No-till soil health begins with less disturbance of it
Soil health is a relatively new buzzword NRCS and its partners are promoting to help educate farmers and landowners on the importance not only of long-term no-till systems but adding cover crops to help increase diversity and structure in the soil that in turn reduces crop inputs.
The first component in this four-part system is managing soils by disturbing them less.
The underlying principle in soil health is to return cropland soils back to their natural state; a lot of plant diversity, low off-site inputs, lime and commercial fertilizers and minimal to no disturbance or tillage.
A good no-till system can do wonders for improving soil in general. The reduced erosion potential, weed competition and increased water infiltration can significantly increase yields over conventional or minimally tilled fields.
On the other hand though, vertical tillage tools marketed as no-till accessories actually reduce water infiltration to that of conventionally tilled fields.
Not only do these implements destroy soil structure, they also oxygenate plant material, which rapidly destroys organic matter built up over the previous year’s no-till planting.
By reducing organic matter, you reduce the water-holding capacity of the soil. Just 1 percent of organic matter can hold about 16,000 gallons of water per acre foot.
Organic matter is also teeming with life — everything from bacteria and fungi to nematodes and larger bugs and earthworms. Everything is feeding on and relying on each other.
As these organisms travel through the soil they create air and water pockets that growing plant roots find before dying and starting the cycle again.
However, if you till a field or drive heavy equipment across a waterlogged area and create compaction, you’re basically generating a tsunami by upheaving all the soil life that takes many years to reform.
When no-till was still new, the common message was be patient. It will take five to seven years for your conventionally tilled yields to return with the transition to no-till. That time frame was given because that’s how long it takes for the soil to repair itself and return to a normal state.
It’s an important message to remember: One pass with a vertical tillage tool or one trip over a field and creating ruts can almost guarantee you years of rebuilding.
The transition to healthy soil begins with eliminating soil disturbance.
Next time we’ll look at the other three aspects to taking soil and crop productivity to the next level.
Andy Gaver is a conservationist with the USDA Natural Resources Conservation Service in Butler County.
