Interest in intercropping increasing – Organic Matters

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Organic producers are finding benefits to intercropping – seeding two or more crops together in a field.

Field days across the Prairies this summer indicated that interest is growing in this type of diversification.

Intercrops can be plowed down into the soil, with different crops feeding the soil in different ways. Legumes provide nitrogen and cereals provide organic matter, for instance.

Intercrops can also be used as greenfeed – a mixture of peas and oats provides a nutritious mix.

Intercrops can also be used as seed crops if they are well matched. To be harvested together, the crops must be similar in their days to maturity, ease of threshing and required combine sieve sizes and rotor speeds.

Paul Gaucher, an organic producer near Coderre, Sask., led a group through his intercrop fields this summer. Gaucher finds that intercrops allow him more flexibility. With more than one crop at a time, he can “let Mother Nature decide which plants will do best under the conditions of the crop year.”

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A field pea and oats mixture works well on Gaucher’s land in the brown soil zone. Field peas do better in some years, oats do better in other years. Together, each gets some advantage. The oats grow faster than the peas and reduce weed competition. The oats keep the peas up and provide stubble to catch the mixed crop when swathed. Neither crop is preferred by grasshoppers.

Steve Snider of New Norway, Alta., is an organic producer who was named Outstanding Young Farmer in Alberta. He finds intercropping expands his options, responds better to variable conditions, and decreases problems with disease, insects and lodging. Snider mixes field peas with oats or barley. The cereals hold the peas up, and act as a buffer during combining, keeping pea seeds from cracking. The mixture is less weedy than peas alone and cereals in the mixture are less prone to disease.

Elmer Laird from the Back to the Farm Research Foundation, a certified organic research foundation near Davidson, Sask., demonstrated several intercrops this year. Laird advocates intercrops for weed control, insect control and soil improvement.

Yellow mustard and AC Metcalfe barley was a successful mixture this year. Both crops grew vigorously. There were few weeds or insects. Laird said the barley discourages flea beetles and Bertha armyworms.

The research foundation also demonstrated flax intercropped with a variety of other crops, including peas, lentils, beans, wheat, barley and oats. All were seeded on alfalfa stubble. In general, legumes in flax intercrops did poorly this year.

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Cereal-flax intercrops were more interesting. The field with the intercrops had a good catch of lamb’s-quarters. Laird claimed that seeding a cereal with the flax helps to “use up the surplus nitrogen that would otherwise grow weeds.” All cereal-flax intercrops were less weedy than flax alone. Flax did poorly in the oat-flax mixture, though lamb’s-quarters numbers were down. Barley and flax worked well together, with both crops doing well, and weed numbers reduced. Laird reserved judgment on which intercrops worked best until combining was complete.

Organic farmers are experimenting with options that allow them to mimic nature while reducing the negative impact of their weeds. Intercropping may be an option that does just that.

Native prairie is a dynamic mixture of many species. Differences among species, interacting with small-scale differences in the local environment, produce the shifting equilibrium that characterizes these grasslands. In contrast, much of our prairie agriculture strives for single species domination over hundreds of acres. Perhaps we can benefit from incorporating some of nature’s diversity into our cropping systems.

Frick is the Prairie co-ordinator for the Organic Agriculture Centre of Canada located at the University of Saskatchewan. Frick can be reached at 306-966-4975, at brenda.frick@usask.ca, or www.organicagcentre.ca.Opinions expressed in this column are not necessarily those of The Western Producer.

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