Beetle battle is on in communities, mountains

LARIMER COUNTY – It was only a year ago that forest officials and tree experts were hopeful that the mountain pine beetle infestation that has ravaged millions of acres of lodgepole pine trees in Colorado’s high country would likely not spread to Front Range communities.

Lodgepole pine trees – the beetle’s favorite nosh – grow mostly at high altitude and the general consensus was that trees in lower elevations would likely escape infection, as long as the beetles did not jump to another species.

But that hope was dashed last fall when residents of Fort Collins, Loveland and other towns and unincorporated areas began reporting the presence of pine beetle infestations in their ponderosa and Scotch pine trees.

Once arrived on the Front Range, the voracious bugs have rapidly established a foothold, helped by warmer-and-drier-than-usual weather and drought-stressed trees. In Fort Collins, for example, the number of infected trees has jumped from six in 2006 to 342-and-counting today.

“Around the end of August 2008 we started getting calls like crazy,´ said Ralph Zentz, Fort Collins’ assistant city forester. “We’re at around 30 trees that will die because of the beetle, but I haven’t looked at everything yet.”

Zentz said that’s about a 10 percent death rate among infected trees, with Scotch pines proving to be most tasty to the beetles. About 260 of the beetle-bit trees are Scotch pines, with about 70 ponderosa pines and the remainder – fewer than 15 – a mixture of other species.

How did the beetles get here and multiply so quickly? Zentz said it’s believed that swarms of the bugs were blown east from the high country last summer when they emerged from their lodgepole incubators.

“We think the wind was just perfect and swept some beetles up and over the Continental Divide,” he said. Zentz said clouds of beetles have been picked up on Canadian radar in swarms 30 miles across.

Dave Lentz, Larimer County forester, echoes Zentz’s assessment of the infestation sweeping down the eastern side of the Continental Divide. “This last year we’re seeing hundreds and hundreds of new hits (in the county),” he said. “It’s moved way east.”

Lentz said beetles have been detected throughout the forested areas of the county, including Stove Prairie, Glacier View Meadows, Cherokee Park and other populated mountain communities.

Controlling factors out of control

So how bad is it, and how bad is it likely to get?

First, Lentz notes that mountain pine beetles have always been with us and probably always will be. Warmer-than-average winters and drier-than-average summers over the last decade have allowed the bugs – whose populations are normally held in check by cold spells and healthy trees with high sap levels – to get a firm foothold in the high country and inevitably move into usually safer lower elevations.

Another controlling factor – wildfire – has largely been suppressed in recent decades, resulting in thicker groves of trees and bigger feasts for the beetles.

“There’s probably twice as many ponderosa pines in the forest than there should be,” Lentz said. But that might not be the case for long, he notes.

“We can’t say we’re going to lose every ponderosa pine, like with the lodgepole,” he said. “But we more than likely will lose a lot of them.”

Both Lentz and Zentz say they expect the battle of controlling the beetle epidemic along the Front Range will take a long time but will eventually be won.

Both foresters say property owners can play a big part in turning the beetle tide by becoming more aware of what’s going on with their trees and taking preventive actions that include spraying uninfected trees they don’t want to lose and removing seriously infected trees.

Zentz said May is probably the optimal time to spray – just before hatched beetles fly off to munch on new home trees. Anti-beetle sprays are useless against embedded beetles but do provide a barrier to new infections.

“I think in the towns it’s very controllable,” he said. “We’re in a situation in town where preventative spraying will make a difference, and we know Scotch pine and ponderosa are susceptible.”

Lentz agrees that the urban pine beetle battle will likely be winnable in a short time with a concentrated effort by property owners. “We can clear up the towns – that’s not a big deal. But in the mountains, that’s a different story.”

Lentz said the battle in the county’s forests will be longer and much harder.

“We can count on 10 to 15 years of work dealing with this stuff,” he said. “If we can aggressively go after the new-hit trees, we can definitely have an impact. It will eventually peter out, but before that happens we’re going to lose a lot more trees.”

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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