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Aerial spray attempts to control other members of the C. fumiferana complex evidently have not been directed to C. lambertiana. This is specifically because high-level infestations have been sporadic in time and space, and have not persisted more than 2 or 3 years (Stark and Borden, 1965; McGregor, 1970). Also, lodgepole pine (Pinus contorta), the principal host tree, is not of high economic value that would warrant costs of control measures.
Economic impact to forestry production has not been documented. McGregor (1970) reported that vegetative terminals in the upper one-third of the tree canopy of Pinus contorta were infested and all the new season foliage was destroyed during outbreaks in Idaho and Montana, resulting in top-kill of the trees after 2 to 3 years. However, trees were not killed, high-level infestations did not persist, and adverse effects on lumber use were not reported. In an outbreak in the Sierra Nevada in 1963-1964, Stark and Borden (1965) reported infestation levels of female cones up to 90%. This outbreak was localized and did not persist. Larvae were difficult to detect in the same area in 1970 and 1979-1981 (JA Powell, University of California, USA, personal communication, 2004). Whether seed production during brief periods (a few years) has any effect on forest reproduction is doubtful. Stevens et al. (1977) stated that heavy defoliation could cause severe damage to infested Pinus ponderosa. They observed persistent (at least 3 years) defoliation by Colorado populations of C. lambertiana ponderosana to kill shoots and cause branch deformity. They found severe defoliation of individual groups of trees but did not observe effects on broad forest areas. Ponderosa Pine is much more important for lumber than the other pines used by C. lambertiana.