Why Soil Health is so Important for Your Crops
October 1, 2021 By Lane Carlson, grade 8 (Slightly Edited by Jerry Carlson)
We have yet to fully understand how God designed the many interactions between a crop, biological activity, chemistry and still unknown relationships at work within the soil.
We do know that a plant’s functions rely on a steady exchange of minerals, sugars and complex enzymes between the soil’s fungi, beneficial bacteria and the plant. Dr. Rick Haney, a soil scientist with USDA’s Ag Research Service based in Temple, Texas, developed an effective way to estimate the biological activity in soil which is essential for plant growth. It’s known as the Haney soil health test, and measures carbon dioxide released by soil organisms.
In a Yale Environment 360 news article, Haney said: “We are only at the tip of the iceberg in terms of what we understand about how soil biology functions. We are at the beginning, and anyone who tells you that they know what is going on in soil is either lying or trying to sell you something. It’s mind-bogglingly complex to understand all the interactions, because it’s a dynamic, living system.”
From what we know regarding these interactions, 40% to 50% of the sugar that a plant leaf makes flows through the plant’s vascular system into roots. The roots exude these nutrients to feed beneficial bacteria and fungi in the soil. Fungi dissolves most of the big chunks of raw organic matter such as crop residue. When fungal microbes die, their remains are full of broken-down minerals which beneficial bacteria break down even more. These nutrients become soluble, so crop roots can “drink” these minerals and use them to grow.
The reason cover crops are so useful to cover bare ground is because each species of cover crop attracts around ten different types of bacteria and fungi. So when it’s time to plant the actual crop, the soil is full of bacteria and fungi to give the crop more nutrients and minerals it needs. As a plus, when the cover crops die down, they give the fungi and organisms fresh organic matter to break down, to later feed the crops once again.
All soil microbes require oxygen and warmth to stay alive. They act almost like people. There can also be billions of these little guys living in a gram of soil around the plant’s roots, but only a fraction of that density survives in soil without roots to feed them.
These are what keeps everything in a steady loop and what keeps the plants healthy. Soil organisms absorb oxygen to create energy. They breathe out carbon dioxide as a waste product. As this carbon dioxide rises from the soil, it feeds leaves in the plant canopy. Years ago, researchers at USDA’s National Laboratory for Agriculture and the Enviornment confirmed that about 40% of total plant matter in a crop like soybeans or corn is built from carbon dioxide exhaled from soil microbes.
There are also a few Bible verses that illustrate how complex the soil really is. An example:
Mark 4:27–28 “Night and day he sleeps and wakes, and the seed sprouts and grows, though he knows not how. All by itself the earth produces a crop: first the stalk, then the head, then grain that ripens within.”