The Big Buck unit is 5,150 acres to the north and west of the confluence of the Twisp and Methow rivers, the southeast corner about a mile northwest of Twisp. The area is bordered on the west by USFS and DNR land, and on the north, east and south by private land. Although some mule deer winter here, it is primarily used as spring and fall range for deer migrating to and from summer ranges in the Twisp River drainage and the Sawtooth Wilderness. Habitats and vegetation vary from heavily timbered areas (Ponderosa pine and Douglas fir) on the north facing aspects, to open shrub steppe (bitterbrush, sagebrush, and bunch grasses) on the south and east facing slopes. Riparian vegetation dominates around lakes, ponds and streams. Key habitat for biodiversity includes Deadhorse, Shaw and Aspen lakes and Peters Puddles.