Pine Reproduction Weevils, Hylobius pales (Herbst) & Pachylobius picivorus (Germar)

The pales weevil, Hylobius pales (Herbst), and the pitch-eating weevil, Pachylobius picivorus (Gennar), are common pests of young pines growing on recently cutover pine lands and Christmas tree plantations (Lynch 1984, Nord et al. 1982). They are infrequent to occasional pests of seed orchard trees (Dixon 1983), young pines growing in forest tree nurseries, and pines adjacent to wood-processing mills. Losses may range as high as 40% twig mortality in Christmas tree plantations (Nord et al. 1984), 60% seedling mortality due to P. picivorus alone in pine plantations (Thatcher 1960), and 90% seedling mortality due to H. pales alone (Nord et al. 1984). Adult feeding damage to young pines often varies along a gradient, i.e., those seedlings nearest disturbed trees, stumps, or slash material sustain the most damage while seedlings 100-200 feet away are usually lightly damaged. However, weevil feeding damage sometimes extends to seedlings or young trees up to 0.5 mile away. Generally, both species are present although their population ratios will vary depending on geographic location and season (Nord et al. 1984 ).