Taxonomic name: Pennisetum ciliare (L.) Link
Synonyms: Cenchrus ciliaris L., Cenchrus glaucus C. R. Mudaliar & Sundararaj, Pennisetum cenchroides Rich., Pennisetum incomptum Nees ex Steud.
Common names: African foxtail grass, Büffelgras (German), buffelgrass, cenchrus cilié (French), dhaman (Hindi), pasto buffel (Spanish), zacate buffel (Spanish)
Organism type: 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. Description
Buffel grass is a perennial bunchgrass with erect culms 10-150cm tall. It can form thick mats or tussocks with dense, usually stoloniferous root systems. The leaf blades are bluish-green in colour, 3-30cm long, with soft hairs on the upper surface. The inflorescence is generally cylindrical in outline, 2-14cm long, and can be purple, gray or yellowish. The spikelets are solitary or clustered, and are surrounded by numerous bristles (Martin, 2002). Occurs in:
agricultural areas, desert, range/grasslands, riparian zones, ruderal/disturbed, scrub/shrublands Habitat description
Buffel grass favours alkaline soils and within arid areas establishes best in pockets of high nutrients and moisture. Hacker and Ratcliff (1989) state that buffel grass does not spread rapidly in higher rainfall areas in Queensland, Australia, but is more invasive in the arid zones of central and western Australia where its resistance to fire drought and grazing makes it very persistant and dominate over native species by forming dense monocultures and displacing native species. General impacts
Buffel grass alters fire regimes. Buffel grass changes plant communities by encouraging and carrying wildfires through communities that are not adapted to fire. It burns readily (even when green) and recovers quickly after fire. Recurrent fires maintain P. ciliare populations, and the ecological result is a conversion of native desert scrub communities to an African-type savannah with reduced native biological diversity (McCormick et al. 1999). Brooks et al. (2004) identify methods by which new plant forms introduced to an existing vegetation stand through invasion can alter the extrinsic fuel properties of the stand. The authors observe that buffel grass in Australia alters the fire regime by increasing horizontal fuel continuity and thus increase in frequency and extent of the fire.Martin (2002) states that, "P. ciliare, in Hawaii, was planted for erosion control but is now replacing the native pili grass (Heteropogon contortus). The species biodiversity in alien-dominated communities is lower than the biodiversity in native pili grass communities (Daehler and Carino, 1998).
P. ciliare was also noted as one of the threats for the federally endangered species South Texas ambrosia (see Ambrosia cheiranthifolia in Endangered Species found in Texas) and Zapata bladderpod (see Lesquerella thamnophila in Federal Register Environmental Documents).
In upland arid regions, P. ciliare can transform native desert shrub and thornscrub into grasslands. In lowland riparian areas, P. ciliare can replace native riparian vegetation along riverbanks. By dominating these riparian areas and their moist refuges within arid regions, P. ciliare threatens keystone habitats that are vital to the survival of many plant and animal species (McCormick et al. 1999). Grice (2004) states that, "P. ciliare is structurally and functionally similar to the native, perennial, tussock grasses of central Australia, but it might be less useful to native granivores than the native grasses because of the characteristics of its seeds. Invasion by P. ciliare could therefore lead to a decline in the diversity of granivores." Uses
Buffel grass has been widely introduced and subsequently established in hot, semiarid regions of the world for forage and fodder (Van Devender et al. 1997). Notes
Pennisetum ciliare is also known by its basionym Cenchrus ciliaris. Geographical range
Native range: Africa, Asia, and Europe. (USDA-GRIN, 2003).
Known introduced range: Australia and North America (Tu, 2002). Introduction pathways to new locations
Agriculture: Buffel grass has been widely introduced in the dry tropics and subtropics as a pasture grass, for erosion control and revegetation of arid areas.
Local dispersal methods
Agriculture (local): Buffel grass has been widely introduced in the dry tropics and subtropics as a pasture grass, for erosion control and revegetation of arid areas.
On animals: The spiked seed-bearing involucre also increases spread by attaching to animals (Griffin 1993).
On animals (local): Wind is a major mechanism of dispersal of buffel grass seeds. Vehicle wind-assisted spread along roads is also evident in Uluru National Park (Griffin 1993).
On clothing/footwear: Seed is also easily spread by humans as they readily adhere to trousers and socks (Griffin 1993).
Water currents: Flood waters are a major mechanism of dispersal of buffel grass seeds. Griffen (1993) observes that buffel grass was
not reported as spreading in Australia until the 1970s, when high rainfall and floods lead to rapid colonisation along creeklines
and alluvial flats. Reproduction
Tu (2002) states that, "P. ciliare is bisexual (having both male and female flowers), with bisexual spikelets and hermaphrodite florets. P. ciliare can produce seed either sexually or by apomixis (asexual reproduction without fertilization or meiosis) (Van Devender et al. 1997 in Tu, 2002). It can also reproduce vegetatively, via rhizome or stolon sprouts." Ocumpaugh and Rodriguez (UNDATED) elaborate on the apomixis method of reproduction stating that, "All P. ciliare varieties reproduce by apomixis, where the embryo of the seed develops from an unreduced vegetative (somatic) cell in the ovule of the female and receives no genetic material from the male (Bashaw and Hanna 1990), resulting in plants that are identical to their maternal origin, or in other words, varietal clones. The apomixis trait is both an asset and a liability. It is an asset in that once we find a plant with good agronomic characteristics we can save the seed from it and it always breeds true, producing a very uniform variety. The liability is that the crossing of plants with good traits is not a one-step process since the use of the sexual clone is indispensable." Reviewed by: Expert review underway Principal sources: Van Devender, T. R; Felger, R. S and Burquez, A. M., 1997. Exotic plants in the Sonoran desert Region, Arizona and Sonora. California Exotic Pest Plants Council 1997 Symposium Proceedings.
Martin, T. 2002.Cenchrus ciliaris L. The Nature Conservancy: Wildland Invasive Species Team.
Tu, 2002 Element Stewardship Abstract for Cenchrus ciliaris L.
Compiled by: National Biological Information Infrastructure (NBII) & IUCN/SSC Invasive Species Specialist Group (ISSG)
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Last Modified: Thursday, 23 March 2006
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