Coast Douglas-fir

The coast Douglas-fir is a giant evergreen tree, and it has a secret: it is not really a fir at all. Its scientific name means false hemlock. You can spot one by looking at its hanging cones. Each cone scale has a tiny three-pointed flap that looks like the back half of a mouse, with two little feet and a tail poking out. Once you see the mouse, you never forget it.

The coast Douglas-fir is one of the tallest trees on Earth, but its name is a bit of a trick. It is not a true fir at all. Scientists put it in a group called Pseudotsuga, which means false hemlock. The tree was named for David Douglas, a Scottish botanist, after another naturalist, Archibald Menzies, first recorded it on Vancouver Island in 1791. The easiest way to identify one is its cones. Each scale has a long, three-pointed papery flap, called a bract, that sticks out and looks like the back half of a mouse diving into the cone, two feet and a tail showing.

Coast Douglas-firs grow all along the Pacific coast, from British Columbia in the north down to central California. That includes the rainy Olympic Peninsula in Washington, where the Hoh Rain Forest sits. These trees like well-drained soil and can grow from the beach all the way up to about 4,900 feet on the mountains. In an old forest, they are often the tallest trees of all, towering over everything else around you.

This tree ranges along the Pacific coast from west-central British Columbia south to central California, which puts the Olympic Peninsula and the Hoh Rain Forest area squarely in its home. Coast Douglas-firs grow from sea level near the ocean up to elevations of about 1,500 meters (4,900 feet) or higher, and they prefer well-drained soils. In old-growth forests like those in Olympic National Park, Douglas-firs are usually the giants of the canopy, the trees that rise highest and live longest. Mature trees commonly reach 250 feet or more, so standing beneath one means craning your neck to find the top.

A Douglas-fir feeds a lot of hungry animals. Mice, voles, shrews, and chipmunks eat huge amounts of its seeds. In one Oregon study, small mammals ate about 65 percent of a whole seed crop. Birds like crossbills and pine siskins eat the seeds too. When old trees die and stand as snags (dead, hollow trees), woodpeckers and other birds nest inside them. So one tree can help feed and house many forest neighbors.

The coast Douglas-fir is a key player in the rainforest food web. Its seeds are a feast for small mammals, mice, voles, shrews, and chipmunks ate an estimated 65 percent of one seed crop in an Oregon study, and birds such as crossbills, pine siskins, and sparrows eat them as well. Young seedlings give deer something to browse in spring. The tree also keeps working after it dies. Snags, the standing dead trunks of old Douglas-firs, are common in forests older than 110 years and become apartment buildings for cavity-nesting birds. Old-growth Douglas-fir forest is also the main home of the red tree vole and the northern spotted owl. Without these giants, the animals that depend on their seeds, branches, and hollow trunks would lose their food and shelter.