DELIVERING ENHANCED AGRONOMIC STRATEGIES FOR IMPROVED CROP PERFORMANCE ON WATER REPELLENT SOILS IN WESTERN AUSTRALIA

Funded by:                                           GRDC

Participating groups:                          SEPWA, Southern DIRT, West Midlands and Mingenew-Irwin

Project duration:                                  5 years (2014 – 2018)

Research advisor:                               Stephen Davies, DAFWA

Summary

Soil water repellence results in poor and variable water infiltration, incomplete wetting of soils and patchy and delayed crop, pasture and weed emergence. Soil water repellence significantly reduces crop and pasture productivity and typically results in (1) very inefficient use of soil water and nutrients, (2) poor weed control and (3) increased wind erosion risk. Nearly 3.3M hectares of Western Australia’s agricultural soils are at either affected by or at high risk of soil water repellence with a further 6.9M hectares at moderate risk. Estimates by the WA Department of Agriculture and Food suggest the opportunity cost from lost production due to water repellence is of the order of $250-330M per annum.

This project will provide opportunities to further enhance and refine management options for non-wetting soils; a particular benefit for Southern DIRT is that it will also provide a greater focus on water repellence on forest gravels in high rainfall south-west agricultural region. Understanding soil water repellence across a range of affected WA soil types and developing management options best suited to these soil types is a key aim of this project.

Together with other key grower groups including South East Premium Wheat Association (SEPWA), Mingenew-Irwin Group (MIG) and West Midlands Group (WMG), Southern DIRT will be supporting the field research, delivery and extension of project activities and will be providing important monitoring and evaluation feedback. Southern DIRT members will also be hosts to a number of demonstration sites which have been implemented this season, which will further address the need to be developing management options which are locally relevant.