Nelson Lake Marsh

Description

The natural features occurring at Nelson Lake Marsh Preserve include marsh, fen and open water communities with woodland and savanna communities occupying the borders. The marsh, lake and fen are the main features. The basin of the marsh was formed over 10,000 years ago during the Pleistocene glaciation when a persisting ice mass produced the large depression. Today the floor of the basin consists of Houghton muck, a very poorly drained soil formed by organic deposits often more than 50" thick. To the north, floating peat mats often fuse together creating a large cattail marsh. Swamp milkweed, great water dock and water parsnip are common in this community, with mad-dog-skullcap, blue flag and clearweed in patches of low growth cleared by muskrat and beaver. The 40-acre lake provides a stable aquatic habitat. In the summer the lake is covered with a dense tangle of aquatic plants, including duckweed, hornwort, coontail and great bladderwort. In mid-July the lake is blanketed with white water lilies. The preserve is very important to wildlife including rare and endangered types. Significant populations of invertebrates include localized species of butterflies such as swamp metalmark, meadow fritillary, purplish copper and Baltimore checkerspot. Interesting birds such as American bittern, Wilson's phalarope, black tern, sandhill crane and northern harrier have been observed in the spring and summer months. This nature preserve is represented on two topos, Sugar Grove and Aurora North 7.5