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Calculating the Value of Organic

Root nodules on hairy vetch.

Root nodules on hairy vetch store nitrogen captured from the air with help from Rhizobium bacteria. The stored nitrogen is released into the soil when the plant dies.

A team of international scientists has shown that assigning a dollar value to the benefits nature provides agriculture improves the bottom line for farmers while protecting the environment. The study confirms that organic farming systems do a better job of capitalizing on nature’s services.

Scientists from Australia, Denmark, New Zealand, the United Kingdom and the United States describe the research they conducted on organic and conventional farms to arrive at dollar values for natural processes that aid farming and can substitute for costly fossil fuel-based inputs. The study appears in the journal PeerJ.

“By accounting for ecosystem services in agricultural systems and getting people to support the products from these systems around the world, we move stewardship of lands in a more sustainable direction, protecting future generations,” said Washington State University soil scientist John Reganold. Continue Reading →

Biochar: Helping Everything from Soil Fertility to Odor Reduction

Biochar is seen as a valuable soil amendment and much attention has been placed on using biochar to boost soil fertility and microbiology, upgrade soil structure and accelerate plant growth. Amid a rising tide of research and trials, what was once mostly fuel or water filtration media suddenly sprouted dozens of innovative applications and benefits.

Biochar in Poultry Farming

Farmer Josh Frye with his gasifier.

New biochar uses are being discovered, including:

  • Stormwater management and treatment;
  • Phosphorus traps to reduce water pollution;
  • Nitrogen traps to reduce ammonia and nitrate pollution;
  • Reclamation of mine tailings;
  • Building material blended with cement, mortar, plaster, etc.;
  • Electronic microwave shielding;
  • Electron storage and release as a “super-capacitor”;
  • Carbon fiber textiles for odor-absorbent clothing; and
  • Carbon nanofibers to replace plastic and metal.

Livestock farming is offering a new and growing area of unexpected uses for biochar. Animals from earthworms to chickens, cattle and even monkeys, show shrewd interest in biochar added to their food. Farmers and scientists around the globe have investigated the use of biochar in livestock production. In the European Union, biochar is carefully defined and approved for use in agriculture. Currently, most is fed to livestock and then spread on land with manure.

This article mainly addresses poultry production, but similar issues and opportunities face other livestock producers. Research from several countries shows that adding 1 to 3 percent biochar to cattle feed improves feed efficiency by 28 percent, reduces methane by 25 percent and increases rate of weight gain by 20 percent. Continue Reading →

Soil Ecosystems: Maintaining Critical Microbial Life

earthworm soil life.tifSoil ecosystems aren’t always the first things people notice when they are in nature.

When asked to describe a forest or a meadow, most people would probably begin with the plants, the species diversity or the color of the foliage. They probably wouldn’t pay much attention to the soil ecosystems and the critical microbial life. But a new Yale-led study shows the importance of earthworms, beetles and other tiny creatures to the structure of grasslands and the valuable soil ecosystem services they provide.

During a 3-year study, researchers found that removing these small animals from the soil of a replicated Scottish sheep meadow altered the plant species that grew in the ecosystem, reduced overall productivity and produced plants that were less responsive to common agricultural management, such as fertilization.

The results reflect the long-term ecological impacts of land use changes, such as the conversion of forests to agricultural land, researchers say.

“We know these soil animals are important controls on processes which cause nutrients and carbon to cycle in ecosystems, but there was little evidence that human-induced loss of these animals has effects at the level of the whole ecosystem on services such as agricultural yield,” said Mark Bradford, lead author of the study published in the Proceedings of the National Academy of Sciences.

This article appears in the December 2014 issue of Acres U.S.A.

Soil Ecosystems: Nutrient Additions

New research from Iowa State University shows that agricultural inputs such as nitrogen and phosphorus alter soil microbial communities and soil ecosystems. Adding nitrogen and phosphorus fertilizers, commonly used as fertilizers, to the soil shifts the natural communities of fungi, bacteria and microscopic organisms called archaea that live in the soil, said Kirsten Hofmockel, associate professor.

Hofmockel and other scientists associated with the Nutrient Network, a global group of scientists, revealed that microbial community responses to fertilizer inputs were globally consistent and reflected plan responses to the inputs. Many soil microbes perform helpful functions in the native ecosystems and altering those microbial communities may have negative environmental consequences, Hofmockel said. The researchers found nutrient additions favored fast-growing bacteria and decreased the abundance of fungi that share a symbiotic relationships with grassland plants.

This encapsulation of the research is from the December 2015 issue of Acres U.S.A.

Soil Ecosystems: Synthetic Nitrogen Lingers for Decades

Nitrogen fertilizer applied to crops lingers in the soil ecosystems and leaks out as nitrate for decades towards groundwater — “much longer than previously thought,” scientists in France and at the University of Calgary say in a new study.

Thirty years after synthetic nitrogen (N) fertilizer had been applied to crops in 1982, about 15 percent of the fertilizer N still remained in soil organic matter, the scientists found.

After three decades, approximately 10 percent of the fertilizer N had seeped through the soil ecosystem toward the groundwater and will continue to leak in low amounts for at least another 50 years.

The findings show that losses of fertilizer N toward the groundwater occur at low rates but over many decades, says Bernhard Mayer, U of C professor of geochemistry and head of the Applied Geochemistry Group.

