Keep it cloddy to dodge winter wind erosion
Soil conditions that are typically seen as negative during the crop season could help keep things in better shape this winter, especially when high winds make soils susceptible to erosion, which is most common during this time of year, 2 specialists say.
In some areas, tillage is a seen as a necessity. But, when winds are as high as they've been in some spots where they're less common, that previous soil preparation could bite you as hard as those cold winds do when the temperatures dip, according to a recent report from Kansas State University (K-State) Extension soil management specialist DeAnn Presley and USDA-ARS soil scientist John Takarko. In other words, if worked ahead in the fall to prepare a smooth, mellow seedbed, you're going to be more susceptible to wind erosion when the winter winds kick up.
"When vegetation is insufficient, ridges and large soil clods are frequently the only means of controlling erosion on large areas. Roughening the land surface with ridges and clods reduces the wind velocity and traps drifting soils. A cloddy soil surface will absorb more wind energy than a flat, smooth surface. Better yet, a soil surface that is both ridged and cloddy will absorb even more wind energy and be even more effective in reducing the potential for wind erosion," Presley says. "Soil crusts and frozen ground also can increase resistance of the surface soil to wind forces, but this effect is only temporary and should not be relied on for erosion control."
This time of year, clods are a good thing. The larger the "soil aggregates," the better able your soils will be to weather high winds without becoming eroded. And, the value of clods right now depends on your soil type; if you're sitting on a heavy loam soil, for example, you're in better shape.
"If clods are large and stable enough, as smaller particles are removed or trapped, the surface becomes stable or 'armored' against erosive action. The duration of protection depends on the resistance of the clods to abrasion or changes in the wind direction," Presley says. "Of the factors that affect the size and stability of soil aggregates, most notable is soil texture. Sandy or coarse-textured soils lack sufficient amounts of silt and clay to bind particles together to form aggregates. Such soils form a single-grain structure or weakly cemented clods, a condition that is quite susceptible to erosion by wind. Loams, silt loams, and clay loams tend to consolidate and form stable aggregates that are more resistant to erosive winds. Clays and silty clays are subject to fine granulation and more subject to erosion."
Finally, what exactly you've done in terms of tillage and soil preparation -- and under what kind of moisture conditions those actions were taken before winter -- will have a lot to do with the likelihood of wind erosion in your fields during these cold, windy winter days.
"Mechanical action, such as tillage, animal or machine traffic, and abrasion by saltating soil particles also can affect cloddiness. Tillage may either increase or decrease clods at the surface, depending on the soil condition in the tilled layer and the type and speed of the implement. Repeated tillage usually pulverizes and smooths dry soils and increases their erodibility, especially if done with implements that have an intensive mechanical action, such as tandem disks, offset disks, or harrows," Presley says. "Soil water at the time of tillage also has a decided effect on cloddiness. Research has found that different soils have differing water contents at which soil pulverization is most severe. If the soil is extremely dry or extremely moist, smaller clods are produced than at intermediate water contents."