Spruce Beetle in Logging Operations
The spruce beetle, Dendroctonus rufipennis, is a natural disturbance agent throughout the geographical range of spruce in North America. At endemic levels,spruce beetle normally infest downed trees, logging debris, decked timber, dying or stressed trees and only occasionally cause tree mortality. During periods of outbreak, beetles will attack and kill live trees causing widespread mortality. |
While conducting forest regeneration studies at the Marshal Creek clear cuts, the ES observed about 5000 logs piled on a landing deck. Pairs of students in the class were given the task of developing a methodology for estimation the population of spruce bark beetles by counting emergent holes found on these logs. They were also asked to give confidence levels for their population estimates. Pairs of students derived a number of different survey methods with different confidence levels. When we examined the results, most groups found 20 million plus or minus 3 million emergent holes.
The students concluded between the logs on the deck and those blown down at the margins of the clear cut represented a potential source for the expansion of the spruce bark beetle infestation in the region.
The students concluded between the logs on the deck and those blown down at the margins of the clear cut represented a potential source for the expansion of the spruce bark beetle infestation in the region.