Western North America, Southern Alaska to Southern California
"Scouler's willow is an important browse species for domestic livestock and wildlife ungulates, providing critical winter and spring browse. It is often the most preferred browse in ponderosa pine forests for mule deer, white-tailed deer, elk, bighorn sheep, moose, and domestic livestock. Upland sites are heavily used by deer and elk; in riparian areas moose particularly prefer Scouler's willow, especially in winter months. In disturbed areas, Scouler's willow may contribute more moose forage than any other species present. Scouler's willow, occurring in younger stands, is more important in the moose diet than willows present in older stands. Scouler's willow leaves, twigs, and bark are utilized as browse. In British Columbia, it is of moderate to high importance for black-tail deer, is utilized from April through November, and is favored during spring and summer months. Areas of high Scouler's willow cover have been associated with high elk use. In Idaho, it is preferred elk forage, important in both summer and winter months. Elk use tends to be higher in early rather than late summer. In Montana, Scouler's willow is a large part of the regular winter diet for elk as well as a reservoir of surplus feed on which elk depend whenever climatic conditions are of unusual severity. It is also heavily utilized by white-tailed deer and mule deer in Montana and Idaho, predominately as winter forage. In Utah, it provides important summer browse for mule deer. In California, Scouler's willow provides abundant browse of satisfactory quality for domestic livestock and deer. Domestic cattle feed on it in all habitats, while domestic sheep and goats feed on it on drier sites. It has been rated good to fair browse for domestic sheep and goats, fair for deer and domestic cattle, and poor for horses. Small mammals also browse Scouler's willow, and it provides food for grizzly bears.
Upland game birds, ducks, and other birds feed on willow buds, leaves, twigs, and seeds, and Scouler's willow provides nesting and feeding habitat for small birds. Scouler's willow buds provide an important winter food source for grouse, Clark's nutcracker, and the Rocky Mountain jay.
In the early spring, honey bees use willow pollen and nectar as a source of food for brood rearing." 
"Willows are useful for erosion control and windbreaks, and provide medicine for many ailments including indigestion, worms, and stomach complaints. It is the source of "diamond wood", used in carving and furniture making. Scouler's willow was used by Native Americans for traps, snares, sweathouse frames, burden baskets, toys, musical instruments, and medicine." 
"The light colored wood of Scouler's willow offers no striking grain pattern, but its light weight and ability to absorb shocks make it suitable for specialty products like prosthetic devices." 
 Anderson, Michelle D. 2001. Salix scouleriana. In: Fire Effects Information System,. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/tree/salsco/all.html.