Six Mile Creek marks the western boundary of the preserve. Two tributaries, lesser intermittent streams, and small springs flow across the property. Geological features along the creek include exposed shales and sandstones, with especially good examples of joint-plane fracturing. Upper reaches of the tributaries cross glacial rubble and alluvial material. The upper section of Six Mile Creek is an important site for the study of aquatic insects. The steep gorge walls are covered with ferns, lichens, and liverworts.
The Slaterville 600 has always been forested, and much of the site is old-growth forest (trees older than 150 years). It is part of a much larger forested area that includes the Hammond Hill State Forest. As in much of the rest of the state, these lands were extensively cut in the late 1800s; however, there is no evidence of farm use in the natural area. Mature forest covers the tract.
The site includes steep, west-facing hillsides and a high hilltop. The elevation ranges from 1,200 feet at Six Mile Creek to 1,650 feet at the top of the slope. Maple and beech are dominant throughout the forest. Hemlock and yellow birch are common on the steep slopes along the creek. Large white ash is common on the upper slopes. The hilltop forest is dominated by red maple, oaks, and beech. Maple-leaved viburnum (Viburnum acerifolium), witch hazel (Hamamelis virginiana), and striped maple (Acer pensylvanicum) are common in the understory. The site is noted for the abundance of wildflowers along the creek beds in the rich, well-drained, gravelly soils.
The Williams Preserve is surrounded by the Hammond Hill State Forest. The area has a wilderness character and is used for recreation, including hunting, hiking, cross-country skiing, and environmental education.
Norris, W. Glenn. 1951. The Origin of Place Names in Tompkins County. Ithaca, N.Y.: DeWitt Historical Society of Tompkins County.