On the verge of a new growing season, the “what’s new” in soil testing labs is the Solvita CO2-Burst test. Agronomist Bruce Weidner (Weidner Agronomy Services, Illinois) writes “the Solvita test is intriguing because of its potential to be more accurate than other tests, plus the fact that N management is key to my growers’ profits. This is a test that could set me & my business apart”. Bruce Hoskins, director of the University of Maine soil lab, said “Solvita may be the missing link in my nutrient management plan”. Tom Woodward, a soil consultant, working with Carl Stafford, Ag Extension agent, plan to correlate the Solvita field kit with Brookside Labs PMN test for nitrogen potential. Another leading national soil service, Midwest Labs, has launched “B.R.A.N” (Biological Respiration and Nitrification), a test based on Solvita. Several labs are abandoning the old procedure of calculating N-mineralization potential from the organic matter test – a procedure known to be inaccurate. Calibration trials evaluating the relationship of Solvita to the 7-day anaerobic N-min test show consistently high correlations.
Will Brinton, the inventor of the test, says “we are happy with this evaluation process… we see individual labs innovating around the test and seeking regionally appropriate linkages to reach their growers.” Solvita is unique since, unlike most soil tests, it is not a chemical extraction method. Soil microbes produce the test result – a burst of CO2 captured in a simple, overnight process. Enthusiasm is bolstered from reported high correlations observed of the Solvita test vs. actual nitrogen (and also phosphorus) mineralization from soil humus. “That’s free fertilizer” says USDA-ARS scientist Rick Haney, a soil-respiration pioneer who has coached Woods End on developing the CO2-burst as a test. By itself, the Solvita test serves as a biological indicator of soil health and, according to several NRCS sources, should qualify for cost sharing under EQIP in the Nutrient Management Code 590 category.
Solvita soil results from participating labs will be monitored in 2012 within the ALP Soil Proficiency program, and several NAPT labs are also offering Solvita. Speaking about the test, Bob Miller, technical director of ALP said, “The Solvita method is robust. It isn’t that soil respiration can’t be used to assess nitrogen-mineralization. It is just that we the labs haven’t used it in such a way.” Solvita is a new approach. Lowell Rheinheimer, farm resources manager for Organic Valley LLC, a large dairy farm coop, spoke about Solvita during a recent (Feb 2012) farm conference in La Crosse, Wisconsin: “perhaps 5% of people in this room realize how revolutionary this method really is”.