Anoka Ecosystems:
Hardwood Swamp
Hardwood swamps are forested wetlands, but unlike a lowland hardwood forest, hardwood swamps exist in saturated peat soils and muck. This community exists in Anoka County on old lake bottoms and floodplains. Since hardwood swamp sites are very wet they are often left untouched from disturbance. This allows some stands to reach "old-growth" stage and provides conditions favorable for extremely rare plant species, such as the halberd leaved tearthumb and the yellow bartonia.
Common tree species in this ecosystem are black ash, poison sumac, yellow birches, red maples, American elms, green ashes, quaking aspens and may include tamaracks. Of these, the most dominant are black ash, though it never forms more than half of the canopy, as well as tamarack and white pine. The understory can include a wide variey of species, including interrupted fern, mad-dog skullcap, marsh marigold, and mosses. This dynamic community is considered by the Minnesota Department of Natural Resources to be "perhaps the most species rich-community in east-central Minnesota."
Sources:
"Minnesota Land Cover Classification System: User Manual." Version 5.3 Minnesota Department of Natural Resources, Central Region, 2004.
"Minnesota's Native Vegetation: A Key to Natural Communities" Version 1.5 Minnesota Department of Natural Resources, Natural Heritage Program, 1993.
Wovcha, D, Delaney, B, Nordquist, G. Minnesota's St. Croix River Valley and Anoka Sandplain: A Guide to Native Habitats Minneapolis: University of Minnesota, 1995.
