Poaceae are dominant are estimated to constitute 40.5% of the land area of the Earth, excluding Greenland and Antarctica. Grasses are also an important part of the vegetation in many other habitats, including wetlands, forests and tundra. The Poaceae are the most economically important plant family, providing staple foods from domesticated cereal crops such as maize, wheat, rice, barley, and millet as well as forage, building materials (bamboo, thatch, straw) and fuel (ethanol). Though they are commonly called "grasses", seagrasses, rushes, and sedges fall outside this family. The rushes and sedges are related to the Poaceae, being members of the order
Orobanche minor nomenclatural problems that have historically been linked with this species. The common broomrape is highly generalist in its host range, and can infect hundreds of species in families from the Ranunculaceae to the Poaceae (=Gramineae) but with a clear preference for the Fabaceae (=Leguminosae) and Asteraceae (=Compositae). However races occurring on different species of host are genetically divergent and physiologically adapted to their local hosts, and may therefore be in a state of incipient speciation. Urgent conservation efforts are required as the survival of some intraspecific taxa is very uncertain. Orobanche minor Orobanche minor, (hellroot, common broomrape, lesser broomrape, small