Three upland woodlots in southeastern Wisconsin, originally sampled by the Plant Ecology Lab of UW-Madison in 1949, were resampled in 1981. In general, red and white oaks were being replaced by more shade-tolerant species. Two of the sites, Zirbe's Woods and Petrifying Springs Woods, appear headed for complete domination by sugar maple. Thompson Woods, where maple was absent, was at an earlier successional stage. In Thompson Woods, basswood and white ash were becoming dominant.
Leitner, L.A. 1987. Three decades of change in three Southeastern Wisconsin woodlots. 20(2): 1-12.