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Archive | Soil Fertility

Book of the Week: Hands-on Agronomy

By Neal Kinsey and Charles Walters

Editor’s Note: This is an excerpt from an Acres U.S.A. original book, Hands-On Agronomy, by Neal Kinsey and Charles Walters. Copyright 2013, 1993. Soft cover, 391 pages. $35.00 regularly priced. SALE PRICE $22.50.

Hands-on Agronomy, by Neal Kinsey and Charles Walters

No one used the term killer agriculture or knowledgeable mining when I was a youngster growing up on a farm in southeast Missouri. We raised corn, wheat, cotton, soybeans and a little hay. We also finished a few cattle. Now, a more mature sense of values brings the reality of our farming operation into focus. Sir Albert Howard identified the horns of the modern farming dilemma: partial and imbalanced fertilization, and toxic rescue chemistry.

Neither I nor my father heard or understood that dictum then, then being the 1950s and 1960s. All we knew was that the crops faltered—not occasionally, but year after year. My father had five sons and he concluded, “I hope you won’t even think about going into agriculture because it costs too much and I am not going to be able to help you get started. I hope you will go into business and be an accountant or something like that.”

Accordingly, I went to college with the intention of becoming an accountant. There was a problem with that. I couldn’t stand being inside four walls all the time. So I changed my direction while I was at the University of Missouri where I met William A. Albrecht, the legendary professor who contributed so much to what Acres U.S.A. calls eco-agriculture. Albrecht gave the Department of Soils its well-deserved reputation, but by the time I arrived, he had been retired—forcibly, I am told—in the wake of a great grant from a fossil fuel company. In any case, his classroom days were over, for which reason I was able to get more of his ear than might have been possible as classroom fare. He taught a private study course for Brookside Laboratory, and I decided to avail myself of this extra-curricular opportunity. He changed my entire way of thinking. Continue Reading →

Soil Sentinels: Harness The Power of Earthworms

When moist, practically all soils from tundra to lowland tropics support the activity of earthworms. Largely unseen, earthworms are a diverse, powerful workforce with the capacity to transform soil into fertile ground.

Found in 27 families, more than 700 genera and greater than 7,000 species, earthworms vary from about 1 inch to 2 yards long. Their living mass outweighs all other animal life forms in global soils. Although we may view earthworms as being both prolific and productive, do we fully appreciate our human capability to favor their beneficial efforts as allies allowing farms and gardens to flourish? I think not.

Earthworms not only play productive roles in sustainable agriculture, but they have enormous capacity to help mitigate our elevated atmospheric greenhouse gas content by reducing carbon and nitrogen gas. Continue Reading →

Cover Crops Don’t Deplete Moisture

Among the myriad of benefits cover crops provide to a row crop or vegetable operation, Clemson University researchers have found another one: Cover crops do not deplete water stored in the soil profile, thus preserving the precious resource for the cash crop — an all important function, specifically in times of drought.

USDA photo showing a cover crop mixture that includes oat, proso millet, canola, sunflower, dry pea, soybean and pasja turnip.

In the Southern Sustainable Agriculture Research & Education (SSARE) On-Farm Research Grant-funded study (OS16-096), “Cover Crop Influence on Stored Water Availability to Subsequent Crops,” researchers evaluated common fall cover crops grown in the state for water use efficiency and biomass production.

“We need to bring biodiversity to our farming systems to alleviate drought stress, and cover crops are one practice that provides the benefits to achieve that,” said Ricardo St. Aime, a Master’s student and Fulbright Scholar from Haiti who worked on the project. “But many farmers are hesitant to adopt cover crops. One reason is that they fear cover crops might bring water resource competition for the following cash crop. We conducted this study to determine whether or not this is true.” Continue Reading →

Book of the Week: Secrets of Fertile Soils

By Erhard Hennig

Editor’s note: This is an excerpt from Acres U.S.A. original book, Secrets of Fertile Soils, written by Erhard Hennig. Copyright 2015, softcover, 198 pages. $24.00 regularly priced. SALE PRICE: $19.20.

