MLSN Guidelines to Analyse Soil Tests

For decades, the conventional guidelines for analysing soil test data used by the turf industry worldwide have not changed too much.

The common methods used in Australia have been Sustainable Level of Available Nutrition (SLAN) and Base Cation Saturation Ratio (BCSR). In 2012, turfgrass research scientists based in Thailand and the USA, Dr Micah Woods and Dr Larry Stowell, brought their skills and historical data together to question these traditional guidelines and their relevance in turf today. The result of their studies was a new set of guidelines, called the Minimum Levels for Sustainable Nutrition (MLSN).

Living Turf Technical Agronomist, David Worrad, and the technical team have been looking at the MLSN Guidelines for since 2016 and have found that these guidelines make sense with a lot of what we actually see when analysing soil tests in Australia. It quickly became hard to ignore these new guidelines when comparing soil tests interpretation and making nutritional choices.

 When compared to the traditional guidelines, the MLSN Guidelines are a more financially and environmentally responsible method for analysing soil test data. To bring the MLSN Guidelines to the Australian turf market, Living Turf brought Dr Micah Woods (Chief Scientist at the Asian Turfgrass Center and Co-Developer of the MLSN Guidelines) to Australia in 2017 to speak to turf managers on the practical implications of applying these guidelines to their soil test results.

The Living Turf Team supported Micah to speak at seminars in Sydney, Adelaide and Brisbane. With over 200 delegates attending these seminars, Micah thoroughly captivated the audience describing why he believes “the conventional guidelines are broken”. He clearly described how the MLSN Guidelines were developed using thousands of soil tests and how further validated using the global soil survey, forming the basis of what professional turf managers consider “good turf”.  In essence, this acknowledges the art, skill and knowledge of turf managers worldwide.

 The seminars generated huge interest and engaging conversations. Highly respected turf managers, from both the older generation and the new, commented that the MLSN guidelines and what Micah described made sense to them based on their own observations. Many Australian turf managers are now working with the Living Turf Technical Services to analyse their own soil tests using the MLSN guidelines.

 The MLSN numbers are designed as a minimum level to maintain; these numbers were set slightly higher than the actual minimums found in the research to act as a bit of a buffer. If the amount of nitrogen that is to be applied over a given period of time can be estimated, then using a simple calculation, the amount of each nutrient that will be used by the turf can be calculated. Once this is understood, then the amount of each nutrient that is required to be applied as fertiliser can be accurately calculated.

Cool and warm season turf grasses use nitrogen and other nutrients in different ratios, so it is important to take these variations into account when calculating nutrition requirements.

Living Turf introduced the MLSN soil testing guidelines to the Australian turf industry and uses these in the Turf Forensics® tools. Living Turf Technical Representatives use these tools to work with customers to help them to understand their turf’s nutritional requirements more accurately so that they can apply fertiliser in a more responsible manner both financially and environmentally.