The story for the first half of 2019 was all about too much rain and wet soils. Weather patterns shifted, and the story in August became about not enough rain and holding on to what minimal rain crops did get.
Steve Gauck was quick to notice while inspecting the Soybean Watch ’19 field during a dry spell in August that residue left from the previous corn crop was helping keep soils moist near the surface. Pulling back residue revealed moist soil underneath the cover.
“That’s a real plus when you get to critical reproductive stages,” Gauck says. He’s a sales agronomist for Beck’s, based near Greensburg, Ind. Beck’s sponsors Soybean Watch ’19.
The Soybean Watch ’19 field was no-tilled into corn stubble with a John Deere 750 drill on June 12. Conditions were good at planting, the operator reported. However, rains started June 15 and it rained for 10 days straight. The field received more than 5 inches of rain during that period.
Early on during the wet spell, the residue wasn’t a plus. In fact, by keeping moisture in the soil, it helped foster conditions favorable for slugs while soybeans were emerging and during early stages of growth. Gauck found slugs when he visited the field the first time less than a month after planting.
“There wasn’t that much damage in this field, but they were there,” he recalls. Two years ago, when the spring was also wet but planting delays weren’t nearly as severe, slugs caused significant problems in some fields, including the Soybean Watch field. It was also no-tilled in 2017 into cornstalks. Slugs thinned the stand in that field. However, even the thinnest spots still had 80,000 plants per acre. The crop made 50 bushels per acre.
“In 2017, it was really a slug year,” Gauck recalls. “In some areas they were so numerous that they caused fields to be replanted. And it wasn’t just in no-till fields, either. You can get them in conventional-till fields when conditions are very favorable for slugs. Fortunately, the problem wasn’t nearly as severe this year.”
Gauck notes that’s the trade-off with no-tilling and having more residue on the surface during the entire season. If you hit a wet stretch early in the year, it can work against the crop in certain cases.
“But it’s a big plus when you get later in the year and the crop moves into the reproductive phase,” he says. “Especially in a year like this one when soybeans were planted late and running behind on maturing, they needed all the moisture they could get to avoid aborting flowers and then filling pods.
“There’s no question that having that residue under the canopy helped hold whatever moisture the field received. It’s all about timing when you get to the reproductive stage, especially with weather. If you can hold on to whatever moisture you get longer, it’s a plus.”