lespedeza, (genus Lespedeza), genus of about 40 species of plants in the pea family (Fabaceae). All lespedezas are adapted to warm humid climates and are native to North America, tropical and East Asia, and Australia. A number of species are useful as forage and green manure crops, and some are used for erosion control or as ornamentals.
The lespedezas may be roughly grouped as herbaceous perennials, small shrubs, and annuals. They are either erect or trailing in habit, and some perennial species can reach heights up to 3 metres (10 feet). The best-known species have alternate, toothless leaves that are made up of three leaflets. The plants house symbiotic soil bacteria (rhizobia) in their root nodules to “fix” nitrogen from the air into the soil, thus making it accessible to other plants and improving the soil nutrient levels.
Sericea lespedeza (Lespedeza cuneata) is widely used in American agriculture as a pasture crop. Because of its great root system, its dense growth canopy, and its ability to grow on badly eroded soils, the sericea lespedeza is also extremely useful in soil conservation. Some shrublike lespedeza species, such as the bicolour lespedeza (L. bicolor), are grown as ornamentals.
Two widely used annual species have been reclassified: common lespedeza, or Japanese clover (Kummerowia striata, formerly L. striata), and the Korean lespedeza (K. stipulacea, formerly L. stipulacea), which are both native to Asia.