It must not be confounded with the red silver fir (Abies Magnifica) so eloquently described as the chief delight of the Yosemite region by Smeaton Chase.  It grows from seventy to two hundred and fifty or possibly three hundred and fifty feet high, and is the most important lumber tree of the country, considering the quality of its timber, the size and length of its logs, and the great amount of heavy wood and freedom from knots, shakes or defects.  On young trees the bark is smooth, gray or mottled, sometimes alder-like; on old trunks one to six and a half inches thick, soft or putty-like, dark brown, fissured into broad heavy furrows.  The young rapid growth in the open woods produces “red fir”, the older slower growth in denser woods is “yellow fir”.  Every tree to a greater or lesser extent exhibits successively these two phases, which are dependent upon situation and exposure.

The chief difference between the white and red fir is in the spiculae or leaves.  Those of the red fir are shorter, stubbier and stiffer than those of the white.  The bark, however, is pretty nearly alike in young trees and shows a marked difference when they get to be forty to fifty years old.

The Alpine Spruce (Hesperopeuce Pattoniana Lemmon) is found only in the highest elevations.  Common in Alaska it is limited in the Tahoe region to the upper points of forests that creep up along glacier beds and volcanic ravines, close to perpetual ice.  It disappears at 10,000 feet altitude on Mt.  Whitney and is found nowhere south of this point.  On Tallac, Mt.  Rose and all the higher peaks of the Tahoe region it is common, giving constant delight with its slender shaft, eighty to a hundred feet high, and with a diameter at its base of from six to twelve feet.  It is only in the lower portions of the belt where it occurs.  Higher it is reduced to low conical masses of foliage or prostrate creeping shrubs.

By many it is regarded as a hemlock, but it is not strictly so.  It was first discovered in 1852 by John Jeffrey, who followed David Douglas in his explorations of the forests of the American Northwest.

In favorable situations, the lower limbs are retained and become long, out-reaching, and spreading over the mountain slope for many feet; the upper limbs are irregularly disposed, not whorled; they strike downward from the start (so that it is almost impossible to climb one of the trees for want of foothold), then curving outward to the outline of the tree, they are terminated by short, hairy branchlets that decline gracefully, and are decorated with pendant cones which are glaucous purple until maturity, then leather brown, with reflexed scales.

The main stem sends out strong ascending shoots, the leading one terminating so slenderly as to bend from side to side with its many purple pendants before the wind, and shimmering in the sunlight with rare beauty.—­Lemmon.

On the slopes of Mt.  Rose near timber line, which ranges from 9700 to 10,000 feet according to exposures, while still a tree of considerable size, it loses its symmetrical appearance.  Professor Kennedy says: