Muhlenbergia racemosa is a species of grass known by the common names green muhly and marsh muhly. It is native to North America, where it is most common in the north-central United States. It also occurs in the western United States and northern Mexico. This plant is a rhizomatous perennial grass with usually erect, branching stems up to 1.3 meters tall. The flat leaves are up to 18 centimeters long. The inflorescence is a narrow panicle up to 16 centimeters long.