Buffel Grass (Cenchrus Ciliaris)

Managing weeds for biodiversity

● Recorded distribution Buffel grass (Cenchrus ciliaris)

The problem fertile parts of the landscape, important address the problem of weeds that are for the survival of native plant and also considered useful. Buffel grass (Cenchrus ciliaris) is an animal populations in this highly variable Buffel grass is just one of many introduced, perennial pasture grass that climate. Although it was planted for perennial grasses invading Australia’s Buffel grass is found across much of the Australian dust control in central Australia, it also native vegetation, particularly grassy continent, including arid and semi-arid imposes economic costs through the plant communities, rangelands and regions. For many decades it has been need to manage fire risks and to protect coastal areas. Grasses introduced widely planted for livestock production biodiversity assets and infrastructure. as pastures, such as gamba grass and land rehabilitation. Its palatability Some pastoralists are also concerned – Cenchrus ciliaris (Andropogon gayanus), mission grass is moderate but it is well regarded as that productivity of buffel grass- (Pennisetum polystachion) and pasture because it grows rapidly under dominated pastures can decline in the Birdwood grass (Cenchrus setiger) are warm, moist conditions and persists longer term. a particular threat to tropical savannas under heavy grazing and drought. Buffel Buffel grass has been identified in northern Australia. grass has spread well beyond planted as a major threat to biodiversity in areas and dominates the ground layer regional natural resource management in many native plant communities. It strategies across Australia (SA Arid Key points reduces native plant diversity and can Lands, Rangelands (WA), Fitzroy affect vegetation structure by changing • Buffel grass is widespread in central and (Queensland) and the Northern fire regimes. In arid Australia, buffel northern Australia and has invaded a range Territory). It is becoming recognised grass invades some of the wetter, more of native plant communities. that new policies are needed to • It can dominate the ground layer, displacing native grasses and other plants. • Its rapid regrowth and high biomass may alter the intensity, frequency and extent of fires, changing vegetation structure and composition. • Buffel grass is still spreading, assisted by continued planting and new cultivars. • Its seed is readily dispersed by wind, water and animals. • Control measures can reduce impacts at sites of high conservation significance. • Mature plants are difficult to remove physically. Herbicide can be effective if applied when plants are actively growing and follow-up action is undertaken. Correct timing is essential. • The value of buffel grass as a pasture species is well recognised and it is not a declared weed.

Buffel grass (Cenchrus ciliaris) can dominate the understorey in arid regions. Central Australia, NT. Public policy issues arising from its positive Photo: R. Davies and negative aspects need to be resolved. 2

The weed with one longer bristle, 8–16 mm long. The bristles are joined at the very base Numerous forms of buffel grass have into a disc. Mature burrs contain a small been imported to Australia from across seed (<2 mm long) and are dispersed its native range. They differ in their by wind, water, animals, clothing, 1 cm drought, temperature and soil tolerance, boots and vehicles. growth form, palatability, and in quantity Birdwood grass (Cenchrus setiger) seed head and timing of seed production. Eleven lacks long, fine bristles. Advantages, have been registered as cultivars in Photo: Jose Hernandez @ USDA-NRCS PLANTS Database disadvantages and Australia. Two closely related species, broader impacts of Cenchrus pennisetiformis (Cloncurry 1.5 m tall, others are less than 1 m tall. grass) and C. setiger (Birdwood grass), buffel grass Some have rhizomes up to 0.5 m long. have also been planted as pastures in The tough, branched stalks have swollen Buffel grass has proved useful for Australia and are naturalised. Their range bases and produce leaves at the basal pasture and soil retention in a wide is similar, but they are less common and higher nodes. Leaves are rough- range of environments due to its than C. ciliaris. textured downwards, hairless or with drought tolerance, high biomass, deep The most common uses of buffel grass fairly sparse, long hairs. Leaf blades roots, rapid response to summer rains, in Australia are: have prominent midribs and leaf relative palatability and resistance to • as a pasture for livestock production sheaths are keeled. The ligule at the overgrazing. It produces viable seed so in semi-arid and arid lands (where junction of the leaf blade and sheath that stands can be self-replacing and sowing often follows native is a row of hairs, 0.2–2 mm long. pastures may not need to be reseeded. vegetation clearing) These same characteristics also make The flower head is cylindrical, erect, it an environmental weed. • to stabilise areas disturbed by

– Cenchrus ciliaris dense, spike-like, 2.5–15 cm long and mining, infrastructure development varies in colour from straw-coloured to Like any pasture species, buffel grass or overgrazing. purple. It consists of bristly burrs borne has limitations, such as: Buffel grass is a long-lived tussock on a zigzag central axis. The burr has • Through competition with native grass with a deep, tough root system. whorls of flexible bristles, a thin outer species, it reduces diversity of pasture Buffel grass Buffel While some cultivars can grow up to whorl and a ciliate (hairy) inner whorl including native grasses that are highly valued fodder after rain. The Buffel grass (Cenchrus ciliaris) effect may be exacerbated by selective grazing of more palatable species. • The initial increase in productivity when buffel grass pasture is established is not always maintained, and pastures may run down over time (10 years or less in some soils), especially where environmental conditions do not favour legumes. Flowering head. Shedding seed head, with zigzag axis. This problem is difficult to address Image: M. Robertson Image: M. Robertson in a cost-effective manner, especially on less productive lands. • Once buffel grass has been established as the dominant ground cover, conversion to an alternative pasture would be prohibitively expensive. • Some cultivars are more palatable than others. The less palatable forms may gradually become Burr. Ligule at the junction of leaf blade and sheath dominant in grazing lands through Image: M. Robertson is a fringe of hairs, 0.2–2 mm long. Image: M. Robertson selective grazing.

