BCSR a valid tool
SCIENTISTS JACQUELINE Rowarth (Rural News July 16) and Doug Edmeades (Rural News August 20) have criticised Albrecht’s base cation saturation ratio (BCSR) theory being used to make fertiliser recommendations.
AS A farmer with an interest in soil management I am always looking for information to deepen my understanding of how to best look after the soil on my farm.
Farmers are bombarded with conflicting information and advice. If the experts don’t agree, how are we to know what is best practice?
With a growing need to manage our soils and nutrients more sustainably, using the best combination of effective strategies to look after them must surely be a high priority. We are seeing in your newspaper claims and counter-claims regarding the validity of Albrecht’s BCSR theory as a basis for making soil fertiliser recommendations.
The current debate was sparked by an article by Jacqueline Rowarth and it includes two independent advisers, namely Robin Boom, who states he has been using BCSR for 23 years and has about 400 clients, and Dr Doug Edmeades, soil scientist and independent consultant.
Boom would like to see this put to scientific testing, whereas Edmeades says this would be a waste of money as there is such a large body of scientific work showing Albrecht’s theory is pseudo-science.
Surely it would be possible to survey a sample of their clients to ascertain if there are any significant differences in measurable outcomes from their respective practices. This could be achieved by taking a range of objective measurements and records from a sample of their client base using such criteria as: visual soil assessment (this has been underpinned by extensive research and the soil indicators are linked to economic, environmental and sustainability performance); production figures; profit; cost of production; quality of production/ animal health (eg, incidences of mastitis, somatic cell count, reproductive fertility, nitrate levels in milk, metabolic disorders, bloat); pasture quality and composition; fertiliser inputs.
With so much at stake, surely the potential benefit from getting to the bottom of this debate would be well worth the relatively small investment required to see if there are sound grounds to pursue more rigorous testing of BCSR in New Zealand.
Bruce Knight
Danniverke
Abridged: editor
• See pg 32 for more. Correspondence on this issue is now closed.
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