A: Based on my own research and discussions I have had with other researchers, the most important factor to stress regarding the use of soil health assessment methods is that just as soil fertility assessments need to be correlated with local soil type, management practices, and climate regime, so too do soil health assessments.
This may mean one soil health test is better at identifying differences in soil management practices and soil conditions while another method is more appropriate to use in other locations. This is similar to the use of Mehlich 3 for P analyses in neutral-to-acid soils and Olsen for P assessments in more basic soils.
— Barbara Bellows, Tarleton State University, Stephenville, Texas
A: Does the Haney test tell us how much nitrogen (N), phosphorus (P) or potassium (K) our soils can provide so that we can use it to cut fertilizer rates? And if it does, is there a written manual that tells us how to interpret the results?
— Tim Stensland, Badger, Iowa
A: It would be good to understand when are taxa-specific tests such as the PFLA test of more value than the simple “Are the microbes there or not?” tests like Solvita? When is it worth the extra cost?
Also, as we move into the topic of feeding soil biology, many in the biology arena make the same nutritional mistake that conventional ag has made. There is little emphasis on micronutrients, and an assumption that when you fix pH, biology and the like, necessary amounts of cobalt, molybdenum and other essential microelements will just appear.
Furthermore, there is little research in terms of micronutrients that beneficial soil microbes may need. How are microbial nutritional needs being integrated into interpretation of soil biology tests?
— Mary Lucero, End-O-Fite Enterprises, Valdo, N.M.
A: Information gap: The calibration of the test results with various inputs that can affect the soil health tests and profitability of the cropping system is less than desired in many cases.
— Mark Alley, Alley Agronomics, Blacksburg, Va.
A: First, I have trouble understanding the benefits of any of these health tests. Second, how do these tests equate to more yield, increase in carbon in the soil or profit for the farmer? And lastly, with the information we get from the test, what do we need to do to implement these benefits on our farms?
— George Holsapple, Jewett, Ill.
A: I feel the average farmer needs more direction on determining which soil test is best for their operation, what the advantages are, understanding the differences in the in-field soil sampling process (such as depth, timing), ability of local vendors in producing accurate and consistent soil test analysis, and the associated costs of each.
— Randy Van Matre, NRCS, Rockport, Ind.
A: Most growers use conventional soil tests. As growers eliminate tillage and plant cover crops, their organic matter increases and soil biology improves over time.
A test that indicates that a grower can reduce N, P and K is needed. None of the existing tests do that job. Perhaps soil texture is a factor that is not being considered?
— Dan Towery, Lafayette, Ind.
A: What would be helpful is numbers or ranges that correspond to where we are, and a range of inputs we may/should need to apply. You may need some caveats to reflect rainfall amounts.
I put 55-110 units of N on my corn that is no-tilled into a cereal rye, crimson clover, etc. cover and you could tell no difference. I got 5 inches of rain in 3 days after applying my fertilizer, so it appears it all left.
— Bill Harned, Lebanon Junction, Ky.
A: I’d like to see a test that monitors how soils come to life as seasonal changes affect their processes. Do “soil-like” inoculants, liquors show quicker soil health effects?
These tools are valuable to crop scouts who will calibrate their eyes and skill to monitor progress, as well as for spot calibration against measured soil carbon inventory to better scout spatial rates of change in soil health.
— Neil Havermale, Red Hen Systems, Fort Collins, Colo.
A: Solvita measuring CO2 informs farmers their soil has something alive, but not the quality of the rhizosphere population. It’s the most economical and has practical applications. The Haney test has the most promise. Researchers will need to give farmers valid, actionable recommendations for their soils. The expense of the tests will need to be lowered too.
— Jimmy Kinder, Walters, Okla.