By Kate Raston
20 February 2014
The valuable lessons of 24 Wheatbelt farming families working to improve the sustainability of their farms have now been put on paper.
The research varied from tackling wind erosion in Bodallin, comparing the efficacy of crushed limestone, lime sand and chalk lime at Kulin and investigating alternative fertiliser options at Quairading.
All research was the initiative of farmers who were faced with challenges replicated throughout the Wheatbelt and has now been documented in the “Soil Health Guide”.
Driving the trials has been natural resource management group Wheatbelt NRM. The group’s program manager for sustainable agriculture Dr Guy Boggs said $4 million had been spent over the past five years on these projects.
The funding had been sourced from the Australian government. “There are now more than 150 trial sites all over the Wheatbelt funded through the Soil Conservation Incentives Program,”
Dr Boggs said. “All of these projects focus on soils with poor health, they have few living organisms, show signs of soil erosion, crusting, and soil compaction.
“Eventually, poor soil health results in problems with crop establishment, root growth and crop yields and then increasing amounts of fertilisers, pesticides, and tillage are needed to maintain yields on poor quality soil.
“That is why it is so important to maintain high soil quality.” Part of the research identifies the ongoing problem of soil acidity, which the Department of Food and Agriculture WA last year estimated to be costing the WA farming community $498 million annually from lost production. Spreading lime has long been used as a management practice in tackling soil acidity, and one of the trials featured in the guide tested the efficacy of different liming products.
Kulin farmer Brian Bowey tested lime sand, crushed limestone and chalk lime sourced from different suppliers. “I was driven to conduct an independent trial as it’s hard to get decent, trustworthy results on lime products,” Brian Bowey said. The trial used strip tests of 100 tonnes of different lime products on a 100-hectare paddock, at varying rates from zero to 4t/ha.
Initial observations have found crushed limestone better on the loamy soil. “At this stage I believe 2t/ha of crushed limestone seems to offer the best value for money, plus the product is easier to handle,” Brian Bowey said. “The project has encouraged us to increase the liming program.”
While acidity was the focus for this Kulin farmer, wind erosion was the major challenge for landholders east of Merredin. The Bodallin Catchment Group designed a broadacre trial (10.5ha) that compared four farming practices including full stubble retention, cultivation, brown manuring and cover cropping and their effect on groundcover. After hearing about the project idea, South Moorine Rock grower Clint Della Bosca willingly offered his time, equipment and paddock.
The project began in 2010 and the initial results can now be found in the Soil Health Guide. “Being directly involved in the project allows for better understand of its findings,” Clint Della Bosca said. “Brown manuring will work, but timing is crucial. The earlier the better in my experience.”
The results from this trial and others are available in the Soil Health Guide, Available from the Wheatbelt NRM office on 9670 3100 or online at; http://www.wheatbeltnrm.org.au/resources/Soil-Health-Guide.pdf