When the drill gets parked, it’s time to hook up the land rollers.
Ken Wall, grow team advisor at Federated Cooperatives Ltd., says there are two reasons why you’d want to roll lentils (and other pulse crops); one of which is to smooth out the ridges from seeding.
Lentils in particular are a low growing pulse crop, and getting all of the crop off requires lowering the combine header pick-up height at harvest, making a smooth surface very important.
The other reason to roll lentils or pulses is to push stones and rocks into the ground, which protects the combine from damage. In addition to these reasons, and according to Saskatchewan Pulse Growers, rolling can also reduce the risk of down-grading a harvest sample with earth tag.
“Ideally, you want to roll your lentils right after seeding, especially before crop emergence,” says Wall. However, if a rain event occurs right after seeding, rolling soil that’s too wet can cause excessive compaction or crusting. Another caveat for rolling right after seeding is if the soil is too dry, as rolling could pulverize protective stubble or soil clods in the field that could blow away.
So when is the best time to roll? Wall says that land rolling shouldn’t be done right when the crop is about to emerge, as it can cause cause mechanical damage.
“Once they’ve emerged, you can actually roll them up to about the 5-leaf, or 7-node stage,” says Wall, and he says to wait till the afternoon or a warmer part of the day when the crop is kind of limp, as they’ll be less prone to damage then. Wall also says to consider rolling when the leaves are dry, because if the leaves are wet, you risk spreading disease. Further to that, if you damage the plant, disease then has an entry point to infect the plant.
If herbicide timing is close — say within three days or so — Wall says to consider forgoing rolling altogether, because any risk of damage to the crop right before a herbicide application will really stress the crop out. Wait three to four days after rolling, before doing a herbicide application.
Catch the full conversation between Wall and Kara Oosterhuis below: