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plant species list for Foxborough's Lowland Hardwood Forest restoration area is provided in Appendix B of this report. Aspen Woodlands Aspen woodlands are typically mesic upland vegetation with 10 -70% tree cover, of which <25% is by conifers, with aspens comprising >70% of tree cover and herbaceous species comprising <30% of non -tree cover. Aspen woodlands occur primarily in the deciduous forest - woodland zone, with scattered groves in the prairie zone. Quaking aspen is the dominant canopy species in the community across most of its range. In north - central Minnesota, however, big - toothed aspens occasionally dominate the canopy, and in the northwest, balsam poplars sometimes dominate low, moist areas. Bur oaks and green ashes are common associates throughout the community's range. Stands of Aspen Woodland have either dense canopies of even -aged immature trees, irregular canopies of young and old trees, or tall, even canopies of mature trees. The woody understory in the community is well - developed, with 40 -90% cover. The understory may contain plants, including tree species, of several different height classes or it may have a well - defined shrub layer. On drier sites, hazelnut, gray -bark dogwood, chokecherry, downy arrow -wood, Rosa spp., and Rubus spp. are common understory shrubs. On wetter sites, the common understory shrubs are red -osier dogwood, gray -bark dogwood, pussy willow, Bebb's willow, bog birch, and meadow sweet. These species are particularly characteristic in Aspen Woodlands in northwestern Minnesota that originated following the invasion of areas of wet - mesic Upland Prairie or Wet Meadow by aspen. Aspen Woodland is a short-lived, early successional community intermediate between Upland Prairie (including Brush - Prairie) and Aspen or Oak Forests. Before European settlement, the distribution of Aspen Woodland in the prairie zone was determined by fire, with the community occurring in areas where fires were less frequent and intense than in open prairie areas. In the deciduous forest - woodland zone, Aspen Woodland probably was maintained by fire and occurred in association with Oak Forest, Aspen Forest, and some pine forests. Aspen Woodland has become more abundant in Minnesota because of fire suppression and perhaps wetland draining. Communities that originate following logging in the deciduous forest - woodland and conifer - hardwood forest zones often resemble Aspen Woodland but are not considered true Aspen Woodlands in this classification. When Aspen Woodland occurs with other related community types, such as Brush - Prairie and Aspen Openings, it tends to occur as narrow ecotonal bands between the other types or as small inclusions, and may be ignored in mapping. A comprehensive plant species list for Foxborough's Aspen Woodland restoration areas is provided in Appendix B of this report. Oak Savanna Oak savannas are upland plant communities with 10 -70% cover by trees (of which <25% is conifer), where >30% of non -tree cover is herbaceous (prairie - dominated) and where oaks comprise >30% of the tree cover. The soil is composed of sand or gravel (sometimes with a thin organic surface layer), or any texture on steep slopes. This dry to dry-mesic community is most common in the deciduous forest - woodland zone, but also occurs sporadically throughout the prairie zone. The principal trees are bur oaks and northern pin oaks, but black oaks are also Foxborough Conservation Development Restoration and Management Plan 18 • •