The mountain pine beetle has infested and killed over half the lodgepole pine forest in the centre of the province an area larger than England.
The boreal forest is mainly composed of jack pines, which lack the natural defences of the lodgepole pine; this has evolved in coexistence with the beetles.The hope is that the infestation will stall on Alberta's eastern border with Saskatchewan, where large stands of jack pine are scarce.
But Mr O'Toole says that other forests, such as the lodgepole pine forests common in Wyoming, Montana and elsewhere, are genetically programmed to burn to the ground once a century or so, as happened in Yellowstone in 1988.
The accused are said to have taken him to the outskirts of town, tied him to a split-rail fence of lodgepole pine, and repeatedly fractured his skull with the butt end of a.357 Magnum.
Higher elevations are cool and temperate, with stands of lodgepole, ponderosa, and Jeffrey pines.
All North American tree species are distributed across the continent except jack pine (Pinus banksiana), lodgepole pine (Pinus contorta), and balsam fir (Abies balsamea).
About four-fifths of the park's area is forested, and the vast majority of the tree growth consists of lodgepole pines.
Of the park's 9,000 square km (about 3,500 square miles), much of it dominated by lodgepole pine (Pinus contorta), more than half were scorched, and approximately 36 percent of the park was burned.
The subalpine forests comprise western hemlock, lodgepole pine, western red cedar, white spruce, and Engelmann spruce.
North American coniferous forest is dominated throughout by white spruce, black spruce, and balsam fir, although lodgepole pine and alpine fir are important species in the western section.
Some species, such as lodgepole pine (Pinus contorta), are polycyclic; they have several flushes from a single bud during the growing season.
