The mountain pine beetle, Dendroctonus ponderosae, is a significant pest of lodgepole pine in British Columbia (BC), where it has recently reached an unprecedented outbreak level. Although it is native to western North America, the beetle can now be viewed as a native invasive because for the first time in recorded history it has begun to reproduce in native jack pine stands within the North Am...

Low-elevation ponderosa pine (Pinus ponderosa Dougl. ex. Laws.) forests of the northern Rocky Mountains historically experienced frequent low-intensity fires that maintained open uneven-aged stands. A century of fire exclusion has contributed to denser ponderosa pine forests with greater competition for resources, higher tree stress and greater risk of insect attack and stand-destroying fire. A...

This study was conducted in Central Europe (Poland) pine forests that were subjected to the process of resin harvesting 1970s. Forty trees designated for study, which had one or two blazes. The objectives experiment determine effect tapping on changes annual growth, wood density, and mechanical strength damaged trees. Resin affected development dynamics, especially with a single blaze. In addit...

Maritime pine (Pinus pinaster Ait.) is native to the western Mediterranean basin and has an economic importance in southwestern Europe. This based on use of its wood construction, furniture, paper industries. Bark other parts plant, such as resin, needles, cones, are by-products with potential industrial application. These tree stand out because presence secondary metabolites, main ones being p...

Warming climate has increased access of native bark beetles to high-elevation pines that historically received only intermittent exposure to these tree-killing herbivores. Here we show that a dominant, relatively naïve, high-elevation species, whitebark pine, has inferior defenses against mountain pine beetle compared with its historical lower-elevation host, lodgepole pine. Lodgepole pines res...

The content and distribution of stilbenes and resin acids in Scots pine (Pinus sylvestris) and spruce (Picea abies), sampled in central Norway, have been examined. The contents of pinosylvin stilbenes in pine heartwood/living knots were 0.2-2/2-8 %(w/w). No stilbenes could be detected in spruce (Picea abies). The resin acid contents of pine sapwood/heartwood and knots were 1-4 and 5-10 % (w/w),...

Xylem resin-a supersaturation of resin acids in terpenesappears to play a paradoxical role in the relation of the Pinaceae to tree-killing bark beetles. It has been suggested as the agent responsible for the susceptibility of this coniferous family to beetle attacks. And, at the same time, it has been linked with the ability of the Pinaceae to resist bark beetles. The hosts of treekilling bark ...

Warmer climates induced by elevated atmospheric CO(2) (eCO(2)) are expected to increase damaging bark beetle activity in pine forests, yet the effect of eCO(2) on resin production--the tree's primary defense against beetle attack--remains largely unknown. Following growth-differentiation balance theory, if extra carbohydrates produced under eCO(2) are not consumed by respiration or growth, resi...

Repeatability was estimated for constitutive oleoresin yield measurements in 10 stands of three species of pines native to southeastern United States. Trees of these species that discharge large quantities of oleoresin upon wounding are considered to be most resistant to attack by southern pine beetle (Dendroctonus frontalis Zimmermann). Oleoresin yield is usually measured from one or more smal...