Saline County has more recorded plant fossil localities than any other
southern Illinois county. Fossil plant collecting localities are
isolated but numerous in the area southwest of Harrisburg. Mine dumps,
such as in the area five or six miles northwest of Eddyville, and many
outcrops are available throughout the region. The fossils probably are
associated with the Murphysboro, Delwood, Willis, Reynoldsburg, and
Battery Rock Coals.
One especially good collecting area is on the south tributary of the
East Branch Cedar Creek about 6½ miles south of Stonefort. The fossils
are found in six feet of shale overlying the Battery Rock Coal horizon.