Future Tense Trees: is situated in southern Leelanau County, Michigan at the base of the peninsula forming the western shore of the Grand Traverse Bay. While generally a number of counties north of the Tension Zone, this location is the nexus for the southerly and northerly distribution of a number of tree species associated with the Tension Zone given the climatic effects of Lake Michigan’s mitigating winter low temperatures.

The county record maps for the two species presented here well represent that phenomena. County range maps depict the counties from which herbarium specimens (pressed and dried plants) have been collected. While the absence of a county record does not prove that the species does not occur in that county, this tends to be a relatively accurate account of species distribution used by states and aggregated in USDA range maps.