Mountain Pine Beetle
Introduction
Mountain pine beetles (MPB) are the most important insect pest of
Colorado's pine forests. MPB often kill large numbers of trees annually during outbreaks. Trees that are not growing vigorously due
to old age, crowding, poor growing conditions, drought, fire or mechanical damage, root disease and other causes are most likely to
be attacked. For a long-term remedy, thin susceptible stands. Leave well-spaced, healthy trees. For short-term controls, spray, cover,
burn or peel attacked trees to kill the beetles. Preventive sprays can protect green, unattacked trees.
Mountain pine beetle (MPB),
Dendroctonus ponderosae, is native to the forests of western North America. Periodic outbreaks of the insect, previously called the
Black Hills beetle or Rocky Mountain pine beetle, can result in losses of millions of trees. Outbreaks develop irrespective of property
lines, being equally evident in wilderness areas, mountain subdivisions and back yards. Even windbreak or landscape pines many miles
from the mountains can succumb to beetles imported in infested firewood.
Mountain pine beetles develop in pines, particularly ponderosa,
lodgepole, Scotch and limber pine. Bristlecone and pinyon pine are less commonly attacked. During early stages of an outbreak, attacks
are limited largely to trees under stress from injury, poor site conditions, fire damage, overcrowding, root disease or old age. However,
as beetle populations increase, MPB attacks may involve most large trees in the outbreak area.
A related insect, the Douglas-fir beetle
(D. pseudotsugae), occasionally damages Douglas-fir. Most often, outbreaks are associated with previous injury by fire or western
spruce budworm. (See Colorado State University Extension fact sheet 5.543, Western Spruce Budworms). Spruce beetle (D. rufipennis)
is a pest of Engelmann and Colorado blue spruce in Colorado. Injured pines also can be attacked by the red turpentine beetle (D. valens).
Signs and Symptoms of MPB Attack
Popcorn-shaped masses of resin, called "pitch tubes," on the trunk where beetle tunneling begins.
Pitch tubes may be brown, pink or white. Boring dust in bark crevices and on the ground immediately adjacent to the tree base.
Evidence
of woodpecker feeding on trunk. Patches of bark are removed and bark flakes lie on the ground or snow below tree.
Foliage turning
yellowish to reddish throughout the entire tree crown. This usually occurs eight to 10 months after a successful MPB attack.
Presence
of live MPB (eggs, larvae, pupae and/or adults) as well as galleries under bark. This is the most certain indicator of infestation.
A hatchet for removal of bark is needed to check trees correctly
Bluestained sapwood. Check at more than one point around the tree's
circumference.
Source and For More Information go to:
http://www.ext.colostate.edu/pubs/insect/05528.html
MOUNTAIN PINE BEETLE RESOURCES
Estes
Valley Residents: For free inspections and advice for spraying, please contact these folks:
Tracey Feagans of the Town of Estes Park
at 577-3588, Wendell Amos 586-5524, or Larimer County Forester, Dave Lentz, at 498-5765. The Colorado State Forest Service in Fort
Collins also is available for advice and assistance. That number is 491-8660.
Recommended spray companies (as per Estes Park Trail
newspaper article July 9 2008) based out of Fort Collins or Denver:
Fine Tree Service Ft. Collins
(970) 377-2851
Fort Collins Tree
Care Ft. Collins
(970) 484-3084
Kincade Lawn & Tree Ft. Collins
(970) 484-8733
Swingle Lawn & Tree Ft. Collins
(970) 221-1287
Denver (303) 337-6200
Tree Consultation/Removal Services in Surrounding Areas:
A Cut Above Forestry: Summit Co. (970) 453-9154
Eagle
Co. (970) 949-7079