Some fires swept so clean that they left behind no date of their ravages, but here and there the character of the forest and of the soil in which it stood made me feel certain that the growth had arisen from the ashes of a fire, and that I could tell the extent of the fire. In most localities the fire-killed forest is at once restored by nature. That ever enthusiastic sower, the wind, reseeds most burned areas within a year. Burns on the Western mountains commonly are covered with young lodge-pole or aspen within three years. There are a few dry wind-swept slopes or places left rocky for which years or even centuries may be required to re-earth and reforest. Some members of the Pine Family endure fire much better than others. The "big tree," the redwood, and the yellow and sugar pines will survive far hotter fires than their relatives, for their vitals are protected by a thick sheath of slow-burning bark. The Western yellow pine is one of the best fire-fighters in the forest world. Its vitals appear able to endure unusual heat without death, and it will survive fires that kill neighboring trees of other kinds. In old trees the trunk and large limbs are thickly covered with heat-and-fire-resisting bark. In examining a number of these old fellows that were at last laid low by snow or landslide or the axe, I found that some had triumphantly survived a number of fiery ordeals and two or three lightning-strokes. One pine of eight centuries carried the scars of four thunderbolts and seven wounds that were received from fires decades apart. The deciduous, or broad-leaf, trees resist fires better than the coniferous, or evergreen, trees. Pines and spruces take fire much more readily than oaks and maples, because of the resinous sap that circulates through them; moreover, the pines and spruces when heated give off an inflammable gas which, rising in front of a forest fire, adds to the heat and destructiveness, and the eagerness of the blaze. Considered in relation to a fire, the coniferous forest is a poor risk because it is more inflammable than a deciduous one. Another advantage possessed by broad-leaf trees lies in the rapid growth of their seedlings. Surface fires annihilate most tiny trees. Two-year-old chestnuts, maples, and, in fact, many of the broad-leaf youngsters, are three or more feet high, and are able to survive a severe fire; but two-year-old white pine, Engelmann spruce, or long-leaf pine are barely two inches high,--just fuzzy-topped matches stuck in the earth that perish in a flash from a single breath of flame.