You searched for invasive species named Pennisetum:    

1. Pennisetum ciliare (grass)   

Pennisetum ciliare, commonly known as buffel grass, is a perennial bunchgrass that forms thick mats. It is also known by its basionym Cenchrus ciliaris. Buffel grass has been widely introduced in the dry tropics and subtropics as a pasture grass, for erosion control and revegetation of arid areas. The characteristics of buffel grass which make it suitable for erosion control are rapid germination, high propogation and establishment rates on poor and infertile soils. Pennisetum ciliare's dominance and resistance to fire, drought and heavy grazing on arid soils make it a suitable arid zone pasture grass. In Australia, the south-western United States and Mexico (where it has been introduced as a pasture grass and for erosion control) Pennisetum ciliare often forms extensive dense monocultures excluding native species and promoting intense and frequent fires. It is widely distributed and is resilient to a number of harsh environmental conditions. Pennisetum ciliare changes plant communities by encouraging and carrying wildfires through communities that are not adapted to fire. It burns readily and recovers quickly after fire. Pennisetum ciliare has a robust root system; its swollen stem base accumulates carbohydrate reserves, so the loss of leaf surface area after a fire or drought is not fatal to the plant and allows regrowth in favourable conditions.

Common Names: African foxtail grass, Büffelgras, buffelgrass , cenchrus cilié, dhaman, pasto buffel, zacate buffel

Synonyms: Cenchrus ciliaris L., Cenchrus glaucus C. R. Mudaliar & Sundararaj, Pennisetum cenchroides Rich., Pennisetum incomptum Nees ex Steud.

2. Pennisetum clandestinum (grass)     

Pennisetum clandestinum is a creeping, mat-forming grass that originates from tropical eastern Africa. It gets its common name, kikuyu grass, from the fact that it is native to the area in which the Kikuyu tribe live. Pennisetum clandestinum is an aggressive invader of pasture, crops and natural areas. It spreads via an extensive network of rhizomes and stolons, and smothers all other vegetation. It is difficult to control manually, but the use of herbicides can yield good results.

Common Names: capim-quicuio, kikuyo, kikuyu grass, kikuyu pul, kikuyu tana, kikuyugras, pasto africano, West African pennisetum, xi fei lang wei cao

Synonyms: Pennisetum inclusum Pilg., Pennisetum longstylum Hochst., Pennisetum longstylum var. clandestinum (Hochst. ex Chiov.) Leeke

3. Pennisetum macrourum (grass)   

Pennisetum macrourum (African feather grass) is a 1 to 1.8 metre erect perennial grass native to South Africa. It has been introduced to New Zealand and Australia, where it has established and is known to replace desirable stock grass with grass of low palatability in pastoral areas.

Common Names: African feather grass, African feathergrass, bedding grass, feather grass, fountain grass , kikuyu grass, needle grass, spear grass, waterside reed

Synonyms: Pennisetum angolense Rendle, Pennisetum giganteum A. Rich., Pennisetum quartinianum A. Rich

4. Pennisetum polystachion (grass)     

Pennisetum polystachion (alternative spelling Pennisetum polystachyon) is a large grass species originating from Africa and India. It has spread to many Pacific islands and thrives in tropical climates. Pennisetum polystachion causes major problems in the Northern Territory of Australia, where it has greatly increased the amount of flammable material in the wooded savanna ecosystem, leading to greater devastation from bushfires.

Common Names: dipw rais, feathery pennisetum, mechen katu, missiongrass, o tamata, pwokso, queue de chat, thin napier grass, West Indian pennisetum

