Synonym(s): Panicum maximum,
Family: Poaceae (Grass Family)
Duration and Habit: Perennial Grass/Grasslike
U. maxima is described as a tufted perennial, often with a short creeping rhizome, variable 60-200 cm high, leaf blades up to 35 mm wide tapering to a fine point; panicle 12-40 cm long, open spikelets 3-3.5 mm long, obtuse, green or purplish, glumes unequal, the lower one being one-third to one fourth as long as the spikelet, lower floret usually male or empty depending on the variety. Upper floret (seed) distinctly transversely wrinkled lemma and palea. The grain is about 2mm long
Native Lookalikes: Currently no information available, or there are no native species that could be confused with Guineagrass.
Ecological Threat: U. maxima forms dense stands in open pastures and disturbed areas. Guinea grass can suppresses or displace local plants on fertile soils in pastures Its resistance to drought also means it builds up a dangerous mass of plant material so when fires occur, the blaze is fiercer and native plants which have not built up fire-tolerance are wiped out. As guinea Grass can survive fires, it can dominate the ground after a fire.
Biology & Spread: Seeds profusely but seeds are of low germination, often empty and do not survive long. The seeds are dispersed short distances by wind. Fire will sweep through stands of this grass but it regenerates rapidly from underground rhizomes
U.S. Habitat: agricultural areas, riparian zones, disturbed
U.S. Nativity: Introduced to U.S.
Native Origin: Africa
U.S. Present: AZ, CA, FL, GA, HI, LA, TX
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Physical: Hand pulling / grubbing also works, but spraying seems easier.
Chemical: Susceptible to glyphosate and readily controlled by drizzle applications. Young plants are susceptible to selective grass-killers.
Biological: Plants die rapidly under close continuous grazing.
IUCN/SSC Invasive Species Specialist Group (ISSG. 2006. Urochloa maxima (grass). Accessed 25 November 2008: http://www.invasivespecies.net/database/species/ecology.asp?si=398&fr=1&sts=
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