That means it could take longer than previously thought to reduce nitrate contamination in groundwater, including in aquifers that supply drinking water in North America and elsewhere, he says.

“There’s a lot of fertilizer nitrogen that has accumulated in agricultural soils over the last few decades which will continue to leak as nitrate towards groundwater,” Mayer says.

Canada and the United States regulate the amount of nitrate allowed in drinking water. In the 1980s, surveys by the U.S. Environmental Protection Agency and the U.S. Geological Survey showed that nitrate contamination had probably impacted more public and domestic water supply wells in the United States than any other contaminant.

The study, “Long-term fate of nitrate fertilizer in agricultural soils,” was published in the Proceedings of the National Academy of Sciences.

This summary appears in the December 2013 issue of Acres U.S.A.

Interview: Poisoning Paradise for Profit — International Organic Authority, Author & Farmer André Leu Shatters the Myths of Safe Pesticides

André Leu Interview

André Leu

André Leu interviewed by: Chris Walters


Over the years a queasy complacency has replaced the alarm once triggered by the subject of pesticides. While millions of people strive to avoid using them or eating food containing residues, many millions more accept their continued use in the belief that agricultural chemicals are understood, regulated and used with discretion. André Leu’s new book, The Myths of Safe Pesticides, demolishes these notions with a steady stream of hard facts derived from solid science. He puts a hand grenade into the layer cake of wishful thinking, and there isn’t much left after it goes off. As he explains, Leu was moved to write the book by repeated exposure to a series of mistaken ideas about pesticides, massaged into the public mind by public relations professionals working for industrial ag concerns. He hears these dangerous misapprehensions parroted far and wide as he travels the world in his capacity as president of IFOAM, the international organic umbrella group. Hailing from Queensland, Australia, Leu raises tropical fruit in a bucolic spot where the tropical rainforest meets the Great Barrier Reef. His activism on behalf of sustainable farming brought him increasing prominence over several decades, leading to his current post. He is a longtime friend of Acres U.S.A.

ACRES U.S.A. Every so often an apologist for mainstream agriculture takes the line that Rachel Carson and her supporters overstated the problem, since their apocalyptic fears of pesticide effects were not borne out in the decades following publication of Silent Spring. DDT was banned, better chemistry came on the market, integrated pest management techniques evolved, and so on. The world didn’t end. What do the facts really tell us?

ANDRÉ LEU. The reality is that after generations of increasing life expectancy, we’re at the point now in the developed world where we are looking at the first generation that will have a shorter life expectancy than ourselves, so we can see that something clearly isn’t right. If you look at the U.S. President’s Cancer Panel report, it clearly says that 80 percent of cancers are caused by what we call outside environmental influences, of which chemicals are one of the most considerable causes. That is also backed up by the International Agency for Research on Cancer which says breast cancer, for instance, is at an epidemic level when we measure the number of women getting it and the number of women dying. In the developed world we have much better medical intervention, so we’re getting higher survival rates. In the rest of the world, where they don’t have our level of medical care, there’s incredible mortality. The United Nations’ World Health Organization maintains an environmental program looking at endocrine disrupters, particularly diseases of the sexual tissues. Those cancers are on the rise — birth defects, lower reproductive rates. Across the board we can see negative health outcomes as a result of chemicals. This is borne out by good, peer-reviewed science. It’s not dogma, it’s published, peer-reviewed science, meta-studies by the WHO and findings of the President’s Cancer Panel in the United States. We’re talking about some of the world’s best experts getting together, reviewing all the data and presenting their findings. They cannot be discredited and ignored. Continue Reading →

More Accurate Soil Testing

soil testingSoil testing that determines needed fertilizer will measure nitrate in the soil, but tests don’t sufficiently account for soil microbes, which mineralize organic nitrogen and make more of it available to a crop. As a result, farmers often apply more fertilizer than necessary.

Richard Haney, a U.S. Department of Agriculture soil scientist in Temple, Texas, has developed soil test that replicates some of the natural processes that occur in a field and accounts for microbial activity, along with measuring nitrate, ammonium (NH4) and organic nitrogen.

The new soil test is known as the Soil Health Tool. It involves drying and rewetting soil to mimic the effects of precipitation. It also uses the same organic acids that plant roots use to acquire nutrients from the soil. The testing tool measures organic carbon and other nutrients, accounts for the effects of using cover crops and no-till practices and works for any crop produced with nitrogen or other types of nutrient fertilizer. For more information visit http://www.ars.usda.gov/is/pr/2014/140710.htm

This article appears in the September 2014 issue of Acres U.S.A.

Companion Planting: The Magic of Corn, Beans and Squash

Companion planting

Companion planting is an important part of any gardener or farmer’s planning.

Recent discoveries in quantum physics, microbiology and ecology verify something gardeners have long known. Everything in nature is related. There are no solid lines between the plants’ roots, the soil and the bacteria and fungi tying it all together. To help understand why garden crops do or do not thrive, we are led into the enigmatic field of companion planting.

Just as we work and feel best around our friends, plants will grow better in their preferred company. Although the reasons may be obscure, a lot of observation and a little intuition can reveal mutual attractions and aversions. The garden teaches us the value of old-time practices, fresh experiments and keeping our eyes open. Continue Reading →