| Publication Type: | Journal Article |
| : | 2008 |
| Authors: | P. E. Maloney, Smith, T. F., Jensen, C. E., Innes, J., Rizzo, D. M., North, M. P. |
| Journal: | Canadian Journal of Forest Research |
| Volume: | 38 |
| Pagination: | 3011-3020 |
| Date Published: | December |
| Type of Article: | Article |
| : | 0045-5067 |
| : | Dendroctonus jeffreyi, Dendroctonus ponderosae, Dendroctonus valens, Scolytus ventralis |
| : | Fire and thinning restoration treatments in fire-suppressed forests often damage or stress leave trees, altering pathogen and insect affects. We compared types of insect-and pathogen-mediated mortality on mixed-conifer trees 3 years after treatment. The number of bark beetle attacked trees was greater in burn treatments compared with no-burn treatments, and in some cases, larger pine trees were preferentially attacked. Restoration treatments are not expected to change the trajectory of spread and intensification of dwarf mistletoe. Thinning treatments may have provided a sanitation effect in which large leave trees have lower levels of dwarf mistletoe. Although thinning treatments are known to exacerbate root disease, 12% of cut stumps were infected with root pathogens (Armillaria gallica and Heterobasidion annosum). Treatments increased Ribes (alternate host for white pine blister rust) frequency and abundance, which may have very localized impacts on white pine blister rust dynamics. In some instances, fire, insects, and pathogens appear to conflict with forest restoration goals by reducing the percentage of pine and producing proportionally higher rates of tree mortality in large-diameter size classes. To better understand the long-term effects of restoration treatments on pathogens and insects, continued monitoring over the course of varying climatic conditions will be needed. |