SIOUX FALL, S.D. – The sins of last fall may be back this spring as the growers face another potentially wet spring. Due to last year’s wet fall, there is a strong chance of compaction issues this year, not to mention tillage that did not get done and diseases hiding in the soil.
“Harvesting in that wet weather, we definitely compacted things in areas that are tracked up,” said Roger Plooster, agronomist with Golden Harvest, during a recent phone interview. “Unfortunately, we are going to see issues in those areas for the next two or three years.”
Getting tracks out of a field is just a waiting game. Tillage is not going to remove that compacted soil. General freezing and thawing of the soil will slowly break that compaction up over time, but it will be important to avoid adding any more compaction to the fields.
“Just try to be as patient as we can, not get out there too early with the heavy tillage equipment,” said Plooster. “Wait as long as we possibly can to get out there and do that last trip of tillage or in some cases, unfortunately the first trip of tillage, to try to avoid compacting it that way.”
As it is already the end of April and May 1 is just around the corner, having patience may be a challenge.
For soybeans, the optimum planting window is May 1 to around May 20.
“Of course, we can get some good yields before and after those dates, but that is the sweet spot for planting,” he said. “The key is early canopy.”
Earlier planting usually means a faster canopy, but there are other factors that affect a quick canopy. Emergence for one and seedling health for another.
Planter speed can have a big impact on even emergence and getting a uniform field.
“We have got about nine years’ worth of Golden Harvest agronomy research data that shows at three miles per hour planter speed we are getting less than 5 percent of the soybean plants emerging late, and by late, five to seven days late,” he said.
Now, given that the planting season seems to be getting shorter every year, the mentality might be to increase planter speed a bit, just to get the seed in the ground.
“When we bumped that planter up to seven miles per hour, almost 15 percent of the plants are emerging late,” he said. “That can obviously give us canopy issues, but also it is yield reduction.”
The second important factor to canopy closure is seedling health. Last year was a wet year, and fungi thrive in warm, wet weather.
“We kid around at a lot of meetings that the odd years are the white mold years and so 2019 is going to be a white mold year,” said Plooster.
There is some logic behind the idea of odd years being white mold years. Remember, 2015, was a bad white mold year in southwest Minnesota, then again in 2017. In a regular corn/soybean rotation, soybeans will be planted into those same fields again this year.
“I strongly urge that growers do pay attention to white mold tolerance when selecting their soybean varieties for 2019,” he said.
Seed treatments and inoculants will also be crucial this season.
Treated seed will be able to get a quicker start in potentially less than ideal field conditions and the fungicide will protect that seedling.
In most years, there is more than adequate amounts of rhizobia in the soil from the previous soybean crop to get good nodulation for the new crop, so inoculating soybeans may not be necessary.
This year, that might not be the case.
“The rhizobia involved in nodulation on soybeans does not last very long in saturated or flooded soils,” he said. “Over the last couple of years, almost every field has had pretty severe flooding.”
A quality inoculant this year may go a long way, toward getting good nodulation on the roots and good nitrogen fixation.