Farm Table says:
A guide to fertilisers and soil treatments for beef and sheep meat production systems
What is the problem?
There is a strong interest among livestock producers in the efficacy of soil treatments that provide a possible alternative to single superphosphate. In line with these changes in market sentiment, there has appeared a large range of soil and pasture treatments available for use by livestock producers.
What did the research involve?
- at Wongwibinda, there were three application rates of compost and three application rates of superphosphate and these were matched for cost per hectare. Treatment application rates at Armidale were set so that all treatments had the same cost
- superphosphate was applied annually at the rate of 125 kg/ha at Holbrook, Tenterfield and Binalong and at 320 kg/ha at Armidale. At Wongwibinda, superphosphate was applied annually at 130, 260 and 520 kg/ha
What were the key findings?
- the Holbrook site had a history of superphosphate application and at the start of the trial had Olsen P = 21
- olsen P levels were significantly increased above the untreated control in response to superphosphate (14 mg/kg increase) and CalSap (7 mg/kg increase; composed of 30-60% calcium carboxylate, 17% potassium, applied at 20L/ha, Optima Agriculture), whereas plant available sulphur (S) was significantly increased by superphosphate (17 mg/kg increase) and NutriSoil LS (7 mg/kg increase; nutrient and microbial mixture, content not provided, 5L/ha applied twice annually, NutriSoil)
- the Wongwibinda site did not have a history of super phosphate application and at the start of the trial had Olsen P = 8.3 mg/kg, KCl40-S = 8.5 mg/kg, Colwell K = 215 mg/kg, organic carbon = 1.9%, pHCaCl2 = 4.9
- the Armidale site did not have a history of super phosphate application and at the start of the trial had Olsen P = 8.9 mg/kg, KCl40-S = 9.2 mg/kg, Colwell K = 300 mg/kg, organic carbon = 3.6%, pHCaCl2 = 4.8
- the Tenterfield site has yet to provide a Final Report on the consequence for soil fertility and pasture production from the application of a wide range of soil treatments
These projects, with the addition of another, supported by Binalong Landcare and NSW Department of Primary Industries, formed the basis of Section 1 of this report and were used to provide an across-project assessment of the efficacy and cost effectiveness of alternative soil treatments for improving the biology and productivity of soils, pasture and livestock.