Leymus racemosus (Lam.) Tzvelev

Leymus racemosus (Lam.) Tzvelev. Leymus racemosus is a species of perennial wild rye known by the common name mammoth wild rye. It is native to southeastern and eastern Europe, Middle Asia, the Caucasus, Siberia, China, Mongolia, and parts of North America. In New Zealand, it is an introduced species and is regarded as an environmental weed. Culms are 50–100 cm long, and 10–12 mm in diameter.