A fast-growing grass with allelopathic chemicals, this plant competes aggressively with native vegetation. It can form dense monocultural stands and displace other species along river and lake shorelines, in canals, marshes, and swamps (Langeland and Burks, 1998). Listed as a category I invasive species by Florida Pest Plant Council.
Perennial grass from widely creeping stolons. Stems reclining at base, rooting at the lower nodes, to 1 m (3 ft) tall when erect, to 3 m (15 ft) long when creeping; nodes swollen, densely hairy. Leaf shealths with dense stiff hairs below, slightly hairy above; ligule a densely ciliate member; leaf blades flat, 10-15 mm (0.4-0.6 in) wide and 25-30 cm (10-12 in) long, glabrous but often with small fine hairs at base above and below. Inflorecence a terminal panicle to 20 cm (8 in) long, with 8-20 ascending, alternate branches; spikelets (reduced flowers) dense on the branches, paired, each at 3mm long, glabrous, often purple tinged.
The panicle-like inflorescence of paragrass provides the surest method of identification.
Introduced to Florida in the 1870 (Langeland and Burks, 1998).
Found in central and south Florida from Pinellas on the west to Brevard on the east and south to the Florida Keys (Langeland and Burks, 1998).
Do not plant. Report infestations to Florida Exotic Pest Plant Council's Early Detection & Distribution Mapping System.