Bush clover, also known as Sericea Lespedeza, is a weedy legume. It was initially considered a great ground cover in mid-America because of its nitrogen-fixing properties. In the 1960’s it was used as an erosion control measure and it was able to grow in drought conditions. Within 20 years, the view of bush clover changed as it morphed into an invasive weed taking over wildlife habitats and native vegetation. While there are over 60 different varieties of Lespedeza in the world, most of which are native to Asia.
Bush clover is a perennial weed that will easily take over turf or landscaping and strangle out grass and desired plants. It produces purple and white flowers. It thrives in late summer and has semi-woody root systems that grow close to the ground, making it difficult to mow. It is also commonly known as Lespedeza clover, Japanese clover, and some refer to it as the devil’s own weed. This because cattle won’t eat it due to the high levels of tannins in the plant, herbicides don’t generally work to eliminate them in larger pastures and fields, and proper range management perpetuates the weed and helps it thrive. It is known as the only plant we are currently aware of that invades prairie land and crowds out native prairie grasses. Plants are freely branched with three oblong leaflets with perpendicular stems.
Most forms of bush clovers originated in eastern Asia. Introduction in the United States started in the 20th century as a measure to prevent erosion control. However, they have quickly spread throughout the country and are considered invasive weeds. Bush clover will grow in almost any habitat, including pastures, rangelands, prairies, eroded slopes, and roadsides.
One of the most prominent characteristics of bush clover is that its seeds can remain dormant for as many as 20 years. In some cases, seeds kept in dry storage for 55 years have a 60% chance of germinating new weeds. As summer fades into the dog days, stems become woody and roots provide a matted web close to the ground. Bush clover can produce as many as 1500 seeds, which is part of the reason why it is so difficult to control. As winter approaches, weeds will die back to the roots, and new growth will begin once weather conditions permit in the late spring and early summer. Humans have used Bush clover for medicinal and astringent purposes because of the high levels of tannins. However, most livestock and cattle will not eat it as the tannins make it unpalatable, and it prevents the absorption of necessary nutrients when consumed. It may sometimes be used as a type of hay that is nutrient-packed that is more palatable for livestock as tannin levels decrease when dried.
The best weed control measures for controlling bush clover utilize cultural methods to prevent overgrowth of plants. Control bush clover through mowing carefully, cutting it back before it has the opportunity to produce seeds. Keep grass length no shorter than 3″ to avoid it crowding out turf. Additionally, checking soil’s pH levels will help make sure soil is providing adequate conditions for turf growth. Pre-emergent weed control can also be beneficial on most grass types. Spreading gluten cornmeal in early spring can help as a pre-emergent weed control measure. If possible, remove infestations manually. Hand-pulling is recommended if bush clover is found near other plants and flowers that are desired in turf and landscape. Non-selective herbicides may be used, but should be done so with extreme caution as it will kill other desired greenery surrounding it. Weed control plans offered by most reputable and licensed weed control services should be able to take care of this weed in your lawn.