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The Cone-bearing Trees of Yosemite (1939) by James E. Cole


DOUGLAS FIR

Pseudotsuga taxifolia (Poir.) Britt.

Douglas Fir, Pseudotsuga taxifolia
[click to enlarge]
When outlined against the mists of waterfalls, the ever waving plumes of Douglas Fir foliage are gracefully attractive in contrast to they more rigid posture of other conifers. The supple sprays, pendulous from spreading branches and instantly responsive to fire slightest wind, are singularly characteristic of these trees. Their identity is proclaimed by a host of slender drooping branchlets. In their favorite haunts beside the waterfalls, Douglas Firs have halted their southern conquest after a steady southward march from British Columbia apparently satisfied that no more glorious abode remains to be occupied. These magnificent trees from the northwest are somewhat of a botanical puzzle as indicated by their twenty-eight common names. Known to the woodsmen as Red Fir, or Yellow Fir, sold for lumber as Oregon Pine, called Douglas Spruce by many and False Hemlock by others, yet they are neither firs, pines, spruces nor hemlocks but represent a distinct and peculiar species. Botanically they are closely related to the firs, hemlocks and spruces, probably most closely to the latter, but differ sufficiently from each to be classified in a separate genus. The scientific name, Pseudotsuga taxifolia, when separated into its component parts indicates this confused relationship — pseudotsuga (False Hemlock) taxifolia (with foliage like the Yew trees). The common name of Douglas Fir honors David Douglas, the discoverer, and directs attention to the fir-like character of the bark by which woodsmen recognize trees.

The leaves bear an apparent resemblance to the true firs. They are attached singly to the branchlets, but have short petioles (leaf stems) and grow all around the twigs in spirals which tend to be flat on horizontal branches somewhat like those of White or Red Firs but on drooping branches are evenly spaced giving a full rounded aspect. The needles are short, between three-fourths and one and one-half inches in length, flat, glossy, light-green above and gray-green beneath. In the late spring the tufts of new leaves like those of the true firs are a vivid yellow-green which contrasts so strikingly with the older, darker foliage as to suggest clusters of flowers. The conical reddish-brown bud scales from which the new foliage grows remain on the twigs for at least a year as brown, papery scales and thus serve as additional identification marks.

Like the two true firs in Yosemite, the bark of young Douglas Firs contains balsam blisters, is whitish or ashy and smooth, but soon becomes rough and dark gray. On old trunks the broad faces of the ridges are dark brown whereas the sides of the deep fissures have an ashy sheen difficult to describe. The inner bark in section consists of alternate layers of tan and red thus combining the inner bark colors of both White and Red Firs.

The cones are signally different from those of all other Yosemite conifers in possessing trident-shaped bracts that extend beyond the cone scales. In fact, this three lobed bract alone is sufficient to distinguish the Douglas Fir from all other North American trees except its near relative, the Bigcone Spruce (Pseudotsuga macrocarpa) of Southern California. The reddish-brown cones hang from the branches and fall entire in contrast to the true firs in which the cone scales fall one by one. The cones frequently remain on the trees for a year after ripening.

Douglas Fir is one of the most important timber trees in the world. From no other conifer is wood produced so strong, flexible and durable. From no other tree is so much lumber cut. In Washington and Oregon where it attains its maximum development, thousands of Douglas Firs are over 200 feet high while many have been found 300 feet in height. The tallest recorded Douglas Fir towers 330 feet. It is just thirty-four feet shorter than the “Founder’s Tree” the tallest tree in the world, a Coast Redwood, and exactly equals in stature Yosemite’s tallest tree, a Giant Sequoia in the Merced Grove.

Since these trees have come to Yosemite from the north, they are to be looked for in the cooler portions of the park. Yet, unlike other northern species, they do not climb to high elevations for colder habitations. Their vertical range is between 3500 and 5500 feet, and, consequently, Douglas Firs are restricted to the shady sides of the deep canyons or near waterfalls. Visitors in Yosemite Valley who enjoy watching the streams as they pour over the perpendicular cliffs frequently see the leaping water comets of the falls framed in the swaying sprays of this graceful. tree.



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