Spence Field is a grassy bald, a type of meadow found in higher elevations in the Appalachian Mountains. Grassy balds are characterized by thick grass and relatively sparse tree coverage. In the late 19th and early 20th centuries, Spence Field was roughly at the center of a pasture that stretched across the crest of the Western Smokies from Gregory Bald in the west all the way to Silers Bald to the east. Since the establishment of the Great Smoky Mountains National Park in the 1930s, however, wooded plants have started reclaiming much of this stretch, including Spence. The park service currently maintains the grassy balds atop Gregory Bald and Andrews Bald, while allowing the others to return to their natural state.