Lupines are resourceful plants that grow in rocky rubble and on sand dunes where their root system may reach a depth of 20 feet. More importantly, lupines can obtain nitrogen from the atmosphere with the help of Rhizobium, a bacterium which grows in nodular swellings on the roots. These bacteria can convert atmospheric nitrogen into organic compounds in a process called nitrogen fixation. This symbiotic relationship allows the lupine to grow in nutrient poor soils. In return the lupine serves as a host that supplies energy-rich carbon compounds to the bacteria.
DISTRIBUTION: Open sandy or rocky habitats throughout the Calif. Floristic Province; < 2000 m.