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The silvery luster of the needles of this tree gives it the name silver pine, by which many people know it. It appears in literature as mountain Weymouth pine, the reference being to the eastern white pine (Pinus strobus), which is sometimes called Weymouth pine. Finger-cone pine is a California name; so are mountain pine and soft pine. In the same state it is called little sugar pine, to distinguish it from sugar pine (Pinus lambertiana), which it resembles in some particulars but not in all. It is thus seen that California is generous in bestowing names on this tree, notwithstanding it is not abundant in any part of that state and is unknown in most parts.

The botanical name means “mountain pine,” and that describes the species. It does best among the mountains, and it ranges from an altitude of from 4,000 feet to 10,000 on the Sierra Nevada mountains. Sometimes trees of very large size are found near the upper limits of its range, but the best stands are in valleys and on slopes at lower altitudes. Its range lies in British Columbia, Montana, Idaho, Washington, Oregon, and California. In the latter state it follows the Sierra Nevada mountains southward to the San Joaquin river.

This species has been compared with the white pine of the East oftener than with any other species. The weights of the two woods are nearly the same, and both are light. Their fuel values are about the same. The strength of the eastern tree is a little higher, but the western species is stiffer. The woods of both are light in color, but that of the eastern tree is whiter; both are soft, but again the advantage is with the eastern tree. The western pine generally grows rapidly and the annual rings are wide; but, like most other species, it varies in its rate of growth, and trunks are found with narrow rings. The summerwood is thin, not conspicuous, and slightly resinous. The small resin passages are numerous. The heartwood is fairly durable in contact with the soil.

The western white pine has entered many markets in recent years, but it is difficult to determine what the annual cut is. Statistics often include this species and the western yellow pine under one name, or at least confuse one with the other, and there is no way to determine exactly how much of the sawmill output belongs to each. The bulk of merchantable western white pine lumber is cut in Idaho and Montana. The stands are seldom pure, but this species frequently predominates over its associates. When pure forests are found, the yield is sometimes very high, as much as 130,000 feet of logs growing on a single acre. That quantity is not often equalled by any other forest tree, though redwood and Douglas fir sometimes go considerably above it.

The western white pine’s needles grow in clusters of five and are from one and a half to four inches long. The cones are from ten to eighteen inches long. The seeds ripen the second year. Reproduction is vigorous and the forest stands are holding their own. Trees about one hundred and seventy-five feet high and eight feet in diameter are met with, but the average size is one hundred feet high and from two to three feet in diameter, or about the size of eastern white pine.

The wood is useful and has been giving service since the settlement of the country began, fifty or more years ago. Choice trunks were split for shakes or shingles, but the wood is inferior in splitting qualities to either eastern white pine or California sugar pine, because of more knots. The western white pine does not prime itself early or well. Dead limbs adhere to the trunk long after the sugar pine would shed them. In split products, the western white pine’s principal rival has been the western red cedar. The pine has been much employed for mine timbers in the region where it is abundant. Miners generally take the most convenient wood for props, stulls, and lagging. A little higher use for pine is found among the mines, where is it made into tanks, flumes, sluice boxes, water pipes, riffle blocks, rockers, and guides for stamp mills. However, the total quantity used by miners is comparatively small. Much more goes to ranches for fences and buildings. It is serviceable, and is shipped outside the immediate region of production and is marketed in the plains states east of the Rocky Mountains, where it is excellent fence material.

A larger market is found in manufacturing centers farther east. Western white pine is shipped to Chicago where it is manufactured into doors, sash, and interior finish, in competition with all other woods in that market. It is said to be of frequent occurrence that the very pine which is shipped in its rough form out of the Rocky Mountain region goes back finished as doors and sash. When the mountain regions shall have better manufacturing facilities, this will not occur. In the manufacture of window and hothouse sash, glass is more important than wood, although each is useless without the other. The principal glass factories are in the East, and it is sometimes desirable to ship the wood to the glass factory, have the sash made there, and the glazing done; and the finished sash, ready for use, may go back to the source of the timber.

The same operation is sometimes repeated for doors; but in recent years the mountain region where this pine grows has been supplied with factories and there is now less shipping of raw material out and of finished products back than formerly. The development of the fruit industry in the elevated valleys of Idaho, Montana, Washington, and Oregon has called for shipping boxes in large numbers, and western white pine has been found an ideal wood for that use. It is light in weight and in color, strong enough to satisfy all ordinary requirements, and cheap enough to bring it within reach of orchardists. It meets with lively competition from a number of other woods which grow abundantly in the region, but it holds its ground and takes its share of the business.

Estimates of the total stand of western white pine among its native mountains have not been published, but the quantity is known to be large. It is a difficult species to estimate because it is scattered widely, large, pure stands being scarce. Some large mills make a specialty of sawing this species. The annual output is believed to reach 150,000,000 feet, most of which is in Idaho and Montana.

Mexican White Pine (Pinus strobiformis) is not sufficiently abundant to be of much importance in the United States. The best of it is south of the international boundary in Mexico, but the species extends into New Mexico and Arizona where it is most abundant at altitudes of from 6,000 to 8,000 feet. The growth is generally scattering, and the trunks are often deformed through fire injury, and are inclined to be limby and of poor form. The best trees are from eighty to one hundred feet high, and two in diameter; but many are scarcely half that size. The lumbermen of the region, who cut Mexican white pine, are inclined to place low value on it, not because the wood is of poor quality, but because it is scarce. It is generally sent to market with western yellow pine. Excellent grades and quality of this wood are shipped into the United States from Mexico, but not in large amounts. An occasional carload reaches door and sash factories in Texas, and woodworkers as far east as Michigan are acquainted with it, through trials and experiments which they have made. It is highly recommended by those who have tried it. Some consider it as soft, as easy to work, and as free from warping and checking as the eastern white pine. In Arizona and New Mexico the tree is known as ayacahuite pine, white pine, and Arizona white pine. The wood is moderately light, fairly strong, rather stiff, of slow growth, and the bands of summerwood are comparatively broad. The resin passages are few and large. The wood is light red, the sapwood whiter. The leaves occur in clusters of five, are three or four inches long, and fall during the third and fourth years. The seeds are large and have small wings which cannot carry them far from the parent tree.

Pinon (Pinus edulis). This is one of the nut pines abounding among the western mountains, and it is called pinon in Texas, nut pine in Texas and Colorado, pinon pine and New Mexican pinon in other parts of its range, extending from Colorado through New Mexico to western Texas. It has two and three leaves to the cluster. They begin to fall the third year and continue through six or seven years following. The cones are quite small, the largest not exceeding one and one-half inches in length. Trees are from thirty to forty feet high, and large trunks may be two and one-half feet in diameter. The tree runs up mountain sides to altitudes of 8,000 or 9,000 feet. It exists in rather large bodies, but is not an important timber tree, because the trunks are short and are generally of poor form. It often branches near the ground and assumes the appearance of a large shrub. Ties of pinon have been used with various results. Some have proved satisfactory, others have proved weak by breaking, and the ties occasionally split when spikes are driven. The wood’s service as posts varies also. Some posts will last only three or four years, while others remain sound a long time. The difference in lasting properties is due to the difference in resinous contents of the wood. Few softwoods rank above it in fuel value, and much is cut in some localities. Large areas have been totally stripped for fuel. Charcoal for local smithies is burned from this pine. The wood is widely used for ranch purposes, but not in large quantities. The edible nuts are sought by birds, rodents, and Indians. Some stores keep the nuts for sale. The tree is handicapped in its effort at reproduction by weight, and the small wing power of the seeds. They fall near the base of the parent tree, and most of them are speedily devoured.