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Unearthing The Potential

As I looked down at the thick mat of rotting vegetation PhD student Caroline Halde was holding up for me to peruse, it was hard to fathom – at first – why anyone but the most devoted of researchers would find this exciting.

I was at the University of Manitoba’s Ian N. Morrison Research Farm at Carman, which is living up to its namesake when it comes to innovative thinking in production agriculture.

Halde is studying organic, no-till cropping systems, looking for ways in which farmers can pursue organic crop production without having to do so much tillage.

Long thought to be at the opposite sides of the production spectrum, both conventional and organic systems offer benefits to farmers and the environment, but both are flawed. One depends on destructive tillage as the chief means of weed control. The other depends on herbicides, which are facing increased resistance in the weed populations.

Until recently, marrying the two seemed unlikely in the world of E-Harmony, where potential mates are matched according to compatible traits.

But then researchers started exploring the use of cover crops and mulches. Cover crops were initially viewed as a means of producing fertilizer. As it turns out, some of these cover crops, particularly a legume called hairy vetch, are also pretty good at controlling weeds.

Hairy vetch is a viney, crawling plant with pretty purple flowers; it climbs the weeds, pulls them down and smothers them as it competes for sunlight.

The researchers dig up a plant to show me its ripe, red nitrogen-fixing nodules. It produces about the equivalent of alfalfa. All it needs is sun and soil.

Even after it is rolled and crimped to be left as biomass on the soil’s surface, it keeps growing until winter. In the spring, its remnants form the thick mulch into which an annual crop can be seeded directly.

Organic wheat sown into plots that grew hairy vetch the previous season is noticeably free of weeds in these replicated trials – which is no small feat in a weedy heyday like this year. Organic flax sown into hairy vetch mulch in 2009 yielded 33 bushels per acre. In 2010, it yielded 24.

Granted, when land is growing hairy vetch, it isn’t producing an annual crop, unless it is being grazed. Plus, the organic farmer must still control weeds in the other years of the rotation cycle.

This work is in its infancy. There are lots of unanswered questions about equipment, timing and the right rotation cocktail.

But even if there is only one year in a conventional farmer’s rotation with reduced or zero herbicides and no nitrogen costs, this could be an important resistance-management tool, and a money saver too.

Halde’s work is based in part on production methods in Brazil – now one of Canada’s biggest competitors in the export market. She has been invited to speak about her work in Korea later this year.

Ohio State University has recently coined the acronym “ECO Farming” to highlight local efforts to reduce tillage through the use of cover crops.

“ECO Farming stands for ‘Eternal no till, Continuous living cover, and Other best management practices,’” says Jim Hoorman, assistant professor and OSU Extension cover crops specialist.

Hoorman, along with Ray Archuleta of the Natural Resources Conservation Service, Ohio No-till Council president Dave Brandt and Ohio NRCS agronomist Mark Scarpiti collaboratively defined the ECO Farming concept.

“Continuous living cover means farmers try to keep a living crop on the soil 100 per cent of the time,” Archuleta said in a release. “The goal is to protect the soil from soil erosion, increase water infiltration, and decrease nutrient run-off.”

Examples include grain crops followed by cover crops, pasture or hay systems, or perennial plants.

Brandt has been practising the concept on his farm for 15 years and said he has reduced his fertilizer inputs by 50 to 70 per cent and herbicide costs by 50 per cent. He also has reduced his fuel consumption. In the process, he has added soil organic matter, which has improved soil health and increased crop yields.

“For 100 to 200 years, farmers have been tilling the soil and basically mining it of nutrients, destroying soil structure and losing 60 to 80 per cent of soil organic matter,” Archuleta said. “Now we can use advanced knowledge of soils, soil health and soil ecology to work with Mother Nature rather than against her.”

No one is promoting hairy vetch as a panacea, and it is unlikely to replace conventional systems any time soon. But think about it. Out of all the tours, all the new technology you’ve been exposed to recently, how many new products out there offer improved weed control and free fertilizer?

You would think, given their production costs, farmers here would be all over this. Yet they seem remarkably disinterested.

These budding scientists are energized by their preliminary findings, and rightfully so. Some day, the rest of us might be too. [email protected]

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