OSU trail maps can be found on their recreation web page, and their most recent map is here (as of April 2014).

The summer of 2014 will see many logging/thinning operations in McDonald Forest.

Popular trails in the forest are Dan’s Trail, Horse Trail (upper and lower), Extendo and Uproute, and a number of trails in the Peavy Arboretum area.  Climbing up to McCulloch Peak is also popular.

The main entrances to the forest are at Oak Creek, some trails in the Timberhill neighborhood of Corvallis, Chip Ross, Lewisburg Saddle, and Soap Creek (on Sulphur Springs Rd).