Greenan ASSI

Greenan is a basin fen. A fen is a poorly drained wetland area with a permanently high water level at or just below the surface. The complex variety of habitats that can occur within a fen contributes to the rich diversity of plants and animals. Although small, Greenan has a range of vegetation types, including some notable fen communities and species.

The centre of the area is a mosaic of open water and swamp, with pockets of more diverse acid fen. The swamp is dominated by bottle sedge with frequent associated species including a number of floating moss mats.

To the north, there is an unusual fen community dominated by water horsetail and ragged Robin growing over a variable moss layer. This community is one of the most diverse in the area. Notable plants include greater bladderwort, floating club-rush, marsh St. Johns-wort and the moss Sphagnum squarrosum.