Synonyms: Cenchrus setosus Sw. 1788, Gymnotrix geniculata Schult. 1824, Panicum barbatum Roxb. 1820, Panicum cauda-ratti Schumach. 1827, Panicum cenchroides Rich. 1792, Panicum densispicum Poir. 1816, Panicum erubescens Willd. 1809, Panicum polystachion L. 1759, Panicum subangustum Schumach., Panicum triticoides Poir. 1816, Pennisetum alopecuroides Desv. ex Ham. 1825, Pennisetum atrichum Stapf & C.E.Hubb. 1933, Pennisetum borbonicum Kunth 1830, Pennisetum cauda-ratti (Schumach.) Franch. 1895, Pennisetum elegans Nees ex Steud. 1854, Pennisetum erubescens (Willd.) Link 1827, Pennisetum flavescens J.Presl 1830, Pennisetum gabonense Franch. 1895, Pennisetum gracile Benth. 1849, Pennisetum hamiltonii Steud. 1841, Pennisetum hirsutum Nees 1829, Pennisetum indicum Murray var. purpurascens (Kunth) Kuntze 1891, Pennisetum nicaraguense E.Fourn. 1880, Pennisetum pallidum Nees 1829, Pennisetum polystachion (L.) Schult. subsp. setosum (Sw.) Brunken 1979, Pennisetum polystachion (L.) Schult. subsp. atrichum (Stapf & C.E.Hubb.) Brunken 1979, Pennisetum purpurascens Kunth 1816 , Pennisetum reversum Hack. ex Buettner var. gymnochaetium Hack. 1901, Pennisetum reversum Hack. ex Buettner 1890, Pennisetum richardii Kunth 1829, Pennisetum setosum (Sw.) L. Rich., Pennisetum setosum (Sw.) Rich. 1805, Pennisetum sieberi Kunth 1829, Pennisetum stenostachyum Peter 1930, Pennisetum subangustum (Schumach.) Stapf & C.E.Hubb. 1933, Pennisetum tenuispiculatum Steud. 1854, Pennisetum uniflorum Kunth 1816 , Setaria cenchroides (Rich.) Roem. & Schult. 1817, Setaria erubescens (Willd.) P.Beauv. 1812

5. Pennisetum setaceum (grass)     

Pennisetum setaceum was introduced to the United States as an ornamental grass. It reproduces high numbers of wind-dispersed seeds that have spread outside of planted areas. Pennisetum setaceum is a desert plant that is prevalent along roadsides, washes and canyons where the annual rainfall is less than 127cm. Pennisetum setaceum interferes with natural fire regimes and competes with native species for limited resources.

Common Names: fountaingrass, yerba de fuente

Synonyms: Pennisetum ruppelii Steud., Phalaris setacea Forsk.

6. Setaria verticillata (grass)   

Setaria verticillata is a native European grass, invading agricultural, urban, and other disturbed areas throughout North America, Central America, South America Africa, Asia, and the North and South Pacific. A problematic crop weed S. verticillata, has inflicted considerable environmental and economic costs, is known to adapt to local conditions rapidly, and has developed resistance to atrazine and other C 1/5 herbicides.

Common Names: almorejo, almorejo verticilado, alorejo, amor de hortelano, bristly foxtail, bur bristle grass, bur grass, capim-grama, carreig, cola de zorro, dukhain, fieno stellino, foxtail, hooked bristlegrass, kamala, khishin, kirpi dari, Kletten Borstenhirse, kolvhirs, Kransnaaldaar, lagartera, lossaig, mau‘ pilipili , milha-verticilada, oehoe, panico maggiore, panissola, pata de gallina, pega-pega, pega-saias, quam el-far, Quirl Bortenhirse, rabo de zorro, rough bristle grass, setaire verticillée, whorled pigeon grass, Wirtel Borstenhirse, yah hang chnig-chok, zacate pegarropa, zaratsukienokorogusa

Synonyms: Chaetochloa verticillata (L.) (Scribn.), Ixophorus verticillatus (L.) (Nash, 1859), Panicum adhaerens (Forssk., 1775), Panicum aparine (Steud., 1854) , Panicum asperum (Lamk., 1778), Panicum respiciens (A. Rich., 1854), Panicum rottleri (Nees, 1841) , Panicum verticillatum (L., 1762), Panicum verticillatum L., Pennisetum respiciens (A. Rich., 1851) , Pennisetum verticillatum (L.) (Nash, 1817), Pennisetum verticillatum R. Br., Setaria adhaerens (Forssk., 1919), Setaria ambigua (Guss.), Setaria aparine (Stued. 1912), Setaria carnei (A.S. Hitchc.), Setaria nubica (Link), Setaria respiciens (A. Rich, 1852), Setaria verticillformis (Dumort.), Setaria virdis (Terracc., 1894)