Its burrows improve aeration of the soil and make it easier for water to pass through the earth. Its castings readily combine with organic debris to form humus and make the soil more fertile. When earthworm castings are compared to the top six-inch layer of soil (such as your topsoil), we find that they are: Five times as rich in nitrate nitrogen, twice as rich in exchangeable calcium, two and one-half times as rich in exchangeable magnesium, seven times as rich in available phosphorus, and 11 times as rich in exchangeable potassium.
Experiments with earthworms have shown that their presence definitely increases crop production. Daily an earthworm passes the equivalent of its own weight through its digestive tube. When we consider that many thousands of earthworms are doing this in just one acre of cultivated soil, a tremendous job of soil building is being accomplished.
Experiments with earthworms have shown that their presence definitely increases crop production. Daily an earthworm passes the equivalent of its own weight through its digestive tube. When we consider that many thousands of earthworms are doing this in just one acre of cultivated soil, a tremendous job of soil building is being accomplished.