Weed Management Guide • Buffel grass – Cenchrus ciliaris 3

• Old leaves and stalks may persist for several years and are of no value to stock but may restrict their access to fresh growth.

Broader environmental impacts of buffel grass include the following: • Dry buffel grass foliage forms a relatively continuous flammable ground layer that can carry extensive and intense fires. It recovers its biomass very rapidly when moisture is sufficient and can burn when partly green. Therefore it can carry fire at much shorter intervals than native understorey. More frequent hot fires alter native plant community Mature buffel grass (Cenchrus ciliaris) tussocks grow rapidly after summer rains. Uluru NT. Photo: R. Davies structure because established trees Buffel grass and shrubs can be killed and young ones destroyed before they have • Restoration of native vegetation produced seed. on previously cleared lands may • Patch burning is needed in some be needed for recovery of threatened – Cenchrus ciliaris native vegetation types such as species or ecological communities. hummock (Triodia) grasslands to Buffel grass can be a major constraint maintain biodiversity and bush food to such efforts. resources, and to reduce the risk of large wildfires. It becomes more Weed identification and difficult to manage after buffel grass similar native species

has invaded the landscape. Mossman River grass (Cenchrus echinatus) A number of grasses in the genus • Food sources and habitat for native is a spiny annual weed in both northern and Cenchrus and the closely related genus southern Australia. fauna may be altered. In particular, Photo: C. Wilson Pennisetum occur in Australia, including native grass seed that is eaten by native and introduced, annual and granivorous birds can be depleted, perennial species. Most have flower P. pennisetiforme. Burrs of buffel grass and habitat patchiness and diversity heads that are spike-like, consisting of and Cloncurry buffel grass have soft, of invertebrates reduced. Loss of a central axis bearing numerous hairy, ciliate bristles but these are lacking in trees and shrubs to fire reduces bristly or spiny burrs that are actually Birdwood grass. Other Cenchrus species habitat diversity. very short floral branches. in Australia are native perennials and • Native plants affected by invasion introduced annuals. of buffel grass provide a diminished How to identify Cenchrus resource for traditional indigenous Annual Cenchrus species with spiny species livelihoods including bush food, burrs can be a nuisance and are often timber and medicine. The introduced perennial pasture declared noxious. Mossman River grass • Where buffel grass pasture occurs species, buffel grass (Cenchrus ciliaris), (C. echinatus) is the most widespread adjacent to fire-sensitive native Birdwood grass (C. setiger) and in Australia. Innocent weed or gentle vegetation, it can burn hot enough Cloncurry, white or slender buffel grass Annie (C. longispinus) is most prevalent to carry fire into the remnants, (C. pennisetiformis) have burrs that lack in the south, especially along the Murray opening up the canopy. The edges sharp, rigid spines. They are closely River. Indian sandburr or Gallon’s curse are then more prone to degradation, related—in fact C. pennisetiformis and (C. biflorus) is naturalised in northern including by weed invasion. In this C. ciliaris are sometimes considered to Australia. C. brownii occurs along the way, the area and integrity of habitat be the same species. Alternative species northern coast and offshore islands can be progressively reduced. names for the buffel grasses are and spiny burr-grass (C. incertus) occurs Pennisetum ciliare, P. setigerum and mainly in eastern Australia.

Weed Management Guide • Buffel grass – Cenchrus ciliaris 4

locally established along their routes. Buffel grass can survive in areas with Some of its early spread may have average rainfall of more than 200 mm been deliberate. From 1910 buffel grass annually (or 170 mm in summer). was actively distributed for planting It occurs naturally in regions having as pasture, initially in WA, then more up to 1000 mm annual rainfall. Under widely. Introductions of new forms higher rainfall, tropical conditions or in from Africa began in the 1920s and regions with winter rainfall of 400 mm were evaluated by government agencies, or more, buffel grass is less competitive mainly in NSW and Queensland. From with other plant species, including the 1940s seed was imported from perennial grasses. around the world for trials. There is In northern and central Australia buffel evidence that buffel grass had been Native species: black bottle-washers grass occurs mainly in the semi-arid to planted in central Australia before (Enneapogon nigricans). arid zone. In arid regions it is most Photo: T. Reynolds systematic planting for land rehabilitation common along ephemeral watercourses, began there in the 1960s. Prior to on alluvial plains, other run-on sites Similar native species 1972, nine introduced forms had been and calcareous rises. It thrives in sandy registered as cultivars in Australia and The native Cenchrus species loam but may be slow to establish on their seed produced commercially. (C. elymoides, C. robustus and heavy clay and prefers neutral to alkaline Buffel grass pastures have been sown C. caliculatus) are perennial, with various soils. It is not highly tolerant of severe in a range of environments across burrs, but lacking the long flexible frost or prolonged water logging. Australia, on land cleared for the bristles of buffel grasses and most purpose, or into native vegetation. At the local scale, studies in central Pennisetum species. C. elymoides is Australia have found that buffel grass confined to the tropics of northern Buffel grass spreads through dispersal

