Plant Guide

Douglas Fir (Pseudotsuga menziesii)

Bark

On younger specimens the bark is gray and smooth. Older specimens have a thick, corky bark that is often dark chocolate-brown in color. For older trees, the thick bark serves as a protective layer that can save the tree from being damaged in a forest fire.

Foliage

Douglas fir is distinguished by its thin, flat, one inch-long evergreen needles that are pointed but soft to the touch. . They produce light brown cones that have distinctive three-pronged bracts or "tails" extending from between the scales. Unlike true fir trees, the cones hang down from the branches rather than standing upright.

Size

Commonly grow up to 250 feet tall and 5-6 feet in diameter, and can live for over 500 years. Truly large old growth Douglas firs have been reported to reach over 300 feet in height and 10 ft in diameter, making them among the largest trees in the world. The Douglas fir is the most abundant tree in the Arboretum as well as the most economically valuable timber tree in North America.

Western Hemlock (Tsuga heterophylla)

Bark

Dark brown to reddish-brown bark, with a rough texture and relatively shallow vertical furrows.

Foliage

Western hemlock is distinguished by its flat, blunt-tipped emerald-green needles. The needles come in two lengths with the shorter ones standing erect on the top of the twig, giving hemlock branches a noticeably furry appearance. The cones are small, less than an inch in length, and hang down from the ends of the branches.

Size

Western hemlock typically grows to about 98 to 164 feet in height and to about 4 feet in width. Western hemlock is a very shade-tolerant tree and prefers to germinate and grow in the understory of its taller neighbors. The best trick to identifying a western hemlock tree is to look at the growing tip (or leader) of the tree, which is usually drooping rather than erect like in most other conifers.

Western Red Cedar (Thuja plicata)

Bark

Brownish-red stringy bark with very shallow vertical furrows, appearing grayish-red in some cases.

Foliage

Sharp pointed scale-like leaves with a mossy green hue that overlap like shingles. They are organized in flat sequences. The branches droop down but turn up noticeably at the ends. Numerous small cones grow in a bent back position along the branch.

Size

The largest of all cedar species, Western red cedar grows up to 150 to 200 feet tall. Labeled the broadest tree in the Northwest, its buttressed base spans from 2 to 8 feet in diameter, with some old-growth specimens surpassing 15 to 20 feet diameter at ground level. In ideal locations individual Western red cedars can live over 1,000 years.

Tall Oregon Grape (Mahonia aquifolium)

One of the most prominent traits of Tall Oregon Grape is the superficial similarity of its leaf to that of a Holly tree. The leaves of both plants have a shiny surface, a leathery texture, and a spiny edge. The difference is that Oregon grape actually has a compound leaf, and what appear to be individual leaves are leaflets--with five to nine of them making up each actual leaf. Tall Oregon Grape grows approximately five to six feet in height. Small clusters of yellow flowers appear before the edible blue berries.

Indian Plum/Osoberry (Oemleria cerasiformis)

Indian Plum is a large native shrub that can grow up to thirteen feet tall. The leaves are shaped like a knife blade and are two to five inches long. If the leaves are damaged, they smell like cucumbers. The five-petaled waxy blossoms droop in white clusters. The flowers turn into a bitter but edible plum-like fruit.

Snowberry (Symphoricarpos albus)

Snowberry is a medium sized shrub and is distinguishable by its oval-shaped leaves arranged as opposite pairs along a round stem. Its creamy or pinkish tubular flowers precede the inedible white berries in the fall.