Over the past five years considerable research has been undertaken assessing options for water repellent sands but less has been done for the gravel soils. The aim of this research is to look at soil water repellence management options for sandy gravel soils over a four year period (until December 2018). This research consisted of on-farm strip trials comprised of five different treatments for water repellence (Control, Paired row, minimal disturbance and two types of wetting agents) in combination with two cultivation treatments (modified one-way plough or no plough). The first year study showed that the adoption of a strategic tillage practice (one-way plough) provided a significant improvement in terms of crop establishment and grain yields on a moderately repellent sandy gravel.
One-off soil inversion and deep soil mixing can ameliorate repellent soils, incorporate nutrients and remove some compaction. Trials to date have shown benefits in crop productivity and yield but a more detailed understanding of the changes in soil properties and crop performance over time is required to better understand the drivers of changes in productivity and implications of buried topsoil. This trial was located in Badgingarra on pale, yellow and deep water repellent sand.
This report outlines results obtained from soil and plant sampling in 2015 and 2016 and gives an overall analysis of the changes in soil fertility factors with time.The trial was designed to determine the long term effects of 1980 P treatments on soil fertility and was conducted in Badgingarra on deep, grey over pale yellow sand.