This Wilderness is located north and west of Waldo Lake. Waldo Lake is high on the western slopes of the Cascades north of Willemette Pass on Oregon State Highway 58, the lake is located at an elevation of 5,414 feet. The area around Moolack Mt, in the northern part is trailless. The Waldo Lake Wilderness is generally high elevation ranging from the Waldo Lake elevation of 5414 feet to the 7002 foot Mt. Ray in the southeast corner of the Wilderness. The environment supports a variety of tree species and flora.
Mountain hemlock dominates the higher elevations with an understory of red and blue huckleberries.
Lower elevations are characterized by stands of Douglas-fir, western redcedar, and western hemlock with predominant understory of vine maple. In early summer the area comes alive with brilliantly colored wildflowers. Lupine, heather, larkspur, columbine, elephant head, shooting star, and penstemon border lakeshores, streams, and meadows.