Farm Table says:
This Fact Sheet was produced by NSW DPI in 2010 aims to assist grain growers and their advisors to work through the considerations to make decisions about the use of recycled organics in grain cropping systems.
A framework for working through these considerations is presented with each component discussed.
The key sections include:
- Identifying production constraints and plant nutrition needs – The first step when considering the need for any input to a grain cropping system is to identify the constraints (chemical, physical or biological) to the production system
- Physical and chemical properties of manures and recycled organics – The quality of manures can vary considerably and is influenced by a number of factors
- What is the likely nutrient contribution from manures or organic wastes?
- How much of the nitrogen is likely to be available to the crop?
- How much of the phosphorus is likely to be available to the crop?
- What are the likely agronomic benefits from applying manures?
- What are the other benefits?
- Are manures cost-effective?
- What are the risks?
In conclusion, the non-fertiliser benefits from recycled organics and manures are all directly or indirectly related to the organic matter and carbon they contain, which may improve soil physical properties, such as structure, infiltration, water holding capacity and porosity.
However, end-users should be aware that benefits may not become apparent until several years after application and that cost-effectiveness will be site specific. However, over time, manures and recycled organics can play a role in improving soil quality and crop productivity.