When to roll and when not to roll soybeans, that is the question.
Speaking at the Manitoba Pulse and Soybean Growers recent SMART day in Carman, provincial soil management specialist Marla Rickman said it’s important to wait for the right conditions to avoid topsoil loss.
“Generally you want to be rolling right after seeding, but if it’s really dry — especially after going throughout that seeding pass… then it might be time to hold off,” she told producers at the Ian N. Morrison Research Farm.
“As well, if it’s really wet you will want to hold off because then you have an issue with potential compaction from the roller rolling over it,” she said. “And you might not have a very good-looking field by the time you’re done either, because you are also causing more compaction with the tractor going through.”
During the last few springs, wind erosion has been the primary concern.
“In terms of erosion risk, it’s when it’s really dry, and we’ve seen that in the last couple of springs where we’ve had no rain for a while after seeding,” she said. “And if there is no rain, we might want to hold off and try rolling when the plants have emerged, so that the crop can actually catch some of that wind and slow down the wind speed at the surface of the soil.”
Soybeans are fairly resistant, Rickman added, noting the third trifoliate is a good time to roll if you are rolling post-emergence.
“But we don’t really want to see people rolling past the first trifoliate, because we are worried about some of that stand breakage,” she cautioned, adding very new plants may also be susceptible to breakage.
Farmers should also question whether rolling is really necessary, said Rickman, adding that even large dirt clumps tend to mellow out by the time harvest rolls around, especially if there have been a couple of significant rainfalls.
“If you do really low-disturbance seeding and you have a nice table top, I guess my question is, do you need to roll? Do you already have a flat enough surface to have good harvestability? Or do you need to level that out?” she said. “Those are questions you need to be asking.”
Anyone with stones in their fields will need to roll, but they don’t have to go overboard.
“You don’t have to roll heavy, you just need to roll enough to anchor those stones into the ground a bit,” she said.