Planting rice in a furrow-irrigated system rather than the traditional levees used around the world is one thing. Planting row rice into a standing, green cover crop in the middle of a rainy spring can be quite another.
Ryan Sullivan, one of the partners in Florenden Farms near Blytheville, Ark., described how he and his father, Mike Sullivan, accomplished that task during a stop on the Mississippi County Irrigation Field Day tours of their farm Aug. 5.
“Typically, the drill is the next thing to follow the combine as we’re mostly no-tilling the row rice,” said Ryan Sullivan. “Last fall the combine cut more ruts than I would have liked to see going straight no-till. So, in this field, we ran a Kelly Diamond Harrow when we had a little dry spell in March. We ran the Kelly Diamond and planted the rice a week or so later.
“We ran a bedder-roller behind the drill. Basically, the Kelly Diamond didn’t take out the beds, it just sifted the residue around and smoothed them out a little bit. The beds were still under there.”
Sullivan said he doesn’t run a bedder-roller prior to planting “because we’ll gum up in the gumbo soils here. We have little irrigation shovels on it, and we’re just barely putting those in the ground, taking out the imperfections in the old middles.”
The rye cover crop that was seeded last fall had grown about as tall as the rice currently in the field, Sullivan noted. “We had some difficulty terminating it. It was already producing seed and was at the end of its life span, which may have had something to do with the problem.”
The Sullivans didn’t try to terminate the rye two weeks ahead of planting as some agronomists recommend because the dead rye plants could turn into a wet, soggy mat that would be even more difficult to plant.
“We have to figure out the best time to terminate the cover crop going into rice so that rye – a grass – won’t compete with the rice,” he said. “We had some competition issues out there – we had some nutrient deficiencies or some kind of interaction that caused the rice to struggle.”
The farmers also had a problem with closing wheels not covering the seed trench because of the difference the cover crops made in the soil texture. This resulted in a poorer stand which allowed some grasses to escape and led to two additional herbicide applications.
They also had to spray for armyworms, which seemed to use the “green bridge” from the still-green cover crops to the rice seedlings.
“We’re going to make it work,” said Sullivan. “Somebody’s going to make it work, and someone may be making it work on a big scale already. We as a group have a lot to figure out on how to make the rice work. I think the beans behind cover crops are pretty easy and can work.”
Next: Ryan Sullivan talks about planting soybeans behind cover crops and the economics of cover crops in rice and soybeans.