– Cenchrus ciliaris is most likely to be found nearer to Australia (Kimberley, northern NT and of its fluffy burrs by wind, water and drainages and tracks, in less rugged Cape York regions). C. robustus and animals, particularly along drainage terrain, with lower hummock grass C. caliculatus mainly occur in the eastern lines and roads. Its spread along roads cover and on soils with greater clay districts of Queensland and NSW. The can also be assisted by vehicle draughts content than rocky slopes or sand

Buffel grass Buffel flower head of C. caliculatus is loosely and movement of soil by graders and plains. Drainage lines and tracks packed, 4–24 cm long; its burrs have other vehicles. Buffel grass may be provide opportunities for dispersal and rigid inner bristles (4–11 mm long) and slow to establish initially but it may also favourable sites for establishment are often dark purplish. C. robustus then spread readily beyond planted (disturbed or bare ground, higher fertility, has 45–60 rigid, 9–13 mm long bristles areas under favourable seasonal moisture and lack of plant competition). in a single whorl. conditions. In the arid zone, it has In fragmented landscapes, small or spread extensively during infrequent Other native grasses with spike-like narrow remnants of native vegetation episodes when summer rainfall was heads include annual and perennial are more vulnerable to buffel grass well above average for several years. nine-awn grasses or bottle-washers invasion than larger patches with an This has been documented in the (Enneapogon species), smaller grasses intact canopy. Ashburton River catchment in WA, that have florets crowned with a ring from 1978 to 2002. Native plant communities invaded of nine hairy awns. by buffel grass include: Where it grows • Poplar box (Eucalyptus populnea) and How it spreads silver-leaved ironbark (E. melanophloia) Buffel grass is native to Africa, the woodlands in Queensland. Buffel grass has been spread throughout Middle East and Asia and naturalised the dry tropics, subtropics and arid • Mountain coolabah (Eucalyptus elsewhere, including the USA and lands of the world by human activities. orgadophila) woodlands Mexico where it is planted for cattle It is thought to have been introduced in Queensland. pasture. In Arizona it invades fire- inadvertently to Australia in the 1870s • Brigalow (Acacia harpophylla sensitive plant communities and the in camel harness from western Asia. dominant and subdominant) listed increased risk of fire poses a threat Camel trains were major means of as Endangered under the Environ- to the distinctive Saguaro cactus transport through inland Australia ment Protection and Biodiversity communities. and it is likely that buffel grass became Conservation Act 1999 (EPBC Act).

Weed Management Guide • Buffel grass – Cenchrus ciliaris 5

• Gidyea / gidgee (Acacia cambagei) Potential distribution identical to the main cultivars are shrublands in central west Queensland. naturalised in central Australia. Forms • Riparian and floodplain woodlands Buffel grass is still spreading within other than registered cultivars may have throughout the semi-arid and arid and between regions, unassisted and been introduced to the region or new zones, eg river red gum (Eucalyptus through planting. Modelling based types may be arising in the field. camaldulensis) and teatree (Melaleuca on climatic and soil requirements has Research is also underway into breeding species) woodlands on ephemeral predicted that 25% of Australia is new types to extend its use as pasture rivers in central Australia. potentially ‘highly suitable and 43% in heavier soils and cooler regions. New suitable for buffel grass growth’. • Vegetation on alluvial plains and forms of buffel grass may have potential other sites of relatively fertile soils Extensive areas were mapped as to invade a wider range of habitats. in central Australia (eg Acacia suitable or highly suitable, where There is inherent uncertainty in predicting woodlands and ghost gum (Corymbia buffel grass has not yet been recorded the potential limits of distribution due aparrerinja) and bloodwood or records are sparse. These included to the wide range of conditions in which (Corymbia opaca) open woodlands). northern SA and adjoining areas. buffel grass already occurs; imprecise • Coastal vegetation and islands off Soil and climate data were classified knowledge of the current range, genetic the Pilbara coast (Western Australia), at a broad scale for the continental variation, breeding system and ecology

riparian zones and wetlands, alluvial mapping. Modelling at finer spatial of naturalised populations; and the Buffel grass plains; tussock grasslands, eucalypt scales is needed to predict with unknown effects of factors such as woodlands, chenopod shrublands more certainty where areas of high future land management changes, and overgrazed hummock grasslands. biodiversity value are under threat. cultivar development programs and • Mulga (Acacia aneura) open / Mapping of current buffel grass long-term climatic variation. – Cenchrus ciliaris woodlands and shrublands are distribution is largely based on sometimes invaded at sites of higher accumulated records, particularly Growth cycle moisture and soil fertility. herbarium specimens, though the Buffel grass is summer-active. • Dry rainforest or ‘softwood scrub’ collection of such records has not been Established plants can respond rapidly remnants dominated by species such comprehensive in space or time. Field to small rains in spring to autumn but as bottle tree Brachychiton rupestris, surveys are needed to determine how make little growth during winter in the belah Casuarina cristata, vines etc accurately existing records represent inland non-tropics. Seeds germinate can be invaded along edges adjacent the current limits of distribution. to pasture if burnt, including semi- rapidly, but will not germinate on light Genetic studies suggest that forms evergreen vine-thickets listed as falls of rain. Generally, at least 20–25 mm of buffel grass that are not genetically Endangered under the EPBC Act. of rain is required for germination and establishment, as buffel grass seeds need to be moist for about 3–5 days in order to germinate. Plants can germinate from seed, mature and flower within 6 weeks of a significant rainfall event.

