It seems extraordinary that fire, the archenemy of the lodge-pole pine, should so largely contribute to the forest extension of this tree. It is not only one of the most inflammable of trees but it is easily killed by fire. Despite these weaknesses, such are the remarkable characteristics of this species that an increase in the number of forest fires in the West will enable this tree to extend its holdings; on the other hand, a complete cessation of fires would, in time, almost eliminate it from the forest! The lodge-pole pine (_Pinus contorta_, var. _Murrayana_) lives an adventurous frontier life, and of the six hundred kinds of North American trees no other has so many pioneer characteristics. This species strikingly exhibits some of the necessary requisites in trees that extend or maintain the forest-frontier. The characteristics which so largely contribute to its success and enable it to succeed through the agency of fire are its seed-hoarding habit and the ability of its seedling to thrive best in recently fire-cleaned earth, in the full glare of the sun. Most coniferous seedlings cannot stand full sunlight, but must have either completely or partly shaded places for the first few years of their lives. Trees grow from seed, sprouts, or cuttings. Hence, in order to grow or to bring back a forest, it is necessary to get seeds, sprouts, or cuttings upon the ground. The pitch pine of New Jersey and the redwood of California, whether felled by fire or by axe, will sprout from root or stump. So, too, will the aspen, chestnut, cherry, cottonwood, elm, most of the oaks, and many other kinds of trees. The extensive areas in New Brunswick and Maine that were cleared by the fires of 1825 were in large part at once regrown with aspen, most of which sprouted from the roots of burned aspens. Willow is easily propagated from a short section of the root, trunk, or limb. These sections may be broken from the tree by accident, be carried miles down-stream, lodge on shore or shoal, and there take root and grow. Beaver dams made of willow poles are commonly overgrown in a short time with willow. Several years ago a tornado wrecked hundreds of willows along a Kansas stream. Each willow was broken into scores of pieces, which were carried and dropped along the track of the tornado. Countless numbers of them were stuck into the earth. Several thousand willow trees were thus successfully planted by this violent wind.