Reed Manna Grass Glyceria maxima
Ecology and Natural History: Reed manna grass is native to temperate Eurasia. It is typically found in marshes, meadows, and along shorelines. It usually reproduces by rhizome. It is thought to be introduced intentionally as a forage species or an ornamental plant.
Impacts of Introduction: Reed manna grass can form large monotypic stands, reducing diversity. Since growth begins in early spring, it can easily out-compete other species by beating them to valuable resources. Reed manna grass is an ecosystem engineer that can change an entire wetland by converting fast-flowing, oxygen-filled streams into partially anaerobic swamps.