Identifying trees is a lot like identifying people. You can easily recognize a close friend, even from a fast-moving car or from a picture when the friend had a different physical appearance. However, in a room full of strangers, you need to concentrate on individual characteristics before you can begin to tell one person from another.
It’s the same with trees. When you know a tree well, you’ll be able to name it whether you see its leaves, fruit, flowers, or even its shape and color. When you know it well enough, you’ll be able to recognize it in different stages of growth, in different locations, and even from fast-moving cars!
To get to know trees that well, you first learn to identify their leaves, flowers, and fruit. Then, as the tree becomes more familiar, examine its bark, branching pattern, color, and shape. Eventually, you may even get to know many trees by where they live.
We Oregonians are fortunate to have a wide diversity of native tree species growing in our state. Our state’s combination of soils, climate, and topography – expressed across a continuum from the Pacific coast to the high Cascades to the arid interior – gives us nearly 30 species of conifers (also known as evergreens – retaining their leaves year-round) and 37 species of broadleaf trees (also referred to as deciduous – losing their leaves in the winter).
Conifers grow especially well on the west slopes of the Cascades and throughout the Coast Range, where relatively warm temperatures and abundant rainfall allow them to grow even in winter. Conifers also grow well on the east side of the Cascades because their small leaves with thick, waxy coatings help the trees retain moisture during the hot, dry summers and cold, dry winters. Furthermore, conifers grow well at high elevations because their evergreen nature allows them to begin growing in the spring as soon as temperatures rise above freezing.
Oregon’s conifers can be broken into two major groupings based on their leaf type: needle-like or scale-like. Those with needle-like leaves include Douglas-fir, pines, true fir, spruce, larch, hemlock, redwood, and yew. Conifers with scale-like leaves include the various cedars and juniper.
Broadleaved trees are often specialists in our forests. In some cases, they’re early successional species, occupying areas of recent disturbance by floods, avalanches, or windthrow. In other cases, they’re especially adapted to hot, dry conditions, particularly where soils are shallow with little moisture-holding capacity. In still other cases, they’re able to tolerate wet soils during the growing season, an especially valuable adaptation in the large valleys of western Oregon.
Useful Links for Tree ID:
- Oregon State University’s “Common Trees of the Pacific Northwest”
- Oregon Forest Resources Institute’s “Trees of Oregon’s Forests
Much of the text above was adapted from “Trees to Know in Oregon,” Oregon State University Extension Service publication EC 1450, April 2005.