Soil Nutrient Management Project

Figure 1: From left to right Jeremy Casey, Neal Kinsey and Kim Solly. Photo courtesy of the NZ Dairy Exporter Magazine

Soil Nutrient Management Project

The project is focussed on the monitoring and scientific measurement of the changes which are occurring on two Methven dairy farms.

Methven dairy farmers Jeremy Casey and Kim Solly, had become interested in the Albrecht-Kinsey “biological” approach as a means of sustainably managing their newly-converted dairy farms. In the absence of information on the impacts of this system in the whole-farm context, they elected to manage only one of their pair of “matched” farms under the Albrecht-Kinsey (A-K) biological system, while continuing to manage the other farm according to conventional “good agricultural practice”.

They sought help with monitoring and evaluating the relative performance of the two systems. Since the concept had attracted significant interest among local farmers and the broader farming community, Jeremy and Kim considered it important to ensure that the evaluation was conducted according to acceptable research protocols, and that environmental, production and economic outcomes were appropriately monitored.

Soil nutrient management on each farm complied with the requirements of the relevant soil nutrient management system from the time the properties were purchased in 2011; pasture growth and composition had been monitored; and from the beginning of the 2013/14 season the herd was randomised across the two properties at the same stocking rate.

Farmers, rural professionals and scientists who want to understand the implications of adopting ‘biological’ fertiliser management strategies drive the project. Many of these approaches are promoted on the basis of research which is not supported by traditional scientists, and there is interest from all parties in collecting information that can be more readily understood.

Objectives

The project is a world-first, whole-farm evaluation of biological farming, and its use on dairy farms. Its objectives are:

• The provision of robust information on the potential farm-level impacts of “biological” soil nutrient management practices to provide a sound basis for decisions about changing soil nutrient management practices in order to meet the water quality limits required under the National Policy Statement on Freshwater Management and National Objectives Framework.

Click here to view the December field day presentation 2019

Click here to view the factsheet summarising seven years of Albrecht-Kinsey versus Conventional fertiliser

Key Findings

After 7 years (from 2012/2013 season) of alternate soil nutrient management and over 5 years of monitor pasture and animal production outcomes of the project show:

• • required greater fertiliser inputs and reached higher levels of Mg, K, S and Na but lower P in the soil.
  • did not alter soil physical characteristics but invertebrate numbers, especially earthworms, were higher.
  • applied on average 20% less N fertiliser and grew similar DM as the conventional farm
  • The A-K farm had higher clover content than the conventional farm – largely as a result of lower N fertiliser
  • had similar milk yield but frequently better animal health during spring and reproductive performance was often better
  • initially had higher costs but after four years both farms had similar financial performance
  • did not reduce estimated nitrate leaching (Overseer) or measured nitrate leaching risk (deep soil mineral N)

For further information about the project please contact: Racheal Bryant, Faculty of Agriculture and Life Science, Lincoln University. racheal.bryant@lincoln.ac.nz