Q: How many earthworms do you need in no-tilled fields?

A: To gain the benefits of a good earthworm population with no-till, you need 8 to 10 worms per square foot of soil 6 to 8 inches deep.

Q: How do you determine how many earthworms you have?

A: Just count them. Take out your shovel when the soil is relatively moist, preferably in the spring or late fall.

Earthworms go deep when the soil gets hot and dry, so dig samples at half a dozen test sites per field, 6 to 8 inches down in the soil and 12 inches square. Break the soil apart and see how many worms you can find in each sample. The magic number is 8 to 10 worms per square foot.

Q: How do you get more earthworms to inhabit your no-tilled soils?

A: Encourage more earthworms by planting cover crops, adding manure and compost, reducing the amount of tillage and disturbance of the soil and by keeping the soil covered with a layer of mulch such as shreddings. Worms like warm (not hot) and moist (not saturated) conditions.

Q: What are the ideal living conditions for an earthworm?

A: Earthworms require an environment with lots of crop residue and a calcium-rich soil. They like shaded conditions such as a cover crop will provide. They tolerate a range of temperatures from freezing to 100 degrees F. They live in almost all soil types, except very coarse soils (sands) and those soils that are…