Monday, April 7, 2008

Ips Beetle Management

Proactive Treatment
Here at The Country Club were are very proactive in the treatment of our Ponderosa Pines that exist on the golf course. Each year we contract to spray all of the Pines as a preventive attempt to properly manage the Forrest. These insecticidal drenches are applied to the tree needles as well as the trunk and bark areas.

Symptoms of Ips Beetle Infestation
As adult Ips beetles enter trees and tunnel, a yellowish- or reddish-brown boring dust is produced and accumulates in bark crevices or around the base of the tree.
Small round holes in the bark of infested trees indicate the beetles have completed development in that part of the tree and the adults have exited. The presence of these holes peppering the bark show the beetles have moved to another part of the same tree or to neighboring trees.

These symptoms may be limited to parts of the tree, such as a single branch or the top. However unlike mountain pine beetle, infestation by Ips beetles does not necessarily mean the whole tree will die, but over time, attacks may progress as later generations “fill” the tree and then ultimately the host can die.

To prevent Ips beetle attacks, use practices that promote vigorous tree growth. Properly siting trees in landscape plantings is important to allow optimal growing conditions as the tree matures. Freshly-cut material that results from pruning or thinning practices should be removed from the vicinity of valuable trees. Never stack green or infested coniferous wood next to living coniferous trees.
Trees at risk of Ips attack include newly transplanted trees, trees suffering root injuries from construction, and trees surrounded by large breeding populations of Ips beetles. These types of trees can benefit from preventive insecticide applications.
Insecticides are used as drenching preventive sprays on the trunks and larger branches. These insecticides need to be applied prior to adult beetle infestation. (Remember that overwintering beetles begin emerging in spring as soon as daytime temperatures consistently reach 50 F to 60 F.) However, timing can be difficult to determine since Ips beetles can have multiple, overlapping generations and life cycles. Adults have been observed entering trees during warm days as early as late-February on through November. Because of this extended activity, two treatments (early spring and summer) may be needed to protect trees during high-risk conditions.

Ips Quick Facts...
• Ips is a common group of bark beetles that infests pine and spruce trees.
• Ips beetles rarely attack healthy trees. Most problems with Ips occur to newly transplanted pines or when plants are under stress.
• Several generations of Ips can occur in a season.
• There are 11 species of Ips beetles found in Colorado.

W. Cranshaw, Colorado State University Extension entomologist and professor, bioagricultural sciences and pest management; and D.A. Leatherman, Colorado State Forest Service entomologist (Retired). This fact sheet was produced in cooperation with the Colorado State Forest Service. 12/02. Revised 11/06.