Living Soil Soil is Alive
By John Parker When planting a garden, gardeners may realize that the soil they put those tiny seeds or plants into is "alive" and full…
By John Parker
When planting a garden, gardeners may realize that the soil they put those tiny seeds or plants into is “alive” and full of soil dwelling “creatures.” These creatures are important and gardeners like many of them that are active. Everyone is familiar with some of these valuable creatures, such as earthworms and night crawlers. However, humans cannot see most of them and many live beneath the surface of the soil.
Most important of these creatures or microorganisms are fungi, bacteria and actinomycetes. They are all-important for soil health and help plants and seeds grow and produce food for the dinner table.
Some estimates have been made about how many of these creatures live beneath the surface of the soil. One estimate says there are 1,800 pounds of earthworms, 16,000 pounds of fungi, 9,000 pounds of bacteria and 5,000 to 5,500 pounds of actinomycetes in just the top six inches of an acre of soil. This is an estimate and no one knows for sure how many there are. Numbers can also change depending on the amount of organic matter in the soil.
Organic matter is important for the health of soil, whether it is a 50-by-100-foot garden or 100 acres of corn or soybeans. Crop residue means carbon, which is the food source for these organisms. Carbon is increased by increasing organic matter.
Some soils in the local area have much organic matter in them naturally. One can tell this by how easy it is to till or work up that soil in a garden. Other soils have much less organic matter and are “heavy” clay soils that are more difficult to get ready to plant and usually less productive.
As they work together, soil organisms have a kind of a cycle. First come the earthworms and night crawlers that bring residue to the soil. Then, the fungi, bacteria and actinomycetes join in breaking down carbon and releasing plant nutrients for the garden or field crops. More of these microbes can mean less fertilizer is needed for good crops.
Local farmers do much soil testing to know the organic matter and other nutrients in their soils. They don’t want to use any more fertilizer than necessary because it is expensive and excess can run off fields, causing problems in ponds and lakes.
Many farmers practice “precision farming.” Using GPS systems and soil testing, they put just the right amount of fertilizer in the right places in a field and at the right time. Their planters also place the seed and fertilizer in precise locations to each other in the ground. This can be careful, exacting work on the part of farmers, but they want to avoid run-off and have productive crops.
Gardeners can do some things to improve the organic matter in their soils. When the vegetables are all harvested in the fall, plant a cover crop such as annual rye grass or winter wheat. Then, turn it under the top few inches of soil next spring. Gardeners may receive manure from their farmer friends to help in their gardens, but they will usually get more weed seeds in the manure.
Farmers leave much residue, such as corn stalks, on their fields. Others are planting more winter cover crops that they work in the soil come spring.
Lets hope the frosts back before Memorial Day did not damage too many plants. Remember that as people work in their gardens, they are working with soil that is “alive.”
Parker is retired from Ohio State University and an independent agricultural writer.
