The park and environs were still rural when the park was established; further, most of the park is in a steep little canyon, so the park was spared all but minimal rural development as well as the surrounding boom of urban development. The full old growth forest (1,000–2,000 years old) was all clearcut relatively early (around the early 20th century); the predominantly maple-alder successional stage forest is today mature. Evergreens will gradually predominate. Typical trees include deciduous maple, alder, ash, and willow, with madrona, cascere, and evergreen Western Red Cedar, Western Hemlock, Douglas fir, pine, and spruce. Sedges, cattails, and other common indigenous flora fill out the understory and wetland areas, with particularly huge Lady Ferns along the ravine between 105th and 110th streets.