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||ililflil]ilil b cAia. _ _ o17os3 ilst FQRt0Aft il1?053 ;?:,iJ:ilIii*.*s'*sTr* l- l-r\llDl,lAlll'CiIMENT TABLE OF CONTENTS \tiii:iifi:;i:|\i hUlj iLrriiJA Page SIJMMARY I. LIST OF PARTICIPANTS ii. ACKNOWLEDGMENTS ii. 1. INTRODUCTION 1 2. OBJECTIVES 2. 3. METHODS 2. 3.1 LiteratureSurvey J. 3.2 InterviewProcess J. 3.3 Field Survey J. 3.4 AdditionalSurveys 6. 4. RESULTS 6. 4.1 Definitionof a GrassyWoodland 6. 4.2 GrassyWoodlands in the WesternAustralian Wheatbelt 7. 4.3 Deciineof GrassyWoodlands 8. 4.4 The lnterviewProcess 8. 4.5 Field Survey 9. 4 .5 . 1 Descriptionof EstablishedGrassy Woodland Site 10. 4.5 .2 Flora on EstablishedGrassy Woodland Sites t7. 4.5.3 SpeciesAbundance on EstablishedGrassy Woodland Sites t7. 5. DISCUSSION 20. 6. RECOMMENDATIONS FOR FURTHER RESEARCH .A 7. BIBLIOGRAPHY 26. APPENDICES Survey Form and List of Respondents List of GrassyWoodland SitesIdentified GrassyWoodland Monitoring Data PhotographicRecords of the Field Sites Vascular Plant Speciesof GrassyWoodlands Distribution of Plant SpeciesRecorded in GrassyWoodlands SpeciesRecorded From Plots in Order of DecreasingFrequency Known lncations of Themedatriandra Q. australis) from the WAHERB Specimen Database. TABLES 1: List of EstablishedGrassy Woodland Sites Summaryof SpeciesRichness and Cover Resultson the ten GrassyWoodland Sites J: Comparisonof generarepresented tn Eucalyptusloxophleba Woodlands in 1906 and 1995. FIGURS,S Administrative Regionsof the Deparnnentof Conservationand Land Management 2: Natural Regionsadapted from Beards1990 3: Locationof StudyArea Map showingpositiors of sitesGWl andGW2 5: Map showingpositions of sites GW3 and GW4 6: Map showingpositions of sitesGW5 i: Map showingpositions of sitesGW6 8: Map showingpositions of sites GW7 9: Map showingpositions of sites GW8 10: Map showingpositions of sites GW9 l1: Map showingpositions of sitesGW10 STJMMARY Temperategrasslands are amongstthe most threatenedecosystems in Australia due to widespreadagricultural deveiopment(Lunt 1995). These grasslandshave been dramaticallyaltered and are poorly representedil conservationreserves (Lunt 1990). This report reviews Grassywoodlands in WesternAustralia and as such forms part of a wider studyon thesecommunities in Australia. The south-westof Western Australia was previously covered with large areas of woodlandssuch as York Gum-Jamand SalmonGum. Thesewere often found on the heavierfertile soils of the valleys which were seiectivelycleared for agriculture. The aim of this project was to determinethe existence,previous and current extent of Grassywoodlands, and though selectedfield trials establishthe compositionof these communitiesin the Wheatbeltof WesternAustralia. It wasdetermined from histodcalrecords that grasslandsand grassy woodiands were a part of the early vegetationof the WesternAustralia. Recordsof early settlersat the Swanconstantly referred to the open,parklike appearanceof the country with scattered ffees and grassy ground layer. The literature indicated that these communities, particularly the York Gum-JamGrassy woodiandswere subjectedto frequent fire regimes from the Aborigiml population prior to Europeansettlement. There were several critical consequencesof settlementfor theseplant communities, namely the disruptionof the native burningpattems, increased grazing by introducedanimals and widespreadclearing. Field surveysundertaken to documentthe flora speciescomposition of theseGrassy woodlandsdefined two main types,these were - York Gum (Eucalyptustoxophteba)- Jam (Acacia acuminata)Woodland and Open Woodlandsof mixed Eucalypts (Eucatyptuswandoo, Eucalyptw capillosa andEucalypus salmonophloia).One other 'granite type of communitywas described- the meadow',this was comprisedof grassesand herbs with a few (lessthan 5%) shrubsusually of Acaciasp. on shallow soils over granite,in associationwith graniteoutcrops. The ten sitessampled were domhatedby the native grusesNeurachne alopecuroidea, Stipa trichoplrylla, the herb Borya sphaerocephalaand the low sedgeLoxocarya cinerea. The herbs and forbes dominatedthe speciescomposition. The speciescomposition of the Grassywoodlands sampled in 1995is consideredlikely to be representativeof the earlierexamples of this vegetation.However, historical descriptiorssuggest that changedgrazing and fire regimeshave resulted in a reduction of the role of grassspecies in the understoreycomposition of this vegetation. A series of recommendatiorxsummarising further researchneeds, monitoring and conservationneeds of theseareas have been suggested. ll. LIST OF PARTICIPANTS Project Coordination: Dr Libby Mattiske, Principal Researchand Reporting: Ms DeniseTrue, SeniorBiologist Field Assistance: Ms CathyGodden, Biologist Mr Andrew Johnston,Biologist Plant Identifications: