Value of feedlot manure as a soil organic amendment

Summary

​The use of feedlot and other manures in broadacre farming has traditionally been based on their potential to provide an alternative and cost-effective source of nutrients to conventional fertilisers. Recently, there has been growing interest in these products for their potential to provide long term increases in soil organic matter.
The choice of both product and application rate is generally based on cost of product ($/tonne) or cost of nutrient ($/kg), without any real consideration of the physical, microbial and chemical benefits the product can provide. However, it is important that choice of product and application rate take into account economic, agronomic and environmental benefits, as these products are highly variable and can cause unforeseen consequences with long term applications.
This project was set up to utilise field trials to examine the effect of long term applications of feedlot manure and other manure/soil amendment products on a range of soil parameters, including nutrient and organic matter levels, microbial activity and physical structure. The economic value of these attributes was also to be evaluated, so feedlot manure could be valued for the physical, microbial and chemical benefits it provides, not just $/kg of nutrient, when applied as a soil amendment in broadacre farming systems. However, the project was terminated in March 2013 when the principal researcher resigned from the company, and the company indicated it did not wish to proceed with the project. The project was subsequently re-instated with the principal researcher who now operates as a private consultant. The new project code is B.FLT.0382, and the project is due for completion in 2018.