By Stephanie McLain

Every year farmers wait to see what kind of spring occurs. The optimist in people hopes for a “good spring.” A good spring would include warming temperatures, minimal moisture and nice winds that allow soils to dry so farmers can get in the field in a timely manner. 

Recent springs with cold, wet conditions have taken this “dream spring” and thrown it out the window. Instead of hoping for a good spring, farmers just hope they can get in the field before the end of May. 

This year, Indiana’s spring brought excessive rainfall and prolonged ponding or flooding in many regions. These early-season rainfall events can have a significant impact on soil health. Driving rain on bare soil causes soil particles to explode off the surface and land up to 6 feet away. Loose soil particles fall into cracks and crevices on the surface and plug these natural infiltration points, causing surface sealing. 

Water can no longer infiltrate this sealed soil. Instead, water quickly flows to the lowest point, causing ponding, or runs off to the nearest water channel and contributes to flooding. Surface sealing, flooding, ponding and erosion can remove valuable topsoil, nutrients, organic matter and soil organisms.

Restore soils
If your farm was affected by early-spring ponding and flooding, consider using cover crops to rebuild lost production capacity and improve soil health. Extended ponding or flooding can kill beneficial soil biology by suffocating them. Soil biology breathes air, and without it, they die. 

These biologically dead areas need to be rescued by adding living roots and air back into the soil. Don’t use tillage. Stirring of the soil may temporarily aerate it, but that also creates a downward cycle of declining soil health. Loose soil will again move with rainfall and plug up the soil surface, causing ponding and crusting and killing soil biology. 

Growing something green during all times of the year is a key concept for benefiting soil structure, improving soil function, building soil organic matter, protecting the soil, improving water and nutrient cycling, and in turn, increasing soil health. If you have some areas that didn’t get planted this spring, consider a summer cover crop mix of millet, sorghum-sudangrass, sunn hemp, sunflower, buckwheat and other summer annual cover crops. Such a mix will help restore soil biology, improve organic matter, control weeds and prevent erosion.

McLain is the state soil health specialist with the Natural Resources Conservation Service in Indiana. She writes articles about improving soil health on behalf of the Indiana Conservation Partnership.