Muhlenbergia glomerata is a species of grass known by the common names spiked muhly and marsh muhly. It is native to North America, where it occurs across Canada and the northern half of the United States.
This grass is found in moist areas in various habitat types. It grows in bogs, marshes, meadows, ditches, fens, swamps, riversides and lakeshores, hot springs, wet forests, alvars, and seasonally flooded land. It occurs in cooler, more moist places than many other C4 species. It occurs less often in dry places.