An excerpt from the book "Wild in the City - Exploring The Intertwine."
Essentially untouched from the 1930s to 2000, the canyon has been the force of an ambitious habitat restoration project for the past decade. This work has restored the canyon to its "natural" state while improving opportunities for visitors to appreciate its beauty.
The Canyon was formed by a number of springs located in the eastern portion of the lake, which constitute the headwaters of Crystal Springs Creek. The springs form a shallow lake that feeds into a fish ladder, and then descends to become a swift-flowing creek that slows through a meadow, passes under a new bridge at SE 28th Avenue, and reaches the Crystal Springs Rhododendron Garden located just to the south. Eventually, this water will enter the Willamette River before finding the pacific ocean via the Columbia. Pacific lamprey in the lake and returning salmon prove that there is uninterrupted passage between the headwaters and the ocean.
The canyon was donated to Reed College in 1910. At the time, the college intended to develop its real estate holdings along traditional lines — Tudor Gothic buildings, sculpted grounds, and formal gardens. Prohibitive costs, however, led the trustees in a different direction. The result is that the canyon was never developed nor manicured, and in 1913 it was declared a wildlife refuge by the state of Oregon. it still holds that status today.
The most widely used stretch of the canyon is the upper lake loop, which takes visitors on a gentle walk along maintained trails that are only occasionally interrupted by swampy vestiges of the springs underfoot. Side trails may lead you out of the canyon and onto the college grounds, but for the most part the trail is easy to navigate.
Douglas fir, big-leaf maple, red alder, and western redcedar form the tree canopy, while shrubs such as red elderberry, oregon grape, and black hawthorn, along with herbs including trillium, pacific water parsley, hardtack, skunk cabbage, and stinging nettle are common in the understory. Wildflowers abound in spring (over fifty different species have been identified in the canyon). Among the more common ferns are sword and bracken. Also, look in the drier areas for the somewhat uncommon goldback fern.
More than eighty bird species, including great blue heron and green herons, belted kingfishers, and seven different species of warbler have been sighted in the canyon. This is also a good place to call for western screech-owls. Cooper's hawks are frequent guests, swooping low overhead, scouting for prey. In recent years, bald eagles have perched in trees overlooking the canyon.
In addition to birds, the canyon is home to a diverse array of other wildlife. Fallen trees lining the lake show the telltale marks of resident beavers. Coyotes are occasionally glimpsed, furtively making their way through tall grass at the lake's edge. River otter and muskrat have also been sighted in the canyon. The damp underbrush of the southeast side of the canyon is home to the terrestrial Ensatina salamander. Nesting ducks guide their young across the lake. Mallards are obvious, but wood ducks, American wigeons, buffleheads, lesser scaup, common mergansers, green-winged teals, and ruddy ducks are here as well. In the winter look for hooded mergansers.