However, the exhaustion of no species of the elms in this country need be expected soon. The most apparent peril lies ahead of cork elm, because it never was abundant, and demand, which has been large for a long time, is still strong. The species is scattered over more than 200,000 square miles, and a long time must elapse before the last cork elm finds its way to the sawmill. The situation of white elm is more promising. It may be among the last trees of the American forests to take its final departure. Its wide range and its bounteous seed crops insure a supply, though not necessarily a large one, for a long time. The greatest peril to elms, as well as to many other forest trees, is that, when weakened by depletion, some disease will attack them and destroy the remnants. Experience in New England and elsewhere has shown that elm has no great resisting power when a strong attack is made upon it. [Illustration] SLIPPERY ELM [Illustration: SLIPPERY ELM] SLIPPERY ELM (_Ulmus Pubescens_) This tree is known as slippery elm in every state where it grows, thirty or more; but in some localities it has other names also. It is doubtful if any person who is acquainted with the tree would fail to recognize it by the name slippery elm, though some who are acquainted with the lumber only might not know it by that name. Those who call it red elm have in mind the color of the heartwood which is of deeper red than the wood of any other elm, or they may refer to the tawny pubescence on the young shoots in winter. The botanical name describes that characteristic. In the North, the slippery elm is sometimes known as moose elm. It furnishes forage in winter for the moose and other herbivorous animals when ground plants are covered with snow. The moose is able to eat branches as thick as a man’s thumb. The principal food element in the twigs is the mucilaginous inner bark. It is this which gives the tree its name slippery elm. The value of the bark as a food has been questioned. It is agreeable to the taste of both man and beast, but it is claimed that a human being will starve to death on it, though it will prolong life several days. The lower animals, however, seem able to derive more benefit from eating the bark. An incident of the War of 1812 appears to prove this. The army under General Harrison, operating in the vicinity of Lake Erie, kept the horses of the expedition alive by feeding them on slippery elm bark, stripped from the trees and chopped in small bits.