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Healthy Soils for a Healthy Life — Increasing Soil Organic Matter through Organic Agriculture

Better infiltration, retention and delivery to plants helps avoid drought damage. Organic is on the left, conventional on the right. Photo courtesy of Rodale Institute

Better infiltration, retention and delivery to plants helps avoid drought damage. Organic is on the left, conventional on the right. Photo courtesy of Rodale Institute

by André Leu

This year has been declared the International Year of Soils by the 68th UN General Assembly with the theme “Healthy Soils for a Healthy Life.” I am particularly pleased with the theme because this is a message that we in the organic sector have been spreading for more than 70 years, and at first we were ridiculed. Now there is a huge body of science showing that what we observed in our farming systems is indeed correct.

“Organic farming” became the dominant name in English-speaking countries for farming systems that eschew toxic, synthetic pesticides and fertilizers through J.I. Rodale’s global magazine Organic Farming and Gardening, first published in the United States in the 1940s. Rodale promoted this term based on building soil health by the recycling of organic matter through composts, green manures, mulches and cover crops to increase the levels of soil organic matter (SOM) as one of the primary management techniques.

Numerous scientific studies show that SOM provides many benefits for building soil health such as improving the number and biodiversity of beneficial microorganisms that provide nutrients for plants, including fixing nitrogen, as well as controlling soilborne plant diseases. The decomposition of plant and animal residues into SOM can provide all the nutrients needed by plants and negate the need for synthetic chemical fertilizers, especially nitrogen fertilizers that are responsible for numerous environmental problems. Continue Reading →

The Soil Solution

The Soil Solutionby Graeme Sait

The UN has named 2015 International Year of Soils, and we should embrace this initiative with open hearts and willing hands. It is an incredibly timely focus in light of a series of serious challenges impacting our future and perhaps our very existence. Soil health directly affects plant, animal and human health. It also impacts topsoil erosion, water management and ocean pollution. Most importantly, it is now recognized that climate change is directly related to soil mismanagement. I believe a global soil health initiative can help save our planet.

The Top Five Threats

While in the UK, I met with a professor who shared some deeply concerning findings. He informed me that a recent survey of leading British scientists revealed that as many as one in five of the best thinkers in the country believe that we will be extinct as a species by the end of this century, or perhaps much earlier. This information should serve to spur meaningful action from every one of us. There are five core threats that need to be urgently addressed, and they all relate back to the soil. Continue Reading →

Fish Fertilizer Meets Nitrogen Needs

Organic LettuceThe authors of a new study have found that hydrolyzed fish fertilizer holds promise as an economically feasible nitrogen source for growing organic vegetables.

“Soluble organic nitrogen sources suitable for fertigation in organic vegetable production are much needed,” said lead author of the study, Charles Ogles. Ogles and colleagues at Auburn University studied the effects of three different nitrogen sources during a two-year crop sequence of yellow squash and collards. The scientists used hydrolyzed fish fertilizer, inorganic nitrogen (N) source with secondary and micronutrients, inorganic nitrogen without secondary or micronutrients and a zero nitrogen control for the study. Nitrogen was applied at recommended rates for both squash and collards, 80 percent of the recommended rates and 60 percent of the recommended rates. The study design included a zero nitrogen treatment used as the control.

“To eliminate the rotation order effect, the crops were switched each year: yellow squash-collard in year one and collard-yellow squash in year two” said Ogles. Continue Reading →

Humans Have Huge Impact on Soil Loss

Human impact on soil loss.A new University of Vermont study on soil loss reveals that removing native forest and starting intensive agriculture can accelerate erosion so dramatically that in a few decades soil loss is as high as would naturally occur over thousands of years. Along the southern Piedmont from Virginia to Alabama — that stretch of rolling terrain between the Appalachian Mountains and the coastal plain of the Atlantic Ocean — clay soils built up for many millennia. Then, in just a few decades of intensive logging and cotton and tobacco production, as much soil eroded as would have in a pre-human landscape over thousands of years, the scientists note. The study on soil loss was presented in the journal Geology and reported in the March 2015 issue of Acres U.S.A.

Interview: SOS: Save our Soils — Dr. Christine Jones Explains the Life-Giving Link Between Carbon and Healthy Topsoil

Christine Jones Interview

Christine Jones

Dr. Christine Jones, interviewed by Tracy Frisch


To the pressing worldwide challenge of restoring soil carbon and rebuilding topsoil, the Australian soil ecologist Dr. Christine Jones offers an accessible, revolutionary perspective for improving landscape health and farm productivity. For several decades Jones has helped innovative farmers and ranchers implement regenerative agricultural systems that provide remarkable benefits for biodiversity, carbon sequestration, nutrient cycling, water management and productivity. After a highly respected career in public sector research and extension, in 2001 Jones received a Community Fellowship Award from Land and Water Australia for “mobilizing the community to better manage their land, water and vegetation.” Three years later she launched Amazing Carbon as a means to widely share her vision and inspire change. Jones has organized and presented workshops, field days, seminars and conferences throughout Australia, New Zealand, South Africa, Zimbabwe, Europe, the United States and Canada. Last year, she gave presentations to American organizations and institutions as diverse as Arizona State University, NRCS, Pennsylvania No-Till Alliance, the Massachusetts chapter of Northeast Organic Farming Association (NOFA), San Luis Valley Soil Health Group and the Quivira Coalition. In 2015 Jones’ personal commitment to make the biggest possible impact globally will take her to Alberta, Saskatchewan, Manitoba, Ontario, Kansas, New Mexico, California, Florida, Costa Rica and South Africa, as well as many regions within Australia and New Zealand. In early March she travels to Western Australia, 2,500 miles from her home, to hold the first in a series of Soil Restoration Farming Forums, in which 11 farmers will receive monetary awards for reversing soil deterioration in dryland cropping systems through intercropping with perennial warm season grasses.

ACRES U.S.A. You’ve written that the most meaningful indicator for the health of the land and the long-term wealth of a nation is whether soil is being formed or lost. Yet there’s a widespread belief, actually dogma, that the formation of soil is an exceedingly slow process. Even some organic researchers accept that idea. You describe the formation of topsoil as being breathtakingly rapid. Continue Reading →

Biochar Alters Water Flow

Vincent Mina demonstrates biochar production in Maui.As more gardeners and farmers add ground charcoal, or biochar, to soil, a new study by researchers at Rice University and Colorado College could help settle the debate about one of biochar’s biggest benefits — the seemingly contradictory ability to make clay soils drain faster and sandy soils drain slower. The study, published in PLOS ONE, offers the first detailed explanation for the hydrological mystery.

“Biochar is light and highly porous,” said lead author Rebecca Barnes. “When biochar is added to clay, it makes the soil less dense and it increases hydraulic conductivity, which makes intuitive sense. Adding biochar to sand also makes it less dense, so one would expect that soil to drain more quickly as well; but in fact, researchers have found that biochar-amended sand holds water longer. … By adding our results to the growing body of literature, we show that when biochar is added to sand or other coarse-grained soils, there is a simultaneous decrease in bulk density and hydraulic conductivity, as opposed to the expected result of decreased bulk density correlated with increased hydraulic conductivity that has been observed for other soil types.” The study was summarized in the January 2015 issue of Acres U.S.A.