all too near and frightening to many mountain area homeowners.

But, according to Aguayo, it’s the lodgepole pines that are the food of choice for the beetles, and lodgepoles mostly grow in the highest altitudes of the state.

“Right now we’re seeing it mostly with lodgepole pine,” she said. “On the Front Range it’s mostly ponderosa pine as the elevation goes down, along with some spruce and Douglas fir.”

But will the bugs start chomping on ponderosa if they begin to run out of lodgepole? Aguayo said the final verdict is still out on that one.

“That’s our concern,” she said. “Will it jump to ponderosa? At this point we really have not seen an outbreak in ponderosa pine.”

Aguayo said some beetle infestation is normal in stressed ponderosa pine trees, especially those infected with dwarf mistletoe – a parasitic fungus – or those hit by lightning at some point.

Front Range mostly spared

Aguayo said she doesn’t believe the pine beetle epidemic – which has raged on the Western Slope for 10 years and devastated lodgepole forests in Grand, Eagle, Jackson and Routt counties – will be anywhere near as bad on the Front Range.

“We have a little more (species) diversity on the Front Range,” she said. “I don’t think it’s going to be as rampant, but I think we’ll know either this year or next year.”

Several times in the summer, Aguayo boards a Forest Service plane and maps the areas of beetle infestation to check its spread. She said areas on the Western Slope are beginning to get harder to spot new beetle kill, with a sea of red-needled dying trees growing ever larger and larger.

So far, millions of trees on millions of acres are dead or dying, creating a tinderbox for lightning or human-caused wildfires.

The beetles bore under the tree bark to lay their eggs and then die, completing their life cycle. Aguayo said the beetles go through four larval stages of development and are particularly vulnerable to a cold winter when they’re first developing. They’re also especially vulnerable to a late spring cold snap when they’re changing into a pupa, she said.

Unfortunately, warmer-than-normal winters over the last decade have failed to kill the offspring, which have emerged to find huge amounts of food in the form of weakened, drought-stressed trees.

“They’re doing great,” Aguayo says of the burgeoning population of beetles. “All the stars are lined up for them.”

Thinning crowded forests

Aguayo said beetle kill and fire are the two most natural ways to thin forests that are becoming crowded and unhealthy. But natural fires have largely been suppressed, resulting in many trees living longer than normal with weakening defense mechanisms.

“I think in general we might have suppressed too many fires, but we have more and more people living (in mountainous forest areas), so there’s a challenge there,” she said.

About the only thing mountain residents can do is to be constantly vigilant about the health of their trees and spray or remove those that have been infected.

Aguayo said the infestation has resulted in more interest from homeowners on how to protect their trees. “It gives us as an agency a way to get out and educate people on forest issues,” she said.

Aguayo said budget constraints prevent forest service employees from visiting individual home sites to look at possible infestations, but she said the agency is happy to arrange workshops for neighborhood associations or other groups.

Aguayo notes that there has been some good news associated with the beetle epidemic. Wood killed by the bugs – which turns a light blue color – has become popular as an “exotic” furniture choice. “The furniture made from it looks beautiful,” she said.

Aguayo said those living in the path of the bugs might want to take a philosophical approach to the loss of some trees.

“All these trees are going to die eventually,” she said. “People ask me all the time about whether their property values will be affected by the beetles. The only example I can give is that some people in Grand County didn’t know they had a view of a lake or a mountain until the trees were removed.

“It all depends on the landowner’s perspective,’ she said.

Steve Porter covers agribusiness for the Northern Colorado Business Report. He can be reached at 970-221-5400, ext. 225, or at sporter@ncbr.com.

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