| Title |
Investigators | Department | Objectives | Approach Keywords | Progress Reports | Impact Statements | Publications | |
Project * COL00203A(See Project History for COL00203) |
|
| Title | Interactions among Bark Beetles, Pathogens, and Conifers in North American Forests |
| Investigator(s) | Jacobi, WR; |
| Department | Bioagricultural Sciences and Pest Mgmt. |
| Objectives | 1) Characterize the role of biotic and abiotic factors in predisposing trees to bark beetle attack and subsequent mortality. |
| Approach | We will use the models developed for predicting white pine blister rust on limber pine to predict the association of mountain pine beetle and the risk of beetle damage. Surveys and GIS based landscape scale analysis will be utilized to develop risk models for bark beetle damage. |
| Keywords | Mountain pine beetle, White pine blister rust, Limber pine |
| Progress Reports | |
| 2005 | Problem: Recent fires in the Black Hills of South Dakota have led to eruptive populations of wood borers. Large populations prompted questions ranging from which species of wood borers are present, which traps and chemical attractants capture the largest number of wood borers to be able to monitor populations, what tree conditions are preferred by wood borers and are mountain pine beetle-infested trees and fire-killed trees colonized at different rates? Study methods: To develop monitoring techniques for wood borers in ponderosa pine in the Black Hills, two trap designs and four chemical attractants were tested and species determined in burned areas. Modified panel and funnel traps were tested in combination with chemical attractants including the wood borer standard (ethanol and X-pinene), standard plus 3-carene, standard plus ipsenol, and standard plus ipsdienol. To determine tree conditions that correlated with wood borer presence under the bark, trees in areas of moderate, high and severely burned fire areas were surveyed, within one-, two-, and three-year-old fires. Results: Funnel traps were more efficient or as efficient in capturing wood borers as panel traps. More wood borers were caught using treatments containing attractants than control treatments (no chemical attractants). Trap catches of the family Cerambycidae increased by adding Ips spp. pheromones, ipsenol or ipsdienol, or an additional monoterpene, 3-carene, compared to the wood borer standard. Eighteen cerambycid species, fourteen buprestid species and five siricid species were collected over the summers of 2003 and 2004. Flight trap data indicated that some species were present throughout the summer, where others flew in the beginning or end of the summer. In general, trees with needles 100% scorched or consumed had significantly more wood borers based on the presence of egg niches, larvae and holes than trees with green needles and fire age did not affect wood borer densities. Trees sampled in two- and three-year-old fires contained more egg niches present on the north side than the south side of trees, yet more entrance and exit holes were present on the south side in one- and three-year-old fires. The probability of wood borer presence was modeled by classification trees. Tree injury was an important predictive variable in trees with green needles, while tree size was an important predictive variable in trees with 100% scorched or consumed needles. |
| 2006 | Problem: Is there a relationship between mountain pine beetle attacks and dwarf mistletoe on Front Range ponderosa pine trees? Study methods: A random ground survey was conducted to determine the frequency and severity of Southwestern dwarf mistletoe (Arceuthobium vaginatum subsp. cryptopodum), mountain pine beetle (Dendroctonus ponderosae), and Ips spp. within Colorado's northern Front Range ponderosa pine (Pinus ponderosa var. scopulorum). The study area was bisected by the northern range limit of southwestern dwarf mistletoe (DM). A total of 833 (0.04 ha) plots, with 308 plots in the non-DM region and 525 plots (144 infested with dwarf mistletoe) in the DM region, were established in the Canyon Lakes Ranger District, Roosevelt National Forest, Colorado. Results: Significantly more mortality due to mountain pine beetle occurred in the DM region (18.1 stems/ha + 2.6 se) than the non-DM region (3.3 + 1.0 se). The same was true with mortality due to Ips spp. in the DM region (8.7 + 2.5 se) than the non-DM region (0.2 + 0.14 se). Significantly higher incidence of mountain pine beetle occurred in plots with the highest dwarf mistletoe ratings (80.81 + 14.19 se) than those plots with light (10.6 + 2.7 se) or no dwarf mistletoe infestation (7.3 + 1.5 se). These results strengthen the idea of bark beetles utilizing pockets of stressed trees in endemic populations. |
| Impact | |
| 2005 | Information from this project will help forest managers improve strategies and tactics for management of wood borers and wild fires in the Black Hills National Forest. Results also have relevance to many other locations. |
| 2006 | This information will provide forest managers with the data to make science based decisions on managing ponderosa pine in regard to the disturbance agents of mountain pine bark beetle and dwarf mistletoe |
| Publications | |
| 2005 |
Kallas, M. A., Reich, R. M., Jacobi, W. R., and Lundquist, J. E. 2003. Modeling the probability of observing Armillaria root disease in the Black Hills. Forest Pathology 33:241-252. |