Comprehensive DescriptionRead full entry
General: Grass Family (Poaceae). Bitter panicum is a native, perennial, rhizomatous, warm-season grass growing to a height of 4-8 feet with a growth habit ranging from erect to prostrate to decumbent. The leaves are 1/4 to 1/2 inch wide, 7 to 20 inches long, smooth without hair, and bluish in color. A robust grass, it spreads slowly from short, strong rhizomes or by rooting from lower nodes of plant stems (culms) to form open clumps. The inflorescence is a narrow panicle 12 to 15 inches in length that is contracted in maturity. Flowering begins in September and continues through December. Bitter panicum is a hexaploid (2n=54), consequently, seeds are consistently sterile. Small quantities of poor quality seed are produced on compact clusters 6 to 12 inches long and 2 to 4 inches wide. Reproduction is vegetative by lateral tillering from established plants. Plants can spread from an aggressive, scattered system of rhizomes, but the stands are rather open.
Distribution: The native range and distribution of bitter panicum is along the coastal beach system of the north central Gulf of Mexico basin. It is also distributed throughout the East and lower Midwest; it can be found along the Atlantic Ocean and the Gulf of Mexico from Connecticut to northeastern Mexico. It is also found as an introduction in a few inland locations in New Mexico, North Carolina, and West Virginia, as well as in the Bahamas and Cuba. For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site.
Habitat: Bitter panicum grows on coastal dunes, in interdunal swales, overwash sands, wet sandy soils, low fertility soils, and the margins of swamps. On coastal dunes, it is most likely found in the lower foredune slopes of the frontal zone, which is closest to the ocean and supports mainly grasses and other herbaceous plants tolerant of exposure to salt spray. It also occurs on dune crests, as well as in the backshore area near dunes and on both the leeward and the windward slopes of dunes or dune ridges. It favors exposed areas where windblown sand accumulates.
In the southeastern U.S., bitter panicum is equally likely to occur in wetlands or non-wetlands (estimated probability 34%-66%). In the northeast and the southern plains it usually occurs in non-wetlands (estimated probability 67%-99%), and is only occasionally found on wetlands (estimated probability 1%-33%).