Japanese stiltgrass (Microstegium vimineum) Identification and Management: Brief Description: Japanese stiltgrass (also known as annual jewgrass, bamboograss flexible sesagrass, Japanese grass, Mary’s grass, microstegium, Nepal microstegium, or Vietnamese grass) is a summer annual commonly found in shady, moist areas, and is spreading rapidly in woodlands as well as shaded landscapes and low maintenance turf throughout the southeastern U.S., Mid-Atlantic States and north to New England. Japanese stiltgrass germinates in early spring, several weeks before crabgrass, yet flowers and seeds much later, from mid-September through October. It has broader, shorter leaves than most other annual grasses; somewhat resembling broadleaf signalgrass or spreading dayflower. After frost, the foliage and wiry stems turn a distinctive light tan in color and persist through the winter. Vegetative identification characteristics include: rolled vernation, a very short membranous ligule, and leaf blades that are shorter and broader than most other grasses.