Buffel grass seed may survive for up to an estimated 4 years in the soil, but plants can live for many years (possibly up to about 20 years). In drier locations, moisture levels sufficient for high seed production, or for widespread germination and plant establishment, may occur infrequently. The variable climate may result in a dynamic distribution of buffel grass across the landscape, with drier sites being

Buffel grass (Cenchrus ciliaris) infestation on calcareous loamy soil along a creek in Karijini NP, WA. recolonised from moist refuges after Photo: S. van Leeuwen prolonged drought.

Weed Management Guide • Buffel grass – Cenchrus ciliaris Buffel grass – Cenchrus ciliaris • is needed. to biodiversity, arangeofstrategies minimise existingandpotentialthreats scale are yettobedeveloped.To abundance ofbuffel grassonabroad that wouldsignificantlyreduce the intervention. Managementoptions its furtherspread through early is limited,itmaybefeasibletocontain range. Inregions where itsdistribution spread within andbeyonditscurrent There is potentialforbuffel grassto it todoabout What Photo: R.Davies Buffel grass( be neededtoprevent further spread slashing operations. Strategieswill assisted byroad gradingand into susceptiblehabitatsisprobably distance dispersalalongroadsides grass isjuststartingtoinvade. Long biodiversity andareas where buffel These includesitesofsignificancefor should beidentifiedacross theregion. Priority areas forcontrol measures management includingweedcontrol. co-ordinated approach tovegetation to resolve policyissuesandenablea ecosystems. Processes are needed and amajorweedofnative buffel grass isbothapasture plant Regional planning: Cenchrus ciliaris Weed aaeetGuide• Management in manyregions, ) burnt buttsresprouting) burnt aftersummerrain.Uluru,NT. • • monitored andcolonising plants buffel grassseedlings.It shouldbe vegetation provides competitionto dispersal. Abuffer zonewithintact to minimiseseedproduction and pasture, grazingneedstobemanaged To containbuffel grasswithin the is atriskfrom buffel grassinvasion. vegetation adjacenttopastures Buffel grasspastures: herbicides aftersignificantrainfall. with control measures suchas opportunity totargetfresh regrowth old buffel grassfoliage,there isan at risk.Where fire hasremoved where other valueswouldnotbe grazed toreduce buffel grassbiomass grass mayneedtobeslashedor wildfires. Areas dominatedbybuffel prevent more frequent, extensive species. Strategiesare neededto and flameheight,damagingwoody also increase localisedfire intensity grass undertrees andshrubscan threaten biodiversity. Clumpsofbuffel frequency and/orintensity, which can fuelfires ofincreased extent, after favourableseasonalconditions Fire: infrastructure corridors. along andfrom roadsides andother the rapidbuild-upofbuffel grass Buffel 6 native rs – grass ecrsciliaris Cenchrus be neededatthistime. cover issparse.Mostresources will conditions orfire whenotherground rainfall, especiallyfollowingdrought soon afteradequatewarmseason Spread ismostlikely dispersal patterns. seedling establishmentandlocal conditions thattriggerabundant requires understandinglocalseasonal the speciesisabsentorsparse.This control buffel grassinlocationswhere priority shouldbetomonitorand At regional andlocallevels,ahigh spreading Prevent buffel grass • • • and methodsforrehabilitation. There pioneerspecies are alternative and becomeanon-goingfuelhazard. vegetation structure inthelongterm species, prevent recovery ofcomplex persists andmayexcludeotherplant once buffel grassisestablished,it Soil stabilisation/rehabilitation: biodiversity valuesunderthreat. andthe grass distributionpatterns adequate knowledgeaboutbuffel approach isoftentoacquire The firststepinplanningsuchan and plantcommunityrestoration. habitat quality, ecosystemprocesses adverse impactsonfire regime, its furtherspread whilemitigating management isneededtominimise biodiversity conservation.Strategic semi-arid areas ofhighvaluefor significant weedinmanyaridand buffel grassiseasilythemost Areas managedforconservation: to setseedfollowingrainfall. from grazingtoallownativegrasses term. Paddocksneedtobespelled to maintainplantdiversityinthelong pastoral andconservationpurposes buffel grass: Native rangelandscontaining open themuptobuffel grassinvasion. vegetation remnants astheycan prevented from escapingintonative removed. Fires inpastures shouldbe it isbeneficialforboth Buffel grass – Cenchrus ciliaris before before to maximise . In weed management by treating buffel buffel by treating from adjacent lands into from tackling more infested areas. areas. infested tackling more not that activities do Ensure areas the seeds into clean spread cover. or disturb native ground Adapt to local seasonal conditions seedlings maturing to prevent and seeding. Follow up previously in areas grass regrowth moving to new before treated of infestation. areas Seek mechanisms for managing spread areas. or treated weed-free avoid damage to native vegetation. to native vegetation. avoid damage disposal of Plan appropriate weed material. to Plan a rapid response seasonal changes activities. of control the effectiveness from the grass Remove buffel least infested areas and adapt the plan accordingly • • Include monitoring of native plant regeneration is often a tendency there programs of weeds to focus on the removal as a goal, but at the site level the of native ultimate goal is restoration vegetation. It is important to monitor and native plant regeneration appropriately. respond • • 4. Monitor and evaluate outcomes 3. Implement the action plan 3. Implement the action Control methods difficult grass plants are buffel Mature to kill because they have a tough base system and regrow and extensive root after cutting, grazing or burning. only is effective Herbicide treatment foliage. In arid or on actively growing the period of active semi-arid regions may be short and unpredictable. growth can shield growing Old, dry growth contact with herbicide and leaves from a single application may not be sufficient to kill the plant. Spot spraying or grubbing individual tussocks minimises Cenchrus ciliaris : indicate for control for control identify high risk 7 . The area and priorities for each buffel