View photos of the edible plant Acer negundo (Box elder), profiled in the Wild Edible Series: Colorado and Utah.

A passage from Wild Edible Plants of Colorado:

In Colorado, this medium–sized tree is not found in the high mountains (Aspen–Fir–Spruce belt), but rather in the lower ranges and foothills. It’s intermingled with Cottonwood, Currant, Lemonade berry, and other scrub vegetation.

A passage from Wild Edible Plants of Utah:

There are no significant medicinal uses or cautions for the tree. Box elder is actually a species of Maple (Acer), not Elder (Sambucus) or Ash (Fraxinus). Its parted leaves vaguely resemble an Elder or Ash leaf, hence the common name discombobulation. Other species of Maple (Rocky Mountain maple and Big–tooth maple in Utah) are utilized the same as Box elder.