An Ecological History of the Great Lakes Forest of Michigan

(1) The historical development, i.e. changing species composition and the areal extent, of the vegetation of the High Plains region of Michigan is traced with the use of printed and manuscript materials and contemporary forest survey records. (2) The classic pre-settlement Great Lakes pine forest occupied the rolling upland areas and was conditioned to fires at 130-260 year intervals. Fires were much more frequent on the drier outwash sands of the jack pine plains and openings and almost non-existent on the moist hemlock-white pine-northern hardwoods forests of the uplands and the swamp conifer forests of the lowlands (3) Selective logging of the white pine and later the hemlock and the better hardwoods converted the hemlock-white pine-northern hardwoods type to sugar maple. Waves of fires, following the logging in rapid succession, upset the natural equilibrium of the Great Lakes forest. The ignition of the remaining debris or the slash destroyed the remaining seed trees and the seedling pine in the mixed pine type. The result was a poorly stocked forest of oak sprouts and aspen suckers. Oak and aspen had formerly played a relatively subordinate role in the pre-settlement forest. (4) The cessation of fires in 1920-40 allowed the maturation of the oak, the aspen, and the jack pine and set the stage for the new pulp-oriented industrial forest of the 1950s.