“A big question, Horton says, is can you kill a rye cover crop without herbicides?” As with most things in agriculture, the devil is in the details. If heavy rye cover is in the soft dough stage, and it’s rolled down, it will stay down, he adds.

“If rye is in the flowering stage, whether it stays down or not can go either way. If there is good news to failing, with killing rye cover crops, if you fail, you will know it soon,” Horton says.

If the rye is rolled too early, it can be a season long failure for the following organic crop. It doesn’t have to be that way, because the rye will eventually dye, but it will suck up a lot of moisture before it does. In years like last year, when too much moisture was a problem, missing the optimum rolling date was not a big problem.

Always roll the rye cover crop down in one direction. Growers should expect some lodging problems, but so far in three years of testing, it hasn’t been a big problem with rye cover crops ahead of soybeans,” he says.

With seeding rates on rye up to 90 pounds per acre, getting soybean stands in the heavy mulch can be an issue, but Horton says that even losing some soybeans in the mulch has not significantly reduced yields in his three years of testing.

Getting a good, early stand of soybeans in the rye mulch is critical to good weed control and ultimately in getting a good soybean yield.


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How soybeans are planted into rye mulch can have a big impact on weed control. Weeds find a place to grow like water finds a leak on a roof — you don’t always know why, but it always seems to happen. A common place for weeds to get a start is in the slices made in the soil by row cleaners.

“You don’t ever want to use row cleaners in a heavy mulch cover crop, because that’s the ideal place for the most damaging weeds to get a start,” Horton says. “Regardless of what a machinery dealer tells you, the slicing coulter must have a smooth edge,” he adds.