05/30/2001 Env Bd Packet - Laserfiche WebLink

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At the base of the savanna slopes along the southern perimeter of the project area is a forested wetland system dominated by green ash (Fraxinus pennsylvanica), with occasional cottonwood (Populus deltoides), basswood (Tilia americana), silver maple (Acer saccharinum), and American and red elm (Ulmus americana, U. rubra). The majority of the existing forested wetland system consists of trees of a very young age. Dense thickets of prickly ash (Xanthoxylum americanum) are present in slightly elevated areas. Thickets of hackberry (Celtis occidentalis) and boxelder (Acer negundo) occur in other locations. Shrubs scattered within the forested wetland, primarily in Tight gaps, include silky and red osier dogwood (Comus amomum, C. stolonifera). In some locations there are dense patches of black and red raspberry (Rubus occidentalis, R. strigosus). The majority of the ground story vegetation in the forested wetland area is dominated by reed canary grass, with stinging nettle as a co- dominant. In many locations, apparently in association with seepage zones, canary grass has crept into the upland, where it mingles with northern pin oak (Quercus palustris), Pennsylvania sedge (Carex pensylvanica), wild black cherry (Prunus serotina), and hackberry. Stands of ferns, such as hay- scented fern (Denstatia sp.), and sensitive fern (Osmunda sensibilis), are often found growing in association with alder (Alnus rugosa). Historically, this area likely existed as a sedge meadow ecotonal area dominated by blue joint grass (Calamagrostis canadensis) and a variety of sedges, ferns, and forbs. Slightly elevated areas, created by root mounds of trees, may have supported paper birch (Betula papyrifera), alder, American hazel (Corylus americana), silky dogwood, and other woody species. Because of the heavy shading and de- watering of peat and muck soils effected by the present young tree and shrub cover, not only has ground story vegetation declined, but many species such as stinging nettle (Urtica dioica) and canary grass, favored in these nutrient -rich, de- watered muck soils, have become dominants. This de- watering impact has also allowed for more tree and shrub invasion and allowed for quicker growth by those trees and shrubs that are present. In other words, tree and shrub cover has increased so substantially and de- watered the site so substantially that now even upland species are invading into the former historic wetland system. Recommendation: Restoration and management of this area would involve brushing, prescribed buming, and herbicide treatment of canary grass and other weeds. Restoration of hydrology may S:98629:040999 8 Lino Lakes Town Center Natural Resource Inventory Report