Pine beetles emerge and seek live and green trees between mid-July and mid-September, according to the Colorado State Forest Service.
Dave Root, assistant district forester with the Woodland Park district, said Fall is the best time to assess trees for infestation.
“You’re trying to prevent the bugs from flying out of the tree next summer and attacking yet another tree or, as it sometimes works, three to five more trees next year,” said Root.
Root explained that female beetles carry a fungus that they pass along to the tree they inhabit. This fungus prevents the tree from being able to absorb water, causing the tree to turn brown and die.
To determine whether a tree is infected, a resident should look for pitch tubes. These are accumulations of sap, which is a trees’ natural defense. The tubes may be white to pinkish, and indicate an attack but may not necessarily mean the tree is fully infested.
A more definite indication would be the presence of boring dust, a reddish-brown dust, in bark crevices and on the ground near the tree base.
The trees may still appear green, even if they are infested.
“When the beetles get into the tree, the tree is dead. There is no way to save the tree once the beetles get into it,” said Root.
Once the beetles are detected, the tree needs to be treated.
There are two main treatments for infested trees, mechanical and solar.
The mechanical method includes cutting, bucking, splitting, chipping, peeling or burning the tree to kill the beetles.
The solar method is a slightly more complex method. It involves wetting infested logs, and then covering them with a layer of plastic and sealing the edges with dirt. Root said this will create a greenhouse-like effect, allowing temperatures beneath the plastic to reach a temperature at which the beetles cannot survive.
Homeowners with questions and concerns regarding beetles on their property can call the Woodland Park District Forest Service office at 719-687-2951.
Root said forest service representatives are available to make house calls, inspecting trees and determining treatment plans.
“We can come out and not only look at the tree and determine whether it’s infested or not, but we can look at the entire forest and start working with you and determine what sort of thinning or what kind of forest management treatments that you many need to do to prevent problems in the future,” said Root.
Root said advice over the phone is free, but there is a $50 fee associated with on-site inspections.
Root added that those living near the Waldo Canyon burn scar should be especially vigilant. He explained pine beetles tend to prey on weakened trees, like those impacted but not killed by the wildfire.
“Those that were just injured and are still alive are going to be much more susceptible to attack by pine beetles and that’s an area of concern that we’ll have to watch for another four to five years,” he said.
There is a preventative spray that can be applied to trees in the springtime that will repel the beetles. More information on the spray can be obtained here.
For more information on pine beetles in Colorado, click here.