Both organic and conventional beef and forage producers look for ways to build soil health without breaking the bank. Research and on-farm experience suggest growing perennial legumes and looking at the farm as a system can help producers achieve both goals.
Alan McKenzie runs about 150 cows and 300 calves on a 3,500-acre mixed farm, near Nesbitt, Manitoba. McKenzie and his family switched to organic production in 2002. He says they were already halfway to organic, and they found they could grow a good hay crop without fertilizers and chemicals. Organic premiums were good at the time, too.
“It pencilled out very well,” says McKenzie. “And I never was a fan of spraying or anything like that. I never really liked it that much. So it was kind of an easy fit.”
McKenzie’s rotation includes three or four years of alfalfa. Perennial forages such as alfalfa keep the land clean. After the alfalfa, McKenzie will usually grow flax. Intercropped peas and oats, winter wheat, and soybeans have also found their way into his rotations.
McKenzie also grows a green manure one year out of the rotation. Rather than doing a straight plow-down, he grazes yearlings on the legume.
“You’re still getting some value out of the forage stand in the same year instead of just having a year where it’s all expenses,” he says.
Since going organic, McKenzie says the soil quality is improving steadily — this is partly due to management practices like cover crops and grazing green manure, and using legume crops such as alfalfa and peas to build nitrogen.
McKenzie’s management practices apply to conventional livestock and forage production, too. Since 2008 he has been part of a holistic management club, which was set up with the help of ranchers and holistic management specialists Don and Bev Campbell of Meadow Lake, Sask. The Campbells helped McKenzie develop mob- and rotational-grazing systems.
The holistic management applies to non-organic operations, too, say the Campbells. In fact, McKenzie is the only organic producer in the club. Other members include mixed farmers and beef producers.
MANAGING NUTRIENTS KEY
Since switching to organic production, McKenzie says his biggest battle has been to keep soil nutrient levels up.
“If you can maintain soil fertility and produce 80 per cent of what your conventional neighbour’s crops are yielding, then all of a sudden the organic premiums don’t have to be as big,” he says. “But if you have to take every second year off to rest the land and summerfallow, then I think you’re losing ground.”
McKenzie is bale grazing on pasture as well as grazing green manure and using cattle to add nutrients back to the land. He’s also thinking about sourcing organic manure to apply and boost phosphorus levels.
Researcher Martin Entz, who studies natural-systems agriculture at the University of Manitoba, looked at conventional and organic rotations over 12 years at the university’s Glenlea Research Station. Two rotations included two years of alfalfa, two included a year of peas, and two included clover.
The alfalfa rotations had the highest nitrogen levels, regardless of whether they were organic. But the organic alfalfa rotation had the lowest plant-available phosphorus levels of all six rotations.
Part of the problem is that soil tests only measure inorganic phosphorus. Organic phosphorus, which soil tests don’t pick up, becomes available to plants over time.
But producers also need to make sure they’re not mining the soil, says Entz. Researchers removed hay from one organic plot without adding nutrients, and the system collapsed due to lack of phosphorus. Entz says they’re now adding composted manure to build phosphorus, although ideally he’d like to have livestock grazing the site.
“We need to be sensible about the nutrient cycle in these systems,” says Entz.
He says producers can take samples from the crop about three weeks before harvest, dry it, and send it for a feed test. The feed test will tell farmers how much phosphorus has been removed from the soil and alert producers to shortages in the crop.
Ranchers can use animals to transfer nutrients to deficient areas, which also saves energy. Placing bales in areas where soil nutrients are particularly low will concentrate cattle and manure in that area. Livestock producers in West Africa, for example, corral animals overnight in poor areas to build phosphorus, and Entz is now studying use of a similar practice in Manitoba.
ROTATIONS WITH ALFALFA USE LESS ENERGY
Entz also compared the energy inputs for organic and conventional systems, as well as forage and non-forage rotations. Energy consumption was measured in megajoules per hectare. The study, located at Glenlea Research Farm about 20 kilometres south of Winnipeg, has been running since 1992.
Entz and his colleagues found that including a perennial legume (in this case two years of alfalfa) in a conventional crop rotation lowered the energy inputs substantially, mainly because nitrogen inputs dropped.
Researchers then decided to compare organic and conventional cropping systems. Rotations included wheat-pea-wheat-flax and wheat-alfalfa-alfalfa-flax.
“We got a large boost in energy efficiency from going to the perennial legume, but we got a larger boost going to the perennial legume in the organic rotation,” says Entz.
In terms of energy costs, herbicides are quite cheap, says Entz. But nitrogen fertilizer accounts for half the energy budget. “You can till the field 30 times and that’s about how much energy it takes to make up for the nitrogen application,” he says. The first and third rotation in the accompanying chart shows about much energy is associated with nitrogen fertilizer application.
Since 2003 researchers have been running a small organic “farmette” at the Carman Research Station to further study ways to reduce energy consumption. The farmette has a six-year rotation that includes an annual green manure crop which is grazed by sheep every three years.
Researchers are also minimizing tillage by using a blade roller. The farmette now uses 65 per cent less energy than a neighbouring conventional system and Entz says they’re now shooting for an 85 per cent energy reduction.
Entz and his colleagues have also been looking at the economics of organic and conventional systems at Carman over seven years. A 20 per cent drop in inputs makes the organic system economically comparable to the conventional.
EASIER FOR HOLISTIC OPERATIONS
The Carman research station holds an ecological field day in July, and Entz encourages producers to visit and share ideas. For livestock producers thinking about going organic, Entz suggests they start slowly and ensure grazing systems are in good shape. Practices such as bale grazing and rotational grazing work well in organic systems.
But not all practices may have a fit in an organic system, he says. For example, January calving would be difficult because calves are more likely to need medical intervention for diseases such as scours. “Think about your farm as a system,” says Entz.
“So if you’re already in that place where your ranch or farm is running as a sustainable operation and you as the operator are holistic-minded, it wouldn’t take much to make it an organic operation,” says McKenzie. “It’s more of the paperwork side.”
McKenzie says the best approach is to talk to other organic producers in their area, as they’re generally willing to help. Organic certifiers can also point producers in the right direction.
McKenzie also suggests taking in soil-health workshops. He follows Gabe Brown, a North Dakota farmer who has spoken to producer groups in Western Canada about how he uses cover crops and mob grazing to cut his fertilizer and herbicide inputs, while building soil health.
“A lot of this information is applicable to organic, low-input sustainable farming and conventional farming,” says McKenzie. †