A careful examination around the margin of a burned forest will show the trees of surrounding kinds working in again. Thus by the time the short-lived aspens (and they are very short-lived on high land) have made a covering on the burned land, the surrounding kinds will be found re-established in the new forest, the seeds of the conifers, carried in by the winds, the berries by the birds, the nuts and acorns by the squirrels, the mixture varying more or less from the kinds which grew there before the fire. It is wonderful how far the seeds of berries are carried by birds. The waxwings and cedar birds carry seeds of our tartarean honeysuckles, purple barberries and many other kinds four miles distant, where we see them spring up on the lake shore, where these birds fly in flocks to feed on the juniper berries. It seems to be the same everywhere. I found European mountain ash trees last summer in a forest in New Hampshire; the seed must have been carried over two miles as the crow flies. While this alternation is going on in the East, and may have been going on for thousands of years, the Rocky Mountain district is not so fortunate. When a forest is burned down in that dry region, it is doubtful if coniferous trees will ever grow again, except in some localities specially favored. I have seen localities where short-lived trees were dying out and no others taking their places. Such spots will hereafter take their places above the timber line, which seems to me to be a line governed by circumstances more than by altitude or quality of soil. There are a few exceptions where pines will succeed pines in a burned-down forest. _Pinus Murrayana_ grows up near the timber line in the Rocky Mountains. This tree has persistent cones which adhere to the trees for many years. I have counted the cones of sixteen years on one of these trees, and examined burned forests of this species, where many of the cones had apparently been bedded in the earth as the trees fell. The heat had opened the cones and the seedlings were growing up in myriads; but not a conifer of any other kind could be seen as far as the fire had reached. In the Michigan Peninsula, northern Wisconsin and Minnesota, _P. Banksiana_, a comparatively worthless tree, is replacing the valuable red pine (_P. resinosa_), and in the Sierras _P. Murrayana_ and _P. tuberculata_ are replacing the more valuable species by the same process. In this case, also, the worthless trees are the shortest lived. So we see that nature is doing all that she can to remedy the evil. Man only is reckless, and especially the American man. The Mexican will cut large limbs off his trees for fuel, but will spare the tree. Even the poor Indian, when at the starvation point, stripping the bark from the yellow pine (_P. ponderosa_), for the mucilaginous matter being formed into sap wood, will never take a strip wider than one third the circumference of the tree, so that its growth may not be injured.