grass for each buffel vegetation first and consider the fauna and flora needs of rare infestations core plants towards to downslope. based on the site information. Define priority areas grass by overlaying maps of buffel native vegetation, site density, values and risks. Plan to weed strategically buffel grass density across the site; grass density across buffel of seed identify major sources can occur. which re-invasion from Map native vegetation condition: assess its capacity for recovery and grass is removed after buffel identify sites of high biodiversity values, such as habitats of rare flora and fauna. and risks: Values and other factors. sites for erosion Identify goals – the better quality native protect – grass isolated buffel work from – upslope plants from control in stages Work Include control of other weeds so that they do not establish where grass has been removed. buffel Select the most suitable control method to stage in each area growth Map weed infestations: • • • • • • targeted at each stage should be of a manageable size so that thorough follow up is possible. • • • 2. Develop the site action plan Management Guide • Buffel grass – Weed Weed weed management plan are: Weed from the least weed-infested bush towards weed-dominated areas towards the least weed-infested bush from Weed Native vegetation Weeds Identify native plants (including grasses) and weeds. patches of buffel grass patches of buffel moving to uninfested areas. seeds develop • – slash into rather than away from – clean vehicles and clothing before slashing and road grading: slashing and road – slash before possible, where infestations before they seed. infestations before Particular vigilance is needed along such as roadsides dispersal routes and drainage lines. Strategicvegetation native weeding in Steps to develop and implement a long-term Where buffel grass occurs in native buffel Where vegetation a planned, strategic that, is essential to ensure approach grass is replaced buffel after treatment, by desirable plant cover rather than seedlings or grass regrowth, buffel other weeds. Sites of high biodiversity value should be identified and targeted first. As well as information on buffel methods, grass biology and control a plan should be based on specific knowledge about the site, including the distribution of other major weeds. assessment of the need It requires following removal for revegetation grass. of buffel 1. Investigate the site Reduce established infestations • Practise weed hygiene during • small, isolated Locate and remove Buffel grass – Cenchrus ciliaris tailored toyour situation. of NationalSignificance andAlertListspecies.TheIntroductory Weed ManagementManual (alsoavailablefrom thiswebsite) may Refer totheCRCfor AustralianWeed Managementwebsite (www.weeds.crc.org.au) forweed managementguidesinthisseries,as we working onbuffel grass. Consult yourlocalnaturalresource managementorganisationorcounciltofindlocalcontactsonmanaging weedsforbiodiversit and territory, includingminorusepermits. Authority (APVMA).TheAPVMAwebsite hoststhePUBCRISdatabasewhichcontainsinformationonallherbicidesthat are registere Contact detailsforstateandterritoryagencies withresponsibility forweeds are listedabove,alongwiththe AustralianPest undertaken whenthegrowth rateis To beeffective, sprayingshouldbe Foliar spray and forseedlings. weeks afterraintocheckforregrowth seeding ifpossible.Followupwithin 30 cmacross. Removetheweedsbefore deep roots. Thebuttcanbemore than plants haveaverytoughcrown and from keysites,butmature buffel grass Small, isolatedplantscanbedugout or sparseinfestations Physical removal ofsmall production insomeregions. but existingorganismsaffect seed biological control isnotanoption, grass isavaluableforagespecies, may bemosteffective. Becausebuffel of physicalandchemicaltreatments significant, lastingimpact.Acombination combined withothermethodstohave buffel grassandslashingneedstobe removal favoursre-establishment of to otherspecies.Large-scalemechanical chemical wastageandriskofdamage Contacts Australia- Territory State / wide NSW WA Qld NT SA Weed Department ofAgriculture andFood Australian PesticidesandVeterinary Department ofNaturalResources, Environment Protection Authority Department ofPrimaryIndustries Department ofEnvironment and Department ofWater, Land and Medicines Authority(APVMA) Department ofEnvironment Environment andtheArts Biodiversity Conservation Management Guide • Buffel grass – – grass Guide•Buffel Management and Conservation Climate Change Department Photo: D.Butler further invasion. damaged thetree canopy, promoting 5 yearsafterahotfire fuelledbybuffel grass The edgeofMazeppaNP, centralQueensland the sameorothertreatment methods. growth. Followupisessentialusing Persistent dryfoliagemayshieldfresh knapsack) toavoidoff-target damage. equipment (handgunandhoseor short. Spotsprayusinghand-held when conditionsare suitablemaybe green foliage aspossible.Theperiod and theherbicideappliedtoasmuch high (leavesare brightgreen andglossy), Fax: (02)62724753 (08) 89992020 (02) 62725852 (08) 93340333 (08) 93683333 (08) 83039620 1800 680244 1300 130372 EPA Hotline 131 555 Phone 8 [email protected] [email protected] [email protected] [email protected] Customer servicecentre [email protected] [email protected] [email protected] Email N/a ecrsciliaris Cenchrus Photo: D.Butler in MazeppaNP, centralQueensland. Buffel grassinvasionofintactgidgee/brigalow seedlings whenactivelygrowing. grubbing ofsurvivingplantsand Follow upwithfurthersprayingor to protect thesoilfrom erosive rainfall. to leaveslashedmaterialontheground be veryeffective. Itmaybedesirable by sprayingaftereffective rainfallcan Initial slashingofoldfoliagefollowed extensive infestations Combined treatment of icides andVeterinary Medicines http://services.apvma.gov.au/ www.nationalparks.nsw.gov. www.nt.gov.au/nreta/natres/ au/npws.nsf/Content/Weeds www.dpi.nsw.gov.au/weeds y, includingcommunitygroups assistindeveloping aplan www.dwlbc.sa.gov.au www.agric.wa.gov.au www.naturebase.net/ www.epa.qld.gov.au www.apvma.gov.au d ineachAustralianstate weeds/index.html PubcrisWebClient ll asguidesforWeeds Website 9 ...case study Success managing buffel grass at Alice Springs Desert Park

