FORESTRY UPDATE 5-3

By Gary Allen Burns

Southern pine beetles (SPB) attack trees stressed by drought or other factors. They can overwhelm trees and kill large patches of timber. Pitch tubes develop where the beetles tunnel into the bark. These tubes are larger than those of Ips bark beetles, but smaller than the quarter-size tubes of turpentine beetles. SPB pitch tubes are usually found in the bark crevices, while Ips pitch tubes are not only in the crevices, but also on the bark plates.

The best defense against bark beetles is sound forest management – controlling competing vegetation and matching the proper tree species to the site. Dense stands can become “bug bait.”

They should be thinned to reduce the residual basal area