NATIONAL PARK SERVICE Forests of Yosemite, Sequoia, and General Grant National Parks

INCENSE CEDAR (LIBOCEDRUS DECURRENS).

The incense cedar (fig. 11), like the other so-called cedars of the United States, is not a true cedar at all, although it is closely allied to the true cedars. Like most of those trees in this country, the incense cedar has scale-like leaves. It is a beautiful tree, with tapering, conical trunk and broadly pyramidal crown until old age, when its limbs are often reduced to a stubby cluster of two or three at the very top of the tree. The bark in youth is a deep red under a smooth, transparent gray surface film. On old trunks it is a reddish to grayish brown, thick, and smoothly and heavily ridged. The foliage is arranged in flat, fanlike sprays.

FIG. 11.——Incense cedar (Libocedrus decurrens).

The incense cedar has a very restricted range, being, like the sugar pine, practically confined to the State of California. It revels in moist gulches, stream bottoms, and flats, but, like the yellow pine, it can also push its conquests out on to the dry ridges. Except in youth, it does not often grow in pure stands, the mature trees being scattered thinly through the forest. It is a prolific seeder, bearing abundantly every two or three years or oftener. The seedlings are more adaptable than those of almost any other species to varied conditions of moisture, soil, and light, and spring up often in great numbers.

In the middle Sierras mature trees are from 30 to 40 inches in diameter. Many veterans may be found from 4 to 5 feet in diameter, and occasionally one as large as 6 feet. On account of the tapering trunks, the height for a given diameter is much smaller than it is in the pines. Growth is often rapid in youth, but slows down much more rapidly than it does in the pines. Under average conditions, in the region of the Yosemite, a tree 12 inches in diameter is about 55 feet tall and from 80 to 100 years old; at 30 inches in diameter it is about 115 feet tall and 450 years old; while at 60 inches it is 145 feet tall. On very good or very poor sites the heights given will be increased or decreased by from 30 to 40 feet for the larger diameters.

Incense cedar is not seriously injured by insects. Its worst enemy is a fungus disease which produces a dry rot in the interior. This is so serious as to prevent the use of the wood for many finer purposes for which it would otherwise be fitted. Cedar is also badly damaged by fire, for, although the bark is thick, it is much more inflammable than is that of the pines.

Incense cedar in the past has been very little used for anything but fence posts and rails, for which its great durability adapts it. It is now being used successfully for piling on the Pacific coast, where ship worms attack badly such timbers made from most other woods. On account of its softness, evenness of grain and fineness of texture it has recently been successfully tried for lead-pencil making, in which perfect wood in short lengths can be used, and it seems likely to replace for this purpose the waning supply of the red cedar of the East.