Alice Springs Desert Park introduces visitors to central Australia’s diversity of habitats, plants and animals and to cultural knowledge and use of the environment. The exhibits and infrastructure occupy a core area of 54 hectares within a wider park area of 1300 hectares of natural vegetation, extensively invaded by buffel grass. The park is situated on the lower slopes of the MacDonnell Ranges and the adjacent plain. Throughout the district, buffel grass typically dominates such habitats, where it has largely replaced native grasses and other herbaceous plants. Buffel grass A buffel grass control program has been conducted in the park since its inception in 1996. The first goal was to eradicate it from the core area, to – Cenchrus ciliaris enable visitors to see and understand Chipping individual buffel grass (Cenchrus ciliaris) tussocks in Alice Springs Desert Park, NT. Photo: G. Dinham more of the native ecosystem. A further goal is to reduce the level of buffel grass fuel in the wider park area to a transformation from an understorey on relatively flat ground being slashed reduce the risk to biodiversity assets consisting almost entirely of buffel grass by machinery. Whipper snippers were and infrastructure from wildfire. to a remarkable diversity of native used around the base of trees and grasses and other herbaceous plants, shrubs. Where possible, the slashing Early control methods employed in occurring through natural regeneration. was timed to prevent seed set and the the core area included grubbing out These results suggest that even where viable seedbank is expected to diminish individual plants and following up with buffel grass has become dominant, over time. There has been little recent herbicide spot spraying whenever green native plants persist in the seedbank for buffel grass seedling recruitment due shoots appeared after rain. The project a number of years and can germinate to dry conditions. is labour intensive and much assistance readily after rain, once the weed is has been received from volunteers and The slashing has been successful in removed. Some resilience of the native community work programs. Follow-up reducing fuel loads and the threat of understorey is not unexpected, given work could be needed more than once wild fire. The reduction in the amount its adaptation to long periods of little a year, but the number of work hours of buffel grass has allowed native plants rain, but the maximum longevity of the decreased greatly over the first two to grow between the slashed clumps. native seedbank is not known. Much years, both in dense and light Slashing has been followed up with of the spread of buffel grass in central infestations. A large proportion of the spot spraying and grubbing. Slashed Australia has occurred in the past core area has now been cleared of clumps are easier to grub when dry four decades. buffel grass, in spite of unusually wet and easier to spray after rain events. conditions in 2000 and 2001 which Ongoing monitoring will be needed The park managers emphasise that there delayed this achievement. to prevent buffel grass reinvasion of is no point to any treatment unless you the core area, especially where soil is At the start of the program, it was have the capacity to do the follow-up disturbed or native understorey is very not known whether removal of buffel spraying after rain events as the buffel sparse. Since 2005 buffel grass in the grass could be achieved. Also unknown grass will return and you will have wider park has been sprayed or chipped was the likely vegetation response to wasted your time. at strategic locations, with larger areas its removal. In fact, there has been case study

