No-Till Wheat, Soybeans Make Great The Grand Prairie of Arkansas is noted for its rice, soybean, small grain and duck production - and now beds.
Coming on strong in recent years: the practice of growing wheat on 40-60" beds, then no-till drilling soybeans. Savings in labor, machinery, irrigation and deer damage, and an increase in soybean yields, are given as the chief motivators in moving to 7.5" rows.
The most popular crop rotation is one year of rice and two years of soybeans with a wheat crop between the soybean crops.
For the past seven years, Wilbur Joe McLain of DeWitt has been no-tilling his late-planted soybeans into wheat stubble and residue that he doesn't burn. He says this wheat-soybean program has enabled him to plant his doublecrop soybeans 1 11/42 to two weeks earlier and into better moisture.
"Our rotation works on thirds - one-third of the entire acreage is devoted to rice, which follows the harvest of wheat-soybeans, the residue of which is worked into the soil in the fall," says McLain.
The rice is planted stale seedbed the next spring. After the rice harvest the following spring, this third is planted to full-season soybeans and cultivated in conventional 30" rows. In fact, the cultivator makes the beds for the wheat and drilled soybeans that follow.
McLain is able to use the proper rice herbicide and then follow with a yellow herbicide or Dual with Scepter or Canopy XL. This is an excellent program for johnsongrass control in soybeans, he says.
"We no-till the wheat on the beds. When we follow with soybeans, we're able to use entirely different herbicides - a burn- down with Roundup Ultra a day or so behind the planter and then Conclude, Poast Plus or Assure (the last herbicide for the year) in 10-14 days."
During that three-year rotation, McLain controls weeds with herbicides from three chemical families.
"With this program we get away from any kind of resistance from weed pests," he says. "We have obtained excellent weed control from both the Roundup and the straw; the latter also tends to conserve moisture and in turn increase soybean yields."
McLain says his intensive farming program has reduced soil organic matter to less than 1%. "However, by saving our straw we have increased the organic matter, not all that much, but to a range of 1.5 to 2.5%.
"Growers who burn the residue from their wheat fields may save a $10 application of Roundup, but they destroy much organic matter at the same time," says McLain. "And you look like a real hero when you have no-tilled your soybeans into wheat stubble and residue, and the weather turns very hot and dry as in the year 2000."
McLain irrigates every middle of his 40" beds with poly pipe, applying about 2" of water every 10-14 days. His slopes range from 1' per 300' to 1' per 1000'. On steep fields, the straw holds most of the soil in place, he says.
"We first used gated pipe in this new program. But poly pipe has made as much or more contribution to the success of the no-tilling of soybeans on beds as any other factor."
Shawn Hudspeth, also of DeWitt, grew 1,850 acres of soybeans last year, 1,250 acres of them doublecropped behind wheat. He plants doublecrop soybeans on beds, but prefers to grow wheat on flat ground.
"After the rice harvest, we burn off the fields, tear down the levees, float the fields and plant the wheat flat," says Hudspeth. "Over the years we've learned that we take away 5 bu of wheat per acre by planting the small grain on beds."
He sets up his beds just after the wheat harvest, in late May or early June.
"In this way we experience faster germination and growth of the seedling soybeans," says Hudspeth. "In the past, when we burned off the wheat and no-tilled the soybeans into the beds, we had problems getting the young soybeans going in these hard `crawfish' soils and also experienced more weed problems."
Hudspeth row-waters about 90% of his soybeans. He says soybeans irrigated like rice with levees and floods don't yield as well as those watered down the furrow.
"When we see the need to flood-irrigate soybeans, we could destroy as much as 10% of the stand, depending on the slope of the field. We've found that watering our soybeans with levees can decrease yields from 5 to 10 bu/acre."
David Neal and his son, Charles McKenzie, know how to grow soybeans. Their full-season beans normally yield about 60 bu/acre; their doublecrop beans, about 50 bu/acre. They like the savings they get by no-tilling the soybeans in 7.5" rows, as opposed to planting 30" rows and cultivating.
"However, one of the major reasons we switched was the heavy deer population we `enjoy' in this part of the world," says David.
He says deer stroll down the middles of conventional soybean rows, eating a row all the way to the end.
"But when they enter a field of broadcast soybeans, they pick or graze as they wander all over the field," says Neal. "We've had much less yield reduction from deer during our three-year experience with drilled soybeans."