Carp, kelp and Christmas Island; where to next with fertilisers?

The Carp, kelp and Christmas Island; where to next with fertilisers? project evaluated the performance of selected fertiliser alternatives, relative to both single superphosphate to assess their impact on soil chemical, biological and physical properties, subsequent pasture growth, composition and quality and animal performance.

Summary

This PDS project evaluated the performance of selected fertiliser alternatives, relative to both single superphosphate to assess their impact on soil chemical, biological and physical properties, subsequent pasture growth, composition and quality and animal performance. The PDS found most of the alternatives examined in this field study supplied little or none of the three major nutrients, phosphorus, nitrogen or sulphur. In terms of the dry matter production, feed quality, and composition of the field trial pasture, none of the alternatives, nor indeed single superphosphate, had any impact on these parameters over the three seasons of evaluation. The alternatives also had no effect on soil chemical and microbiological properties at the field trial site over the three years, or on the physical softness of surface soils in the winter of 2011.

The extension of the demonstration by two additional growing seasons showed no cumulative effects on pasture growth for any treatment.
Soil sampling from 2013 and 2014 highlighted methodological challenges in the 2013 data due to changes in funding intervals and consequent storage conditions. However, the additional two years of data showed a net importation of nutrients onto the site via the grazing method used, and no further conclusions could be drawn about trends in the soil phosphorus concentrations.

In summary, there were no measured production or economic benefits gained from the application of alternative products to a typical Holbrook pasture and soil type for the six seasons of the demonstration.

When: 2009 to 2014

Contact: Jeff Hirth and the Holbrook Landcare Network

More information

For more information, please read the final report summary and download the final report of the initial PDS (B.PDS.0003) (PDF, 1.4 MB)  and the extension (E.PDS.1412) (PDF, 2.9 MB) from the Meat & Livestock Australia website.