Uncommon, curious-looking small fern with curly, wiry vegetative fronds that look like curly grass.  The fertile, spore-bearing fronds are upright and turn brown when mature.  Found in wet, peaty soils (e.g., bogs), often on hummocks.  Photographed at Webbs Mill Bog.

May.  Fertile brown fronds from previous year, and developing fertile green fronds for current year.

June.  Vegetative fronds.