In the wet floodplains adjacent to the River Raisin in southeast Michigan I often find a variety of sedges (family Cyperaceae). Most often I see true sedges of the genus Carex, but last week I came across a flatsedge in the genus Cyperus:
Sedges are usually found in wet or moist areas, and many flatsedge species in particular are common along the banks of rivers and lakes. This individual was growing on an emergent mud flat exposed by a very low river level.
Sedges look somewhat like grasses and are in the same order (Poales). Grasses are distinct, however, and are separated into a different family (Poaceae). The easiest way to identify a sedge is to examine the cross-section of a shoot. Most sedges have trigonous shoots; they’re distinctly triangular in cross-section. Grasses, in contrast, are round.