A guide to Alternative Fertilisers for beef and sheep meat production systems
| Project start date: | 11 March 2013 |
| Project end date: | 30 May 2014 |
| Project status: | Completed |
| Livestock species: | Grain-fed Cattle, Grass-fed Cattle, Sheep, Lamb |
| Relevant regions: | National |
|
Download Report
(0.7 MB)
|
|
Summary
There is strong interest among livestock producers in the effectiveness of soil treatments that provide a possible alternative to single super phosphate. There is a large range of soil treatments available for use by livestock producers, including animal wastes (e.g. cow, poultry, pig), composts, microbial products, microbial foods, plant growth substances and biologically activated phosphate rock. Research on the effect of these treatments on pasture production has been limited, which has hampered producer’s decision making process when it comes to choosing soil treatments and fertilisers.
MLA has supported several Producer Demonstration Site (PDS) projects to investigate the effects of alternative soil treatments on soil chemistry and biology and pasture and livestock production. This project used the results from those PDS’s 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.
From the PDS projects reviewed, the factor that best predicted pasture production in a phosphorous (P) limiting environment was the amount of P applied. Few other soil chemical or biological measures were regularly associated with changes in pasture production.
Objectives
The objective of this project was to review previous PDS projects to provide a test of soil treatments in P limiting and non-limiting environments. A total of 43 soil treatments were tested alone or in combination with superphosphate and these represented microbial products, plant growth or microbial foods, animal wastes, major or trace nutrients other than P, other forms of P and biologically activated rock phosphate.
Progress
With P limiting soils, soil treatments to provide P are most effective for increasing pasture production. Under these conditions, microbial products, plant growth or microbial foods or less limiting major or trace elements did not increase pasture production.
Pasture production was insensitive to the form of P and therefore animal wastes or other products capable of providing P were effective soil treatments in P limiting soils.
Measurements of microbial biomass and microbial activity were not associated with changes in pasture production and were highly variable over time. Where increases in microbial biomass and activity were detected, it was typically in response to soil treatments that provided plant limiting nutrients and not to substances which were promoted for microbial and plant growth or microbial foods.
The soil treatments with the lowest cost of producing extra pasture were those that addressed first limiting nutrients and in these projects, the most cost effective treatments were those that provided adequate amounts of P.
