MONITORING WEED
GulfSavannahNatural ResourceManagement (GSNRM)contains:
CapeYork
EinasleighUpland
GulfPlains
WetTropicsbioregions
Gilbert,Mitchell,Norman andStaatenRiver Catchments
TheRegionis DominatedBy:
TropicalSavannah Rangelands 200kmofcoastlineinthe GulfofCarpentaria
STEP 1
During2024,GSNRMconductedsixworkshopsacrosstheregionto showcasetheprojecttolocallandholders
Eachparticipantwasgivenfive,A3sizepropertymaps,overlainwith 100 hahexagons,whichdiffersfromthecurrentQueenslandWeedDistribution datawhichuses 1700hasquares
STEP 2
Ofthe175landholderswecommunicatedwith,44wereunabletofully participateduetovariedreasons
ItisnoteworthythattheregionwasimpactedbyCycloneJasperwhenthis projectcommenced,withunprecedentedrainfall,floodingandthehighest 24-hourtotalrainfall(975mm)everreliablymeasuredinAustralia
STEP 3
131individualpropertymapsweredistributedinperson,electronicallyor viapost,spanning~887millionha
Participantsusedadensitymappingguide(Figure1)andscoredthe presenceofuptofivetoppriorityplantsofconcernacrosstheirproperty, witheachmapdedicatedtoonespeciesonly
100hawasthesmallestreportableinfestationsize
PLANT SPECIES
BetweenMarch2024andApril2025,52%ofthemaps werereturnedby68landholders,covering2.96 millionha
36plantspeciesweremapped Themostfrequently reportedplantsbyareaarelistedinFigure2 Categorically,shrubswerethemostcommon(16spp), followedbytrees(9spp),grasses(4spp),herbs(3 spp.),sedges(2spp.)andonevinespecies.Onetree stillremainsunidentified,buthasbeententatively labelledSingleThornPricklyBush(Dichrostachys spicata) Additionally,tenCategory3Restricted InvasivePlantsundertheBiosecurityAct2014were reported.
Thenumberofspeciesrecordedbylandholdersin eachcatchmentcanbeviewedinFigure3.The higherreportingratefromGilbertoncatchment (Etheridgeshire)maybeexplainedbythefactthat(1) 85%oftheGSNRMregion’spopulationresidesinthis location,and(2)GSNRMhasastrongerhistoryof communityengagementwiththiscatchment’sarea OUTCOMES
Infestationsofcategorythreerestrictedinvasive speciesthatareanextensiontotheirmappedrange andadditionaltotheQueenslandSpatialCatalogue (28/10/2024)areChineeapple(Ziziphusmauritiana)31,983ha(Etheridgeshire)andPricklyAcacia (Vachellianilotica)-2,999ha(Carpentariashire) GSNRMwillprioritisecontrolworkinthisareainthe futureasfundsbecomeavailable
Datapointsanddensityscoresrecordedinthisproject willbesharedwithLocal,StateandRegional organisations,suchasFarNorthQueenslandRegional Councilstosupportplanningandfuturemanagement actions
Gradergrass (Themedaquadrivalvis) 202,047ha
NativeHeartLeafPoisonBush (Gastrolobiumgrandiflorum) wasnotedduetoitstoxic effectonstock
Breadfruit(Gardeniavilhelmii), Conkerberry(Carissalanceolata& Covata),Rubbervine(Cryptostegia grandiflora)SoapbushandTurpentine (Acaciaholosericea&Achisholmii) wereraisedduetotheircontributionto woodythickeningandsubsequent impactsonpastoralproduction
Accidentalintroductionofweed specieswasraisedthrough contaminatedhaybales turf andtransitingmachinery (externallyowned)
Horehound (Mesosphaerumsuavelons) 94,158ha
Breadfruit (Gardeniavilhelmii) 64,685ha
Figure2:MostFrequentlyReportedPlantsbyarea
Figure3: PlantSpeciesbyCatchment