Soil Livestock
Sometime when you’re out in the field this spring, bring a shovel. Dig into the dirt and see how many earthworms, dung beetles, millipedes, and other beneficial subsoil creatures you bring up. If you find a bunch, consider yourself lucky.
Eileen Kladivko is an agronomy professor at Purdue University. She says these organisms are more significant in overall soil health than most people realize.
"Earthworms in particular help build soil porosity, so they can loosen the soil, they can mix the soil, they can build channels that will aid in water infiltration to get water into the soil, make channels that roots can grow in," says Kladivko. "Some of the other organisms, like dung beetles, help incorporate organic material into the soil."
There are two main types of worms. Shallow-dwellers, known as redworms, fishworms, and other names, live in the top 12" of soil and randomly burrow throughout the topsoil. The much-larger nightcrawlers build vertical burrows that can extend down five-to-six-feet or more.
Kladivko recommends checking for the presence of earthworms in the spring or late fall when they’re the most active.
"If you’re just wanting to get some idea out in your field, you can take a shovel, and if every shovel full you have you turn over 3-4 worms then you’re probably doing pretty good," she says. "If it takes you ten shovels before you get a worm, then you’re probably not doing very well."
Encourage earthworm populations by leaving a surface mulch of organic matter and as little tillage as possible.