Four years ago, Merle Anders and colleagues began a long-term study on a series of rice-based crop rotations. In various combinations, soybeans, corn and wheat have been meshed with rice in research plots. Anders (who spoke at the Monsanto field day in Coy, Ark., on July 24) is studying the rotations in both conventional and conservation/no-till situations.
“In a general sense, with con/no-till, don't expect to have your yields double,” says Anders, cropping systems agronomist at the Arkansas Rice Research Station in Stuttgart. “We haven't been able to do that, and I doubt anyone has. Instead, what we're looking at is achieving the same yields — perhaps a bit better — as you'd normally get with conventional tillage. We want to achieve those yields while spending much less time and money on the field.”
The benefits of con-till are many. Among things cited by Anders:
- The organic matter will improve in the soil. What difference does that make? “Well, with rice, upwards of 80 pounds per acre of nitrogen comes out of the organic portion of the soil. Compare that to perhaps 50 pounds if using fertilizer alone.”
- Soil structure and aggregation also improve considerably. “We don't have to flush rice.”
- Root penetration improves.
But can you make money and what are the problems associated with con/no-till systems?
“I'll run through some issues we've had to deal with. Many of these things will be based on rice — although some things also pertain to soybeans.”
The trick, Anders has found, is if a producer wants to employ a con-till system, he must plan well in advance. “You can't go into a field that's been rutted up and expect to make a go of con-till. It won't work and you may not even get a stand up.”
Other things to consider:
- In winter, Anders says, it's generally better to have a field flooded. This helps with the decomposition process.
- In moving to a con-till system, it's very likely you'll be able to get rid of some machinery. The tools you keep, though, need to make as few ruts as possible. This point is key, says Anders
- With rice, “we find the planter is of utmost importance. With a rice/soybean rotation, which a common in the Grand Prairie, producers can usually get by fine with a standard planter with a couple of modifications. Closing wheels are well worth the money.”
With continual rice, Anders sometimes runs into problems with dry seeding. The reason is — assuming it isn't burned off — “you're looking at about 8 tons of matter lying there every year. That builds and builds. How to deal with it? In most cases, we suggest water seeding.”
Using a con-till system reduces the amount of flushing needed drastically. In fact, overall water use will drop. “We're running 1 to 4 inches less irrigation per seed. There's probably 30 inches of irrigation used to grow a crop.”
Varieties Anders has looked at include Wells. “I really like this variety because it has an ability to get a nice stand under difficult conditions.”
Command and Facet have been used for weed control. Until a couple of years ago, the same rates were used on both tilled and no-till fields.
“Suddenly, we found with the increased organic matter in the soil, Command was a little less effective.”
What happened, he says, is that an organic soil was created on top of mineral soil. That caused a bit of a problem. So Anders increased the Command rate. That led to very good weed control.
“We did have another dilemma this year. On our no-till we found some signs of Facet toxicity. They were quite bad in plots we were rotating with corn. So we dropped Facet rates way down and might take it out completely.”
In general, once you get the weed control tweaked in con-till rice, it's going to be much easier on your wallet. You'll also have much fewer problems with red rice, says Anders.
Anyone who doesn't no-till soybeans behind wheat is probably missing out, says Anders.
“We consistently find our yields are better where we no-till beans after wheat. I think one key is to get a combine with good shredder/spreaders. We need to get the material spread out so it can be easily planted into. Slow down a bit with the planter, get the seed where you need them and you'll have much better luck.”
Using standard soybean varieties with con-till systems works very well if a field has good drainage or bedding. “You must watch a field and not go in too early. Be patient.
That applies to rice also. If you plant rice into no-till conditions at the same time you plant conventional tillage, then expect the no-till crop to be about five days behind. And expect your neighbors to laugh at you for a couple of weeks — they can't see the plants and think you've wasted time. If you want to check that no-till crop, get out of the truck because, from the road, it won't be obvious it's emerged.”
As with soybeans, corn needs good drainage, too.
“In con-till corn, we've found that applying fertilizer later really pays off,” notes Anders. “The final hit just as corn is flowering pays big dividends. We aren't increasing rates, just putting them on a bit later.”