“Can you see anything else at this show that gives you 20 per cent more yield while spending less money?”
– COLIN ROSENGREN
When Colin Rosengren was looking for ways to improve the sustainability of farm near Midale, Sask., he turned to the best agronomist he could find – Mother Nature.
It was by clueing into some of the time-tested characteristics of natural cropping systems, zero tillage and diversity, that set him on a path towards a system that he’s finding to be agronomically sound, economically rewarding and logistically manageable.
Rosengren has taken to using the word “husbandry” to describe his farming strategies over “agronomy,” which all too often is used interchangeably with “technology.” While he doesn’t shun technology on his 4,500-acre farm, he’s incorporating techniques that can substantially reduce his reliance on expensive inputs such as pesticides and fertilizer.
Zero tillage, which has been widely adopted on the Canadian Prairies, was a step in the right direction. The next progression will be a move towards intercropping, he predicts.
He started the transition on his farm five years ago, experimenting with peas and canola in the same field. Many predicted one would choke out the other, to the detriment of both. In fact, the opposite occurred; the two crops combined yielded better than if they were grown individually.
What’s more, his input costs are reduced. The competitive nature of the crops chokes out weeds. Some fields require no herbicide applications at all. The field diversity discourages disease, and the legume component reduces his need for fertilizer.
Pests, such as flea beetles, are confused by the mixed canopy and move to other locations. As well, the thick canopy enables straight combining, a further saving of time and money.
Rosengren said over three years the combinations he has tried on his farm have over-yielded conventional monoculture by a range of $6,500 per quarter section to $28,000.
“Can you see anything else at this show that gives you 20 per cent more yield while spending less money?” Rosengren asked a packed seminar at Manitoba Ag Days recently.
As a rule of thumb, he cuts his seeding rate of each crop by a third. He uses a one-pass seeding system modified to seed the various seeds at different depths as well as managing fertilizer placement.
Care must be taken to choose varieties that grow to similar heights and mature at the same time. He separates the crop at harvest using a modified drum roller that sends the seed to separate bins as it is unloaded in the yard. Rosengren said harvest logistics must be planned carefully because that is where the system breaks down for most who attempt it.
“You need to look at things differently in your seed guide,” he said. “You need a variety that is not going to shatter that easily. You have to think further than, ‘what do you spray that with?’”
Rosengren has tried growing three crops at once, canola, barley and peas, and concluded it has potential. He has also tried chickpeas and flax sown in alternating strips, with the flax at a cross angle to the prevailing winds. He believes the
flax acts as a barrier to disease transmission.
And it worked. He required no fungicide applications while neighbours covered their fields four times at a cost of $25 per acre each time.
Combinations of flax and lentils, peas and barley, flax and wheat, camelina and peas, and camelina and red lentils as a relay crop, also show promise, he said.
Rosengren noted that while transitioning into intercropping requires a different approach to management, it is not capital intensive. “One quarter section can buy all the equipment you need to do it, in one year,” he said.