Humus forms as a result of the complicated interplay of inorganic conversions and the life processes of the microbes and tiny creatures living in the soil. Earthworms play a particularly important role in this process. Humus formation is carried out in two steps. First, the organic substance and the soil minerals disintegrate. Next, totally new combinations of these breakdown products develop, which leads to the initial stages of humus. Humus formation is a biological process. Only 4–12 inches (10–30 centimeters) of humus-containing soil are available in the upper earth crust. This thin earth layer is all that exists to provide nutrition to all human life. The destiny of mankind depends on these 12 inches!

Secrets of Fertile Soil

Cultivated soils with 2 percent humus content are today considered high-quality farm land. What makes up the remaining 98 percent? Depending on the soil type, soil organisms constitute about 8 percent, the remains of plants and animals about 5 percent, and air and water around 15 percent.

The remaining 70 percent of soil mass is thus of purely mineral origin. The mineral part of the soil results from decomposition and the erosion of rock. The dissolution of these components is carried out by the lithobionts, which can be seen as the mediators between stone and life. It was, once again, Francé who coined the term “lithobiont,” which means “those who live on stone.” The lithobionts are the group of microbes that begin the formation of humus. They produce a life-giving substance from the nonliving mineral. On the basis of this process, living matter, earth, plants, animals, and human beings can begin, step by step, to build.

Only soils with an optimal structural state of tilth have a humus content of 8–10 percent. Untouched soils in primeval forests can, at best, reach 20 percent. A tropical jungle can’t use up all its organic waste, so humus can be stored. All forests accumulate humus, but real humus stores only emerge over the course of millenniums. Once upon a time accumulations of humus known as chernozem (Russian for black earth) could be found in the Ukraine.

Continue Reading →

Book of the Week: The Biological Farmer, 2nd Edition

By Gary Zimmer with Leilani Zimmer-Durand

Editor’s Note: This is an excerpt from Acres U.S.A. original book, The Biological Farmer, written by Gary Zimmer. Copyright 2017, softcover, 518 pages. $30.00 Regularly Priced.

What’s Wrong with the N-P-K Approach to Farming?

Does it make sense to use high levels of only highly concentrated water-soluble nutrients? The N-P-K-pH chemical approach to farming is both incomplete and wasteful.

Nitrogen — Managing nitrogen should not be just mathemati­cal. Crop rotation, the nitrogen source used, and when and where the nitrogen is applied all have a bearing on how much nitrogen we need, as does soil air, soil life, organic matter, and

The Biological Farmer, 2nd Edition

the presence and balance of other elements (such as sulfur and calcium). Biological farmers do not want to use any more nitrogen than absolutely necessary, not only because of cost and possible environ­mental pollution, but also because excess nitrogen suppresses long-term stable biological processes in the soil.

Research from the University of Minnesota has found that corn yields are highest when legumes are added to the rotation (O’Leary, Rehm, and Schmitt, 2008). By including soybeans, alfalfa, or other nitrogen-fixing plants, it is possible to grow your own plant-avail­able nitrogen and reduce fertilizer requirements. Now consider how conventional thinking advocates applying more nitrogen to increase yield. Is yield always increasing as much as the nitrogen applied? Are your added fertilizer dollars getting you results? If not, what happens to the extra nitrogen you apply? Does it benefit the soil, the environment — or your water? What are the overall costs? Continue Reading →

Quest for Quality: Growing Nutrient-Dense Crops

For Central Virginia farmers Dan Gagnon and Susan Hill, the best proof that they’re doing things right with their soil to produce nutrient-dense crops comes from the mouths of babes and customers facing health challenges.

Dan Gagnon discusses soil structure at Broadfork Farm in Chesterfield, Virginia.

Gagnon and his wife, Janet Aardema, operate Broadfork Farm in Chesterfield, Virginia. Gagnon likes to observe how children interact with food. His youngest son Beckett, 3, last winter used organic store-bought carrots to dip into salad dressing while Gagnon’s mom was looking after him. But he would not eat the carrots.

When she dropped him off, Gagnon had just dug some overwintered carrots. Despite a bit of dirt clinging to them, Beckett gobbled them up. “The feedback from customers that we continue to get has been very encouraging,” said Gagnon. “Also, a child’s palate is a great indicator of the quality of your produce.”

Hill, who grew up outside Helena, Montana — where, she says, if they didn’t grow it, they didn’t eat — cooks for a woman who has multiple sclerosis; another customer has cancer and another, Lyme disease. Continue Reading →