Dr Eleanor Bennett,Principal Bot'nist ACKNOWLEDGMENTS The authorswould like to gratefully acknowledgeall of the peoplewho participatedin the interview process.Particular thenks go to the following peoplewho openly helped in expandingthe coverageof this project through their knowledgeand experience- AngasHopkhs, Mike Fitzgeraldand Lyn A&ins. Specialthanks to David Mitchell for valuablecomments during the report editing stages. Thanls also go to l,ouise Gilfedderand Jamie Kirkpatrick (Iasmania)for their patience in answering my many questions regarding Grasslands and Grassy Woodland conservationand for the organisationof the field excursion. This project was funded by the Australian Nature ConservationAgency National Biodiversity ConservationPrograrn under the GrasslandsEcology Program - 1993/94 @roject No. G008) l. 1. INTRODUCTION Temperategrasslands are amongstthe mostthreatened ecosystems in Australia due to widespreadagriculnral development(hmt, 1995).Theyhave been dramatically altered and are poorly representedin conservationreserves. Vegetation in the Western Australian Wheatbelt has been cleared extensively for agriculturalpurposes in lesstban 100 years. The Wheatbeltof WesternAustralia was previouslycovered with large areasof woodlandssuch as York Gum-Jamand Salmon Gum. They were often found on the heavier fertile soils of the valleys which were selectivelycleared for agriculture. After extensiveclearing for agriculture, there were few remnantsof thesewoodlands lg6nining in the Wheatbelt. Due to their open Mture, their relatively high nutrient status and the levels of disturbance,most of these remnantshave been invaded by introduced grassesand other weeds. Thus, there a very few examples of these woodlandswhich remain in their original conditionand retainthe original understorey. The remaining remnants are under continuing pressure,and hence location and documentation of these renurants are crucial in order to develop appropriate managementto eDsuretheir persistence. In WestemAustralia" many vegetationand floristic studieshave been undertakenon sandplaincommunities in the Wheatbelt(Pate and Beard 1984; Griffrn er al. 1985; Brown 1989); however, there is little inforrnation on the biology, ecology and disbibutionofthe oncewidespread woodland communities. Recently the C.S.I.R.O.have undertakenstudies in this areawith an investigationinto regenerationof SalmonGum (Eucalyptuss almonophlo ia) communities. Remnantvegetation surveys have beenundertaken in many areasof the Wheatbelt. Thesesurveys have included documentation on the vegetationtypes, the conditionof the vegetation,vegetation maps and dishibution maps of theseremnants. However the only sourceof systematicvegetation classification and distribution in the Wheatbeltis the broad scalevegetation mapping by Beard (1972-1980).An investigationas to the "grassy existenceand dishibution ofremaining woodlands"has not beenundertaken, and much land clearinghas occured sincethe dateofthose surveys. OBJECTTVES The objectivesof the project were: . Review the literature on grassywoodlands. Interview specialistsin the field on the conceptand potential locations and condition of grassywoodlands in WestemAustralia. Identify good quality, undisturbedYork-gum, Jam wattle and other Grassy Woodland remnantsin the Wheatbelt basedon information available in the scientific literatureand suppliedby specialistsin the field. Survey a selectionof the identified sites to documentthe (presumed)original flora speciescomposition ofthese grassy woodlands. Preparea final report giving details of the remnantsand providing a basis for frrther research,monitoring andconservation ofthese areas. METHODS 3.1 Literature Survey A numberof publishedand unpublishedrepods were reviewed (seeBibliography) to clariff a definition of grassywoodlands itr WesternAusralia and to provide previously identified examplesof grassywoodlands in WesternAustralia. The literature review was used to locate previous studiesthat provided information on the previous and current distribution, compositionand statusof gmssywoodlands in the Wheatbeltof WesternAustralia. Secondlythe review was usedto list people with expertisein this researcharea for participation in the interview process. This aspect of the review enabled the compilationof a target list of researchersand other peoplewith expertiseand possible knowledgeof sites of grassywoodlands h WesternAustralia used in the interview process. 3. 3.2 Interview Process A list of potential intervieweeswas compiled from the review and from personal recommendations.An interview guide describingthe project and a survey form were then developed.Initial contactwith intervieweeswas madeby phoneand survey forms were then either sentout or a follow-up interview made in person. The survey form and interviews