WHEN MERLE Anders came to Arkansas three years ago he began work on crop rotation. What works best? Why and how?
“Farmers don't buy and sell farms every year, but they do rotate crops. A lot of times they do this because certain crops in certain sequences on certain soils perform very well,” says Anders, a University of Arkansas rice systems agronomist.
The biggest comparison Anders and colleagues are currently studying is that between conventional and strict no-till crops.
“The reason we're looking at no-till so closely is, given the current economic environment, I don't see any other way to save big money. I don't think Deere will decrease machinery costs or that fuel costs will dip way down. Switching tillage, however, offers an opportunity to save money and do a bit better on the profit line provided you can keep yields up,” says Anders, who spoke at the Monsanto Center of Excellence Field Day on Orelan Johnson's Coy, Ark., farm.
Another reason is that no-till directly addresses quality issues involving soil, air and water. In terms of air, by going to no-till the perpetual spring dust storms on the Grand Prairie are lessened. Also, it's well known that water quality increases under a no-till regimen.
“Soil in the Grand Prairie was once near 3 percent organic matter. It's liable to be less than 1 percent now. That has many implications in standability issues, long-term production and so forth. No-till may not give you an instant return, but under such a system, the soil will benefit rapidly.”
Anders' work indicates that by going to no-till farmers can save water. Lack of water (especially in the Grand Prairie region) “is certainly an issue that farmers face daily. One way to address it is through reduced tillage.”
Anders says he's quite keen on wildlife management and how it can fit into tillage systems. No-till fits nicely. For example, a farmer can put levees back up, impound the water and leave it there. That results in an off-season “triple whammy”: the farmer can hunt, he can sell duck blinds, and at the same time also decompose much of the organic material in the field. The decomposition is especially beneficial when working after rice.
“In tests, we put out two fertility levels — one the recommended level and the other an enhanced level. I did that for two reasons. The biggest reason is, after talking to farmers, I found that most say they apply more fertilizer than is recommended. They might do that for a reason we haven't picked up on. But it can also have a negative impact or be benign and therefore be money down the drain.”
Farmers considering changing tillage systems shouldn't expect the variety they've been using conventionally will continue to be tops. Instead, they must search out the variety with the best genetic material to fit the new system.
“How do you do that? Well, I'd like to say that in rice we have all the answers. We don't. Of the varieties I'm working with currently, the one I'd recommend for stale seedbed or no-till would be Wells. I've found it to be vigorous, robust and it gets out of the ground well. It has an aggressive root system,” Anders said.
“One thing we've done with our weed control in rice is apply Command with Roundup®. Basically, we look at the crops after spraying that. If it looks good, we leave it alone.”
If there are sedges, Anders uses Permit® herbicide. If there are other types of grasