1. GRASSY RECONSTRUCTION: A Plant Competition Trial and insights into the relative competitiveness of two Cumberland Plain grass species

2. Some Challenges in Reconstructing Grassy Habitats Seed supply Seed establishment knowledge Weed control Ecological approaches to weed control Managing for diversity and weed resistance

3. A Plant Competition Trial: -Trial Overview-

4. Monocultures & Mixtures

5. Species Selection & Location rationale for sites & species

6. Bulking-up Seed for Trial

7. Trial planting in 1996

8. Trail Measurements

9. An Early Hypothesis Mixtures would be more productive (and therefore weed resistant) than monocultures; due to resource partitioning, mutualism, and diversity of growth habits and requirements

10. Some Microlaena & Chloris Results

15. Observations: Mic. & Chloris Mic. inferior competitor early and therefore more productive in monoculture than in mixture Chloris stronger competitor early and performing well in mixture and monoculture Chloris very productive early (good early cover) By 2004 Mic. is the stronger competitor and is displacing Chloris Mic. monocultures are the superior treatments with highest cover scores in 2004 Chloris loosing productivity over time Mic. gaining productivity over time

16. Hypothesis Outcome In many circumstances (time of sampling, species make-up in treatment, etc) monocultures were more productive (not expected) A new observation: slower growing species better competitors in the longer term

17. Consistent with Ecological Theory of Tillman: At moderate to low mortality rates, transient dominance is predicted whereby species may actually be replaced by slower growing species with lower resource requirements

18. Strategies & Implications of Results Seeding of monoculture mosaics may be more suitable than blended mixes in some circumstances (for some species) Some species will perform better in blends Inclusion of slower growing & longer lived species is important Quick growing species such as Chloris may be a useful cover & nurse crop for slower growing species Slower growing species may be best sown into alternative seed beds (not cultivated) such as into a native cover crop or into sprayed down exotic cover

19. Herbicide & Sowing Rate Trials

20. Application of trial results to seed production & rehab. areas

21. Reconstruction can be successful; success requires… Reliable seed supply from local or regional sources Ongoing improvements in establishment knowledge, including weed control Careful consideration of genetic & provenance policies in the context of fostering seed supply sufficient to meet the need