Your Reading List

Midwife Crop Could Help Green Shoots Break Through

Aunique trial at the Brandon AAFC research farm will see if planting seed of other crops in the furrow along with canola can help the notoriously weak seedlings break through the soil crust and improve establishment rates.

Research scientist Byron Irvine said that companion crops such as canary seed, flax, camelina, and golden German millet with the Roundup Ready, LibertyLink and Clearfield canola could help the cotelydons physically break through and get off to a better start.

“It’s a bit speculative. What we’re hoping to do is essentially provide additional force to get the canola through the ground,” he said.

“We’re planting them in the same row and at a fairly high rate because we know that we’re going to spray everything anyway to kill them out very early.”

With hybrid canola seed worth about $8 per pound, he added, any successful strategy for getting more seedlings emerging from the tiny seeds to break through the surface would help farmers reduce costs and improve yields.

CUTTING COSTS

“If you have 90 per cent germination which is a Canada No. 1 you’re lucky to get half of the seeds making it to the surface,” he said.

Irvine noted that even when using the research farm’s small, specialized, highly precise seeders at one mile per hour on a perfectly prepared seed bed, seedling emergence rarely exceeds 60 per cent of all viable seeds.

That’s because no matter how hard you try to get it right, some seed depth variation always shows up.

Under real-world conditions, he added, when a farmer is trying to get all his acres sown, there is a well-known trade-off between seeding speed and accuracy.

In the trial, possibly the first of its kind, relatively low-cost crops with seed sizes similar to canola were chosen.

“We don’t know if this works or not, but with big seeds, you’d have trouble keeping them all in a mixture,” he said. “If you dumped them into the seed tank

FILE PHOTO

HELPING HAND: Researchers with AAFC in Brandon think using midwife crops could help improve canola seedling emergence.

together, all the small seed would settle out the bottom.”

Other options being considered include putting a mustard variety in with the canola to give flea beetles an alternative food source to divert their attention away from the main crop, but that was not included in the study this spring, which aims to look at the physical soil-moving aspect alone.

About 80 plots at the Brandon research farm will test the results at shallow-, medium-and deep-seeding levels, he added.

Other “quirky” studies being undertaken include an ongoing trial of “in-crop” fallow under an organic protocol.

QUIRKY STUDIES

Similar to row cropping, a rotation of flax or wheat is planted at double rates in two-foot-wide strips with alternating strips of equal size between. Instead of using tillage to control weeds in the fallow strips, a mower is used to prevent seed set.

“You’re only seeding half the available area without increasing the total amount of seed,” said Irvine, adding that the rate amounts to 240 pounds per acre in the seeded strip, up from the normal rate of 120 pounds per acre. That means seeding rates are effectively doubled, but without increasing the seeding costs.

“You might think that we’re wasting light and water, but when you’re going organic the big thing is to manage weeds, which can chew up light and water.”

Such a strategy could work for a farmer using the RTK guidance system and a modified disc mower, he added, but the researchers are just using a lawn mower to cut between the rows for the purposes of the study that is currently aiming at “proof of concept.”

REDUCING EROSION RISK

The next year of the rotation, the crop is put into the fallow rows. By not using tillage, the soil stays covered and erosion risk is prevented.

So far, after four years, annual weeds have been eliminated, but Canada thistle control continues to be a major stumbling block. The notoriously competitive weed is rampant, and even squeezes into the non-fallow crop rows, he added.

“It works not bad, but the Canada thistle is killing us,” he said. “Until we come up with a means of managing it, this is not really going to help us much. It’s a work in progress.”

Other options, such as plowing to a depth of 10 inches like they do in Europe, is not a viable option for the Prairies. Also, some farmers might balk at the opportunity cost of adding two years of alfalfa to the rotation to fend off the thistle, unless they had a market for the hay or livestock to graze it.

[email protected]

About the author

Comments

explore

Stories from our other publications