Disturbing the soil as little as possible helps maintain soil health. This can be accomplished by growing as many different species of plants in the soil as often as possible to keep the soil armored with residue. There are many sources of food in the soil that feed the soil food web, but there is no better food than the sugars exuded by living roots. When using limited crop rotations, a mix of cover crops can fill the gap to improve crop diversity.
In August, NRCS Idaho and partners held three workshops throughout southern Idaho to help producers learn about managing their soil health. Improving soil health starts by understanding aggregate stability. Soil aggregates are groups of soil particles that bind to each other more strongly than to adjacent particles. Glomalin and polysaccharide exudates acts like a glue to cement the micoaggregates together to improve soil structure. An agricultural system that combines a continuous living cover (cover crops) with continuous long-term no-till is a system that closely mimics a natural system and should restore soil structure and soil productivity. When we till our soils, the soil aggregate is broken down and excessive oxygen gets into the soil allowing bacteria to flourish and rapidly decompose the active carbon needed to stabilize macroaggregates. When a soil is left naked, hungry, thirsty and running a fever the soil cannot function as intended and we will see the symptoms (crusting, surface sealing, compaction, poor water infiltration, wind and water erosion) of poor soil health.
To find out more about soil aggregates and how to improve soil health, the following link contains the Power Point presentations from the presenters: Ray Archuleta, Dr. Rick Haney and Marlon Winger. There are also several publications on soil health and cover crops on the site. http://www.id.nrcs.usda.gov/technical/agronomy.html
By Marlon Winger, NRCS State Agronomist
Source: Ag Weekly