A60-bushel-per-acre crop of wheat would make any farmer proud, but how about one that was grown without pesticides or non-organic fertilizer?
That’s how organic wheat yielded last year on a 1.5-acre field plot at the University of Manitoba’s Ian N. Morrison Research Farm at Carman.
The average wheat yield in the R. M. of Dufferin, where the research farm is located, was 54.3 bushels an acre, according to crop insurance data.
It’s not a fluke, says Martin Entz, a cropping systems and agronomy professor who oversees the university’s organic research trials. It’s evidence that organic agriculture is about much more than idealistic world views and hippie-dippy philosophy.
“The long and the short of it is farmers are applying science to organic farming,” he says.
Organic farmers are matching the yields produced by chemical-based farmers, especially three to five years after they’ve converted, according to a paper written by E. Ann Clark, an associate professor of plant agriculture at the University of Guelph.
“Clearly, organic management is able to provide on-farm N (nitrogen) and pest control comparable to what is purchased off-farm in conventional systems,” Clark writes.
Organic wheat grown at Carman averaged 48 bushels an acre the last five years, compared to the municipal average of 50 and the 10-year provincial average of 41.
Entz’s organic flax did even better, yielding 33 bushels an acre in 2009 compared to the municipal average of 25.
“Because we’ve had a mixture of farmer innovation, which has been absolutely critical, and more scientific investigation, there is no question in my mind organic agriculture is definitely here to stay,” says Entz. “It is very productive and a lot of fun.”
Just as conventional agriculture has benefited from research and improved agronomy, so too has organic production.
“It has been a surprise to many of us, including me, how productive this (organic) system can be and we’re not done yet,” Entz says.
There are tradeoffs. Organic rotations don’t produce a cash crop every year on every field; farmers opt instead to grow green manure crops worked down to restore soil fertility and tilth.
But that hasn’t stopped an organic rotation of spring wheat, soybeans, flax, oats and two green manure crops from outperforming a conventional rotation of soybeans, wheat, canola and oats to the tune of $142 per acre to $81 per acre over a six-year period.
The calculation excludes fixed costs and is based on the organic farmers receiving premium prices while having lower input costs.
But even if crop prices were similar, the organic farmer would be averaging as well as a conventional neighbour because of the lower input costs.
WEED CONTROL IMPROVED
A big step forward in the organics is improved weed control.
“I think we have learned to be comfortable… and not be afraid of the weeds because they can be managed,” he says.
“The weeds haven’t gone away, but I believe with the right rotation and strategic tillage and the use of mulches we can control them.”
The key to managing weeds, as well as other pests in organic agriculture, is diversification, says John Hollinger, organic business development specialist with Manitoba Agriculture, Food and Rural Initiatives. That means rotating crops, including annuals and perennials, grasses and broadleaves and sometimes seeding early and sometimes late.
“You’re always trying to fool the weeds,” he says. “It takes a lot of planning and a lot of forethought because once you have the pest it’s too late.”
Entz has had good success suppressing weeds and conserving moisture with mulches either made from a crop that has been harvested or with late-seeded cover crops or full-season green manure crops.
“We’re not tilling any more than a conventional farmer would,” Entz says. “In fact we might be tilling a little bit less.”
The air seeder, which has increased the efficiency of conventional and zero-till farmers, is a big help to organic producers too, providing them with precise seed placement with reduced or no tillage.
There’s also less need to rely on summerfallow because of improved crop rotations.
“It was our glyphosate; it’s what got us out of a problem year,” he says.
Some tillage is still important, especially periodically late in fall to control Canada Thistle. Crop rotation is key as well. Growing biannual crops like sweet clover as a green manure too often can result in an explosion of Canada Thistle, Entz warns.
The focus now in the organic world is on soil fertility. It’s critical for optimizing yields, but Clark says research has shown nutrient-balanced soils produce crops that are less likely to attract insect and disease pest.
“On rich soils (in Manitoba) you’ve got about 20 years before you’re going to run into any serious problems if you’re just growing grains,” Entz says.
Nitrogen is readily supplied by growing green manure crops and legumes. But over time, as annual crops are produced and harvested, phosphorus and sulphur levels in the soil will decline and need to be restored.
Applying elemental sulphur, which is approved in organic systems, restores the sulphur required.
Phosphorus is more difficult. The best source is through composted manure.
Organic hay producers who are not returning manure to their land will run short of phosphorus faster than annual crop producers.
“The rule of thumb is you remove 15 pounds of phosphorus for every one tonne of hay,” Entz says. “You just do the math. Farmers are removing 80 pounds of phosphorus a year from their hayfields.”
Maintaining soil fertility is a major concern in organic production, says Entz, but could be fixed by recycling nutrients from composted human waste.
“We’re making a big mistake for not allowing those (nutrients) into the organic system,” he says.
To do so would require that human waste be collected separately from industrial waste and then composted properly to destroy any pathogens. [email protected]
“Ithinkwehavelearnedto becomfortable…andnotbe afraidoftheweedsbecause theycanbemanaged.”
– MARTIN ENTZ
7566 5164 5489
Table 1. Yields of green manure and grain crops in the Organic Crops Field Laboratory, Carman, Man. Each parcel of land, or rotation block, can be followed through the table by following a specific colour. Where two crops are listed for a particular year, those crops were grown on two different parts of that rotation block.
2004*200520062007 2008 2009Average
*In 2004, a pea/oat green manure was grown on all six rotation blocks.
3411Year 2 Cereal
Year 3 Pulse
Berseem clover/ alfalfa
Barley or oat/hairy
Year 5 Oilseed