DOUGLAS FIR (Pseudotsuga taxifolia).—Though similar in name, this species is not a true fir. Flat leaves, ¾ to 1½ inches long, with a short stem that joins them to the branches. Cones with three-pronged bracts extending beyond the cone scales. Cone scales persistent, the cones falling off the tree whole. Buds are sharp-pointed, shiny, smooth, red brown.
JUNIPERS or CEDARS.—Three species. Fruit reduced to small, bluish berries, needles reduced to tiny green scales on the twigs, though sometimes spreading and about ½ inch long, making twigs very prickly to the touch.
Rocky Mountain red cedar (Juniperus scopulorum).—Berries ¼ to ⅓ inch in diameter, bright blue, usually with 2 seeds. Berries mature in 2 years. Bark scaly, twigs slender and graceful, heartwood red.
One-seed juniper (Juniperus monosperma).—Berries small, mostly less than ¼ inch in diameter, usually contain only one seed, maturing in 1 year. They are covered with a bluish bloom which may be rubbed off exposing the true reddish or coppery color. Twigs stiff and stout. Heartwood brown.
Utah juniper (Juniperus utahensis).—Berries ¼ to ⅓ inch long. Bark ashy gray, about ¼ inch thick, broken into long thin scales. Wood light brown, with nearly white sapwood. Berries are reddish brown, have one or rarely two seeds, mature in 2 years. A small bushy tree, rarely over 20 feet high.
BROADLEAF TREES
Aspen (Populus tremuloides).—Commonly called quaking aspen. Flat, broadly oval leaves, up to 4½ inches across, that tremble characteristically in a breeze. Bark whitish or very pale green, smooth, with black scars where branches have dropped off. Trees rarely more than 60 feet high.
Narrowleaf cottonwood (Populus angustifolia).—Usually a tall tree, 40 to 60 feet high. Bark light yellow-green, divided near the base of old trees into flat ridges; smooth and thinner above. Leaves ¼ to 1 inch wide and 2 or 3 inches long, very similar to willow leaves. Usually found along streams at lower elevations.
Mountain alder (Alnus tenuifolia).—Found along and overhanging streams, usually in clumps, several trees growing from the same root, frequently 4 to 6 inches in diameter and 15 to 25 feet high. Leaves double-toothed, 2 to 4 inches long and 1½ to 2½ inches wide. Mature seed-bearing fruit noticeable in winter.
Willows (Salix, sp.).—The common shrub of creek bottoms. Usually narrow, sharp-pointed leaves. Some willows attain a diameter of 4 inches and a height of 15 to 25 feet. Buds are covered by a single scale.