[Wikipedia] Common Name, Endangered Status: Nassella cernua (syn. Stipa cernua) is a species of grass known by the common name nodding needlegrass. This and many other native grasses of the California Floristic Province have declined because of the encroachment of introduced species of grasses, making native grasslands a very endangered habitat type, and this plant a listed Vulnerable species.[1] (link added by Mary Ann Machi)