Green Lake Fen (Esker Bog)

A North Algona Wilberforce Township 81.5-ha regionally significant Life Science ANSI.

Green Lake Esker ANSI contains Late Wisconsinan series of esker ridges. The sinuous esker ridges stand in sharp contrast to the flat surface of the bog. The bog deposits are extensive, at least 11m thick. The internal structure of the eskers is evident in the road cut and in the many gravel pits. [Earth Science Database, 1998]

A Black Spruce - Larch coniferous intolerant lowland forest dominates a shallow peatland occurring north and west of Green Lake. It extends north of Marsh Road where it becomes a slightly domed, dry, ericaceous shrub-dominated peatland upon which White Pine and White Birch are invading. The treed peatland south of Marsh Road is wetter and grades into a open fen peatland at the mouth of the small creek on the west side of Green Lake. A Reed-grass (Phragmites australis) marsh occupies the shallow water in front of the shrubby fen area. [Brunton 1991]

The site is on Outwash and Lacustrine landform at the edge of Marine Deposit landform and just north of an area of the area of marble bedrock. [Brunton 1991]

Fens are rare in the site district, and no other areas of apparently true fen are known, thus offering additional significance to this otherwise seriously limited site. [Brunton 1991]