1. The Ecology & Management of Serrated Tussock in Native Pastures Warwick Badgery & David Kemp The University of Sydney Orange

2. Background Grasslands with a high perennial grass density and high DM can limit serrated tussock invasion Flupropanate kills many native grasses and creates bare ground for serrated tussock to invade A system is needed that focuses on prevention of seedling recruitment and in many cases on selective control of adult plants

3. Seedling reinvasion after spraying Bare ground left after spraying native pastures

4. 0.00.51.01.52.02.5 DM (t / ha) 0 5 10 15 20 25 Seedlings / 25 cm 2 Serrated tussock seedlings cannot establish where pasture cover and DM are high Grigulis unpublished

5. A perennial grass dominated patch that has prevented invasion The paddock on the left has prevented invasion with no control despite large seed inputs

6. Survey Objectives To determine farmers current management of serrated tussock To assess their knowledge and use of preventative treatments –grazing management, fertiliser, pasture establishment To assess whether their management is proactive or reactive To define the on-farm limitations to better management –money, landscape, knowledge, attitude.

8. The Survey Farms were selected at random within the serrated tussock area mapped in 1997 54 farmers surveyed –personal interviews on the farm

9. Mean Property Conditions Average size:1546 ha Average rainfall:680 mm Soil Types Basalt15 % Granite44 % Shale34 % Loams/Alluvial soils7 % Topography Accessible73 % Inaccessible27 % Pastures Sown34 % Native53 % Degraded13 % Heavy (>50% of a paddock), Medium (5-50% of a paddock) Scattered (isolated plants)

10. How To Define Successful Managers? Identify properties that have successfully controlled serrated tussock under difficult conditions –Difficult conditions: present for >20 years, and on neighboring properties Identify factors associated with successful management: –Physical: property conditions –Management: actions & attitude

11. Classifying Properties

12. Characteristics of Successful Properties ResponseSuccessfulOther Cooma Region (%)71.4 ± 18.425.5 ± 6.4 Average Rainfall (mm)593 ± 48.4693 ± 15.1 Shale Soils (%)1.7 ± 1.737.2 ± 5.5 Accessible Area (%)91.7 ± 5.070.6 ± 3.9 SR below normal (%)55.3 ± 14.324.9 ± 3.8 Feed Livestock (%)57.1 ± 20.288.6 ± 4.8 Steers (%)28.7 ± 15.05.9 ± 2.3

13. Characteristics of Successful Properties Pasture management very important No serrated tussock control practices were found to be different Prevention is better than cure

14. Preventative Management A high awareness of key principles: –87% were aware that serrated tussock seedlings would not establish where ground cover is high A willingness to change management: –71% said they would reduce grazing pressure to limit serrated tussock invasion Very few actually make changes

15. Why Wont Farmers Change? Preventing plants is not as visually obvious as killing them with a herbicide Therefore management tends to be reactive rather than proactive

16. Grazing Management 81% of people used a set stocked system Most rested some paddocks at times –rests may be too short or not often enough? The obstacles to using more active grazing management were: –drought –cost of locking up country –fencing needed

17. Changing Farm Structure Control of serrated tussock is difficult under current farm structures –paddocks can’t be rested for long enough to let desirable grasses become competitive –difficult to take paddocks out of use to rehabilitate them –difficult to improve ground cover in autumn

18. Property Structure

19. Management Change Change structure: 1.decrease the number of mobs / combine mobs 2.subdivide paddocks if needed Less mobs that are larger means: –easier to budget feed and adjust stocking rates –paddocks are rested more often and for longer –it is possible to manage for herbage mass to increase plant competition for tussock seedlings –better utilisation of forage –can see the feed available more readily –stock will be moved more often

20. What Do We Do with Areas Already Heavily Infested? Arable and reasonable soil fertility: –Sowing an introduced perennial pasture is successful Non-arable, & / or low soil fertility & / or low rainfall –Currently no reliable long- term control –Flupropanate used every 3 to 5 years –New answers needed!

21. New Research Three aims: 1.To determine the levels of competition required to prevent serrated tussock invading in different areas of the landscape (i.e. ridge tops v lower slopes) and environments (i.e. low rainfall) 2.To establish perennial vegetation on difficult sites following serrated tussock control to prevent reinvasion (i.e. native grasses that are adapted to low fertility) 3.To find management techniques to weaken adult serrated tussock plants, to make them more susceptible to competition Funded

22. Conclusion Continual effort is needed to keep serrated tussock under control –use plant competition to limit seedling establishment –spot spray adult plants The longer the rest period the easier it is to manage for pasture cover / competition –reduce mob numbers and improve rotations Decisions need to be made early in a drought –to avoid over-grazing / killing useful competitive grasses New research –aimed at managing serrated tussock in areas where we don’t yet have effective long-term control