IS OUR MANAGEMENT EFFECTIVE? THE RESULTS OF AN ADAPTIVE EXPERIMENTAL MANAGEMENT PROGRAM TO DETERMINE BEST PRACTICE CHEMICAL CONTROL ON CYTISUS SCOPARIUS AND IMPACTS ON NATIVE VEGETATION *Lynise Wearne Cathy Allan, Marie Keatley & Paula Dower Parks Victoria 1
Questioning Management Control undertaken without monitoring Unknown effectiveness, cost, off-target impacts AEM used to determine effectiveness of different control strategies simultaneously 2
Parks Victoria Weed Management Previously limited monitoring of weed control Cytisus scoparius largest weed program Test case to establish the use of an AEM approach 3
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Project aims To examine: efficiency (costs/benefits) of different strategies effectiveness reducing broom cover & abundance environmental outcomes vegetation species response And, to determine whether feasible to undertake AEM with internal Parks Victoria staff 5 resources
Best-practice herbicides Non-selective Biactive roundup - glyphosate - safe near water (autumn, spring) Selective Grazon - triclopyr, picloram (autumn, spring, irregular) Garlon - triclopyr without the residual picloram (spring) Autumn vs spring treatments, using label rates, of 1 ha plots at three replicated sites, including untreated 6 control plots
Treatments (1 hectare plots) Grazon Autumn Annual (GAA) X 3 sites Grazon Spring Annual (GSA) Grazon Irregular (GIAI) Biactive Autumn Annual (BAA) Biactive Spring Annual (BSA) Measurements within 60m x 20m Garlon Spring Annual (GRSA) Control (NT) 7
Parameters Measured Efficiency - Cost & time Herbicide & labour per 1 ha plot Time and resources for monitoring Effectiveness Photopoints Broom seedling density Broom cover, height, scorch and growth stage Environmental outcomes Ground cover Canopy tree condition Species richness & composition 8
Results environmental outcomes Parameters measured: Canopy species mortality Species richness Species composition 9
Canopy Species Mortality Significant higher mortality of adult Eucalypt trees: Bioactive and Grazon treatments Mean Percentage of dead Eucalypt adults (1200m2) 50 45 40 35 30 25 20 15 10 5 0 control BAA BSA GAA GSA GAI GLSA Treatment 2004 2006 Bioactive Grazon Garlon 10
Species richness and cover Total species richness (mean) and cover Weed vs Native species richness and cover Growth form (graminoid/herb/woody) species richness and cover 11
Species richness/ cover: graminoids Species richness % Cover M e a n s p. n o. ( + / - S E ) 5 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 NT BAA GAA GIA BSA GSA GarSA Treatment 70 60 50 40 30 20 aut 04 spr 04 10 spr 06 0 NT BAA GAA GIA BSA GSA GarSA Treat ment Decrease in richness and cover in non-selective herbicide (bioactive roundup) 12
Mean species no. (+/- SE) 8 7 6 5 4 3 2 1 Species richness/cover: herbacous & woody Species richness Herbacous Species aut 04 spr 04 spr 06 % cover (+/- SE) 60 50 40 30 20 10 % Cover aut 04 spr 04 spr 06 0 0 NT BAA GAA GIA BSA GSA GarSA NT BAA GAA GIA BSA GSA GarSA Treatment Treatm ent M e an s p ec ies n o. ( +/- SE) 2 1.8 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 Woody Species aut 04 spr 04 spr 06 % cover (+/- SE) 25 20 15 10 5 aut 04 spr 04 spr 06 0 NT BAA GAA GIA BSA GSA GarSA Treatment 0 NT BAA GAA GIA BSA GSA GarSA Treatm ent 13
Floristic Composition and key species changes MDS Analysis Floristic composition within treatments (between years) ANOSIM Analysis: significant differences between years SIMPER Analysis: key species changes 14
Floristic composition - NT 3D Stress: 0.19 2006 2004 year 2006 2004 ANOSIM analysis Differences between years (global r = 0.37, significance.01%) Differences between sites (global r = 0.58, significance.01%) 15
Floristic composition - GIA ANOSIM analysis 3D Stress: 0.18 year 06 04a 04s Differences between years (global r = 0.76, significance.01%) 2006 2004aut 2004spr Differences between sites (global r = 0.60, significance.01%) 16
Key species changes - GIA 3D Stress: 0.18 year 06 04a 04s 17
Floristic composition - BSA 2006 2004 3D Stress: 0.17 year 2006 2004s ANOSIM analysis Differences between years (global r = 0.54, significance.01%) Similar patterns to BAA Differences between sites (global r = 0.43, significance.01%) 18
Key species changes - BSA 3D Stress: 0.17 year 2006 2004s 19
Floristic composition - GarlonSA ANOSIM analysis 2D Stress: 0.17 year 06 04 Differences between years (global r = 0.79, significance.01%) 2006 2004 Differences between sites (global r = 0.61, significance.01%) 20
Key species changes Garlon SA 2D Stress: 0.17 year 06 04 21
Control 2004 2006 22
Grazon 2004 2006 23
Biactive roundup 2004 2006 24
Implications for management Significant off-target impacts: - loss of canopy species - loss of ground cover and species richness - alteration from herbacous to graminoid dominated Highlights the need to questions current weed management practices Environmental weed management needs to incorporate integrated management techniques Short experiment: what are the longer term implications? Alternative State 25
Thank you! Field data collection and analyses: Jodi Price, Caitlin Smith, Adam Whitchurch, Angie Ah Sam, Megan Underwood, Jen Lightfoot 26