Q&A: Lawrence Mayhew

April 19, 2017
Soil Health brought to you by EarthWorks Supplier News Turf
With regard to humic inputs and turf maintenance, how do they compare, or differ, from more traditional fertilizers?
In general, many turf inputs are simple linear compounds similar to high-input soluble synthetic conventional agricultural fertilizers, but humic products provide the opportunity to increase the complexity of fertilizers to better provide the atmosphere and diversity needed for geo-microbiological soil interactions that release plant nutrients, rather than relying on high input rates. Not many companies have the knowledge to put together ingredients that provide diversity required by the soil microbiome because many of the components are extremely complex and can be incompatible when mixed. Ionic chemistry, which relies on hydrophilic interactions of cations and anions, just doesn't apply to these products because their biochemistry is governed mainly by covalent bonding under hydrophobic conditions that are conducive to microbiological interactions, and humics are amphoteric substances, meaning that they react as either acids or bases, depending on many conditions.

How long have they been available as a nutritional tool to the turf maintenance market?
I don't know. My first exposure to humics in turf was at the golf superintendents conference in Atlanta about 14 years ago. At that time, humates were illegal to use in most states, but the turf industry was obviously way ahead of agriculture at that time. Humates have been used extensively in dry land agriculture in Australia for as long as anyone can remember where the money spent of fertilizers has to be extended as far as possible on broad acre farms of 20,000 acres and up.

How do humic substances work in a soil system to benefit turf?
Better nitrogen utilization, releases tie-up phosphates, improves the bioavailability of potassium and micronutrients, allowing for reduced application rates of inputs.

What should a superintendent look for when purchasing a humic input for his turf?
I do not recommend using humics as "stand alone" products. They are best used blended with fertilizers at the time of manufacture. That means the end-user must trust the manufacturer has made the right choices. Manufactures who have joined the Humic Products Trade Association pledge that their product claims are based on legitimate scientific research, and the humate ingredients in their products have been analyzed by using the HPTA certified method of analysis, which is the only scientifically validated analytical procedure for humic acids and fulvic acids. HPTA provides member companies logos that can be used on their labels to support their claims (see attached).

Are there environmental issues that need to be considered when incorporating humic substances into a soil system or making it a part of a turf nutrition program?
That is the big question that comes up when applying for listing any product with the Organic Material Review Institute (OMRI), a non-profit that reviews materials for compliance with the USDA National Organic Program (NOP) and Canadian organic standards. Numerous humic products have been reviewed by OMRI as well as USDA certifiers, legitimate products have always been approved. Humic products are also used for environmental reclamation, including reclaiming ammunition manufacturing sites that are contaminated with nitrates and they are very effective in products used to clean up oil spills.

Would humic substances be considered “organic” products?
The word "organic" has been used for centuries to signify the branch of chemistry that studies carbon-based substances. However, for the purpose of marketing, use of the word "organic" in the context of fertilizers, food, and fiber is codified in Federal Rules CFR 7, §205 National Organic Program (NOP). Humic acids and fulvic acids are listed in the NOP rules as organically approved materials, provided they meet all the evaluation criteria of CFR 7 § 205.600, which are quite stringent. You just can't say your product is organic, it must meet the criteria to make that claim.

Are there misconceptions in the marketplace about integrating humic substances into your turf nutrition program? What are they and why are they incorrect?
There is a lot of chest beating...my humic product is better than theirs... and there are many claims that a product contains incredibly high content of humic or fulvic acids. Claims need to be supported by scientific proof, one way to do that is through the HPTA membership program as mentioned above. HPTA members cooperate with each other and bring integrity into the market place with legitimate claims backed by science. For example, the term fulvic acids has no regulatory basis. The current validated analytical method developed by HPTA only analyzes for hydrophobic fulvic acids, which is an official regulatory term in the US. Hydrophobic fulvic acids are the most biologically active form of fulvic substances, and have been shown to increase root mass and many other benefits. Beware of anyone claiming they have fulvic acid, it can be anything if it wasn't analyzed by the HPTA method.

If superintendent are looking for more information about the role of humic substances in soil systems, where would you direct them to go?
The Humic Products Trade Association website at humictrade.org