What is in this article?:
- New soil test tracks microbial activity
- How it works
Rick Haney thinks it is time to shoot for realistic yield goals, not maximum goals. A new online tool from the Grassland, Soil and Water Research Laboratory is designed to help. The Soil Nutrient Assessment Program (SNAP) utilizes current fertilizer prices, soil test results, input recommendations and crop-based county averages for the past 15 years to predict the chance of making yield goal.
"With SNAP, we can quickly evaluate the cost and likely benefit of additional inputs," says Haney.
How it works
His test attempts to measure activity, food source and the balance of the two, measured nature's way. While others debate dry versus moist soil sampling techniques, Haney uses a third method, one that mimics the soil environment of recurrent wetting and drying and relies on nature's extraction tools rather than chemical solvents.
While he has fine-tuned soil analysis for the past 19 years, his test and methodology only became possible with the availability of recent new analytical technology. The extent, time and complexity of the testing are the reason for the higher cost. However, the information gathered is equally more extensive.
The idea of being able to track the impact of practices beyond meeting yield goals or reducing inputs appeals to Archuleta. "I have used other tools, but this gives us a better idea of this elegant universe called soil and how we can predict it will change," he says. "It lets growers track the impact of changes to their management practices. One additional Haney test recommendation is for a suggested ratio of legumes to grasses in cover crops.”
Brandt has already put such recommendations to use. "Before working with Rick, I didn't understand anything about the C:N ratio," he says. "Based on Rick's recommendations, I have added more legumes in some cover-crop mixes and reduced them in others."
As a soil scientist and a farmer (Haney manages the USDA-ARS Temple Experiment Station fields as a farm), Haney appreciates cost savings and environmental benefits. However, he seems equally excited about the test’s ability to measure the impact of cover crops and other management practices on soil fertility. Many, including the NRCS, are advocating combined no-till and cover crops as the solution. While he agrees on the value of both, Haney suggests a slightly different approach.
"What we are seeing is that conventional till systems release nutrients quickly, while no-till soils are slow to release nutrients, taking years to see the benefits," he says. "I would rather see a conventionally tilled field with a cover crop than a no-tilled field without one. We will get the most nutrients possible out of nature by giving soil life the right food with cover crops. Then you can put on the added N, P and K needed, regardless of your system."