It also contains the headwaters of numerous streams, including Pine, Indian, Strawberry, Canyon, Bear, Lake, Wall, Roberts, and Big Creek.

The sequence is distinctive from other Permo-Triassic ophiolite-type complexes in Western North America by its large volume of silicic intrusive and volcanic rocks.

Extensive Tertiary-age continental volcanic flows covered the region, and subsequent uplift and erosion has exposed the older basement.

Common flowers in the Wilderness include buttercups, mariposa lily, shooting star, paintbrush, wild onion, yarrow, and western Jacob's ladder.

Other abundant vegetation includes wild strawberry, grouseberry, thinleaf huckleberry, Oregon grape, swamp gooseberry, thimbleberry, and Sitka alder.