Weed Management Guide • Buffel grass – Cenchrus ciliaris Buffel grass – Cenchrus ciliaris Herbicideshouldbeappliedtoas • Theplants’conditionatthetime • seedlings andregrowth. Theseinclude: are critical tosuccessfulcontrol ofboth have indicatedthatarangeoffactors both grass-selectiveandnon-selective, crop situations withsystemicherbicides, Trials tocontrol buffel grassinnon- and regrowth. applied toactivelygrowing foliage been effective onbuffel grasswhen formulated foraquaticsituationshas plants andgrasses.Glyphosateherbicide chemical andaffects bothbroad-leaved Glyphosate isanon-residual, systemic the relevant permitforeachstate. Medicines Authoritywebsiteincludes Australian PesticidesandVeterinary NSW, Queensland,SAandWA. The in somenon-crop situationsexistin perennial grasseswithglyphosate environmental weeds,including Permits thatincludetreatment of not includedontheapproved label. for apurposeorinmannerthatis allow registered products tobeused chemical product’ maybeissuedto to allowminoruseofanAGVET crop situationsinAustralia.A‘Permit controlling buffel grassonlyincertain chemicals, are registered onlabelsfor Herbicides, includinggrass-selective Herbicides spraying maybe mosteffective. combines slashing followedby repeated treatment. Treatment that may beunavoidable,necessitating Reduced contactinthesprayshadow This isbestachievedbyspotspraying. much ofthegreen leafaspossible. summer rain. sufficiently developedafterheavy same timewhenseedlingsare mature plantsandseedlingsatthe be possibletospraybothresprouting not beseeding.Iftimedwell,itmay and maybefloweringbutshould growing withnosignofsenescence effectiveness. Theymustbeactively of treatment willdetermineits Weed aaeetGuide• Management not carryherbicideintowaterways. taken toensure thatrainfallrunoff will herbicides. Particularcare shouldbe preparation anduseofthechosen training inthesafestorage,handling, carefully. Operatorsshouldhaveformal the labelandfollowinstructions When usingherbicides,alwaysread grass atlowdensity. Perseverance isvitaltomaintainbuffel treatment effectiveness attimes. in seasonalconditionsmayreduce rainfall events.Unpredictable variation to eachsituationandresponsive to program shouldbecarefully tailored planning isneeded.Atreatment To address thesecriticalfactors,forward Followuptreatment, usingthesame • Anassessmentshouldbemadeof • C. pennisetiformis Buffel grasses ( Legislation hedgehog grass. be knownasinnocent weedor gentle Annie).Thesespeciesmay also and synonym (Mossman Rivergrass); (fine-bristled burrgrass); C. biflorus in oneormore Australianstatesare: Cenchrus it creates. environment andthefire hazard USA, duetothethreat tothe prohibited noxiousweedinArizona, weeds legislation.Buffel grassisa not proclaimed underanyAustralian and toseedlings. applied toactivelygrowing plants or different methods, shouldbe control program. during different phasesofthe selective herbicidesmaybesuitable situations, grass-selectiveandnon- minimise off-target damage.Insome to different herbicides inorder to native plantsandtheirsusceptibility C. longispinus C. pauciflorus species thatare declared (Gallon’s curse); 10 Buffel Cenchrus ciliaris and (spiny burrgrassor (spiny burrgrass); C. setiger C. incertus C. echinatus rs – grass C. brownii , ) are , ecrsciliaris Cenchrus Photo: M.Robertson Buffel grass( extensive roots. .Brigalow( 1. by buffel grassare listedasendangered: three ecological communitiesthreatened Under theCommonwealthEPBCAct, biogeographic regions ofthestate. weeds intwoofthefourmajor report amongthetop fiveenvironmental the 2007StateofEnvironment In WA, buffel grasswasidentifiedin one ofthespeciesspecialconcern. Act1995 Conservation under theNSW listed asakeythreatening process by exoticperennial grasseshasbeen Invasion ofnativeplantcommunities .Bluegrass( 3. Semi-evergreen vinethicketsofthe 2. a majorissuefor landmanagers. areas where itdominatesisbecoming grass invasionandrehabilitating key land. Containingunwantedbuffel reserve, Aboriginallandorvacantcrown grass ispastoralleasehold,conservation of thearea underthreat from buffel permission wouldberequired. Much South AustraliathePastoralBoard’s agencies.However,government in has beenwidelyencouragedbysome non-native speciestopastoralleases on leaseholdland.Introduction of as clearancebutmayberegulated in nativevegetationmaynotbedefined Sowing ofnon-nativepasture species of improved pastures isnowregulated. native vegetationforestablishment In mostofAustraliatheclearance Nandewar Bioregions Brigalow Belt(NorthandSouth) dominant andco-dominant) Belt Bioregions (NorthandSouth). dominant grasslandsoftheBrigalow Cenchrus ciliaris Acacia harpophylla Dichanthium Threatened Species . Buffel grassis ) plantshave species) 11

Dixon, I. R., Dixon, K. W. and Barrett M. (2002). Eradication of buffel grass (Cenchrus ciliaris) on Airlie Island, Pilbara Coast, Western Australia. In Veitch, C.R. and Clout, M.N. (eds.) Turning the tide: the eradication of invasive species. IUCN SSC Invasive Species Specialist Group. IUCN, Gland, Switzerland and Cambridge, UK. Pp 92-101. http://www.issg.org/database/species/ reference_files/TURTID/Dixon.pdf

Environment Protection Authority (2007). State of the Environment Report. Western Australia 2007. http://www.soe.wa.gov.au/report/ A drainage line in buffel grass (Cenchrus ciliaris) pasture on heavy clay alluvium near Springsure, biodiversity/weeds central Queensland. Photo: D. Butler Friedel, M., Puckey, H., O’Malley, C., Buffel grass Waycott, M., Smyth, A., Miller, G. Knowledge gaps Acknowledgments (June 2006). Buffel grass: both friend and foe. An evaluation of the Relatively few resources have been Information and guide revision:

