This project is the latest extension to a long-term study that has the overall objective of determining the impact of high residue, crop rotation and minimal disturbance no-till systems on soil quality as well as crop water use efficiency, yield and the economics of the various treatments. In addition to gathering further data, this project will place greater emphasis on interpretation of the complex, long-term, interactions that are becoming evident in this long-running systems trial.

New information will be generated on:

1. Yield and gross margins of 9-12 years of continuous wheat compared with more diverse rotations;
2. Impact of rainfall/seasonal changes on profitability of continuous wheat;
3. Changes in soil organic carbon under no-and seasonal impacts on soil organic carbon levels;
4. Effectiveness of fallow in conserving soil water and nitrogen;
5. Impact of summer rainfall on in-crop mineralisation and soil water storage;
6. Impact of plant residue levels on crop growth, soil water storage and evaporation;
7. changes in weeds, insects and diseases; and

8. Effect of windrow burning on soil chemistry and weed populations.

   The project aims to increase our knowledge and provide management options in a no-tillage cropping system.