Seeding Tools Go Head to Head

Two top seeding tools ‘duked’ it out on this Manitoba seed farm, putting in 320 acres of soybeans in 2016. The winner…?

By John Dietz

Which seeding tool is best for soybeans and best for your farm?

Manitoba seed grower Brian Nadeau, at Fannystelle, asked this question and had the tools to do the testing in 2016. He put in a half-section of new NorthStar dicamba-resistant soybeans, NSC Starbuck RR2X, using his 60-foot White planter for half of the field and his new 60-foot 3720 Bourgault air drill for the other half.

The White 9936-20 series corn-soybean planter was set up at 20-inch row spacing. It uses double 15-inch discs for openers. Nadeau had used it for three seasons ahead of the 2016 trial.

The Bourgault air drill and cart was new in 2016. It uses 10-inch spacing and is made for cereals and canola, rather than row crops. It uses a single 20-inch disc opener.

“We went to the 20-inch planter because it can do corn and soybeans very well. It’s an excellent, precision planter,” Nadeau says. “We went to the 10-inch Bourgault for all our cereals and canola. With it, we have the mid-row bander. It’s also an excellent tool.

“My question was, do we need both? I wanted to compare the 10-inch row that every other farmer has with the results from a planter. The planter should give us more yield.”

Having precision guidance on the farm and seeding equipment matched at 60 feet gave the grower a unique opportunity.

During the third week of May, he put the two systems side by side on a square, nearly level, 320-acre field that had been in oats in 2015. The air seeder set up the baseline and made the outside rounds.

“Once they had the base-line set up, the planter just picked Line 2, Line 4, Line 6, and so on. Then the drill came between and planted the other lines. Once they started, they were beside each other and they would keep on moving over. Through the whole field they were side by side,” he says.

Planting depth was set to match, at one-and-a-quarter inches. Seeding rate in the planter was targeted at 160,000 seeds per acre and 195,000 for the drill. The seed was treated. Liquid inoculant was applied in-row with the planter while the air drill used granular inoculant.

Nadeau noted the soil disturbance was slightly more with the drill. His impression was that the planter had slightly better row packing.

Meanwhile, agronomist Jason Voogt, had started to monitor the whole project for Nadeau. Voogt has an independent crop consulting company at Carman, called Field 2 Field Agronomy Inc.

“Field conditions were quite dry when we were planting. Both seeding systems were struggling, trying to find that happy medium for hitting decent moisture,” Voogt says. “It wasn’t long after, maybe another 10 days, until we started getting some appreciable rainfall to aid germination.”

The field has typical Red River clay and only surface drainage. Half-way through the growing season, it struggled with excess moisture.

“There were saturated soil conditions for a good part of the season,” Voogt says. “Later in the summer, there was hail in the southwest corner of the field. When we did the yield calculations, we only looked at the more uniform areas of the field.”

Voogt checked the seeding depth. Both systems were well matched, but the planter probably had a little more consistency on seeding depth. They agreed that both systems worked very well in maintaining uniform depth and spacing.

He compared the singulation, the spacing of soybeans in the rows. He says, “The spacing between plants in the rows is always a little more accurate with the planter, but that may not be as crucial with soybeans as with other crops.”

Weed control was excellent at the beginning of the season. An early pre-emergence application of XTendiMax burned off everything that had been growing. The field stayed black, allowing the crop to get established before the first weed growth began two to three weeks after planting.

Emergence was almost even, although favouring the 20-inch planter rows by one or two days.

“I don’t think the spacing uniformity led to later differences,” Voogt says. “Soybean has a little more elasticity [than corn] in branching or compensating. You were able to see it in the narrow-row spacing strips. Once the plants got past flowering, you got canopy covering all areas of the field.”

For weed control, the only challenge was from volunteer glyphosate-tolerant canola. The agronomist says, “Initially, the pre-emerge application of XtendiMax did hold the canola down, did hurt it. After a while, it broke through, but all the other weeds were controlled very well.”

The two were wondering whether the narrow rows would see more disease in August. There is a school of thought that, in warm moist conditions, the more open air flow on wide rows will be less favourable to white mould trouble.

“Because the 10-inch rows had little gaps, I definitely expected to see more disease there,” Voogt says. “This was a good lush, aggressive variety later in the season, so we got really good growth and canopy closure. This variety stands very well. We did not have any major lodging issues, and because it stood very well, it helped prevent the onset of white mould disease in a canopy situation like that.”

He looked, but determined that the level of white mould was about the same in each type of row spacing. The only other disease was brown spot, at a level that was insignificant.

Senescence was next. The natural drydown, if anything, had a two-day difference. Treatments with narrow rows were a little later in drying down completely, but everything did mature on time.

At harvest, Nadeau used one combine with a 40-foot header to take off the row spacing trial. He harvested the centre of each strip, then put it through a weigh wagon.

“Nobody noticed a lot of difference for harvestability between the two row spacing treatments,” Voogt says.

“And, at the end of the day, you didn’t see a lot of difference in yield, either. It was about one bushel, plus or minus, between the planter and the air drill,” Voogt says.

The results for Nadeau are useful, but limited, he adds.

For another variety, another season, another farm, it probably would have been different.

“To get your own answers, you’d have to do a different trial on a different soil type with different varieties,” Voogt says. “To get a better sense of the comparison, I would like to do this multiple years, on multiple fields, with different varieties.”

As for Nadeau, his planter may be for sale. He says, “The final difference was one bushel from the planter. I would think hard about purchasing a planter, if the only reason is getting better yields.”