advantages and disadvantages of – Cenchrus ciliaris directed at assessing the long-term M. Friedel, CSIRO; D. Butler, Qld buffel grass use, and recommendations consequences for biodiversity, EPA; S. van Leeuwen, WA DEC; for future research. A report to the pastoralism and the human population J. Virtue, SA DWLBC; D. Agnew, Desert Knowledge Cooperative from buffel grass invasion of vast SA Arid Lands NRMB. Research Centre on the dispersal, areas of Australia. Maps of current Map: Australia’s Virtual Herbarium, impact and management of buffel distribution often lack sufficient (Cenchrus ciliaris), via Royal Botanic grass (Cenchrus ciliaris) in desert detail for planning local or regional Gardens Melbourne, Council of Heads Australia. http://www.desertknowledge management. Knowledge of the of Australian Herbaria. www.rbg.vic. crc.com.au/publications/downloads/ long-term sustainability of buffel grass gov.au/cgi-bin/avhpublic/avh.cgi. DKCRC-Report-17-Buffel-Grass.pdf pastures in various climates and soils Greenfield, B. (2007). SA Arid Lands is lacking. Where buffel grass is already Case study: G. Dinham, Alice Springs buffel grass management plan, DRAFT. widely established, methods to Desert Park. South Australian Arid Lands Natural minimise its spread, and to maintain Resource Management Board. diversity of native understorey and References and further overstorey plant species and vegetation information Harden, G. (1993). Flora of NSW. structure, are required. In vegetation Volume 4. NSW University Press. where buffel grass is dominant, the Clayton, W.D., Harman, K.T. and Humphreys, L. R. (1967). Buffel grass nature of its impacts on native fauna Williamson, H. (2006 onwards). (Cenchrus ciliaris) in Australia. Tropical (including invertebrates) and on soil GrassBase – The Online World Grass Grasslands 1:123-134. nutrient cycles is largely unknown. Flora. http://www.kew.org/data/grasses- Its potential distributional limits and db.html [accessed 08 November 2006; Lawson, B.E., Bryant, M.J. and Franks, the susceptibility of various native 15:30 GMT]. A.J. (2004). Assessing the potential vegetation types to invasion under Cook, B.G., Pengelly, B.C., Brown, S.D., distribution of buffel grass (Cenchrus specific management regimes and Donnelly, J.L., Eagles, D.A., Franco, M.A., ciliaris L.) in Australia using a climate–soil future climate change are poorly Hanson, J., Mullen, B.F., Partridge, I.J., model. Plant Protection Quarterly understood. Peters, M. and Schultze-Kraft, R. (2005). 19(4):155-163. The possibility that buffel grass Tropical Forages: an interactive selection roots exude chemicals that inhibit tool. CSIRO, DPI&F(Qld), CIAT and ILRI, growth of other plant species needs Brisbane, Australia. to be investigated. www.tropicalforages.info/

Weed Management Guide • Buffel grass – Cenchrus ciliaris Quick reference guide

Regional / local status of buffel grass Not yet established Small, isolated outbreaks Widely established Management Prevent establishment Eradicate Contain infestations and mitigate threat goals Strategies Maintain native vegetation Physical removal or Native vegetation: required cover and integrity herbicide, or combined Identify high priority biodiversity assets under threat from Regulate planting—define treatment buffel grass and protect them through implementing long- term site management plans zones at greatest risk Follow up is essential Practise weed hygiene Native / buffel pasture: Prevent re-establishment Manage grazing and fire to maintain diversity, eg allow native Monitor, detect and identify or invasion by other weeds plants to recruit seedlings and set seed in good seasons new infestations especially through passive or active Cleared / improved pasture: drainage lines, floodouts, site restoration calcareous rises, roadsides Manage seed production and minimise spread into adjacent and bare soil areas areas, remove seedlings from outside planted area. Prevent fires spreading from pastures. Where rainfall is variable, extra vigilance will be needed Roadsides and other infrastructure corridors: during a sequence of wetter Map infestations, practise weed hygiene and remove new than average summers outbreaks to prevent spread – Cenchrus ciliaris

Apply herbicides during increase their effectiveness and minimise periods of active growth off-target damage.

Buffel grass Buffel Herbicide should only be applied when Prevent buffel grass plants are green, leafy and actively re-establishment growing, generally soon after significant warm season rainfall. In semi-arid and Once mature plants have been arid climates, the period when spraying killed, the focus is on preventing can be effective may be quite limited. re-establishment from seeds in the soil Buffel grass (Cenchrus ciliaris) along the Plan ahead to take advantage of these seedbank or brought in by wind, water highway near the Flinders Ranges, SA. times. Follow instructions on the or animals. Buffel grass seeds may Photo: D. Powell herbicide labels. retain viability for up to 4 years or so and young plants can set seeds in their seedlings before they establish deep Follow up first season of growth. roots and produce seed. 1. Identify patterns of invasion and 3. Restore ground-cover vegetation It is essential to follow up physical dispersal agents and manage major to areas from which buffel grass or chemical treatment after the next seed sources. Slashing can be done has been removed. significant rainfall. This will require at any time but, if undertaken before 4. Avoid large-scale disturbance that advance resource planning. Spot spray seed set, it will minimise additions would create extensive areas of regrowth from butts while still growing. to the buffel grass seedbank. bare soil and favour buffel grass Consider both physical and chemical 2. Monitor weed-free areas after wet invasion, such as too-frequent fire treatments as combining them may seasons to detect and remove or overgrazing.

Disclaimer While every care is taken to ensure the accuracy of the information in this publication, the CRC for Australian Weed Management takes no responsibility for its contents, or for any loss, damage or consequence for any person or body relying on the information, or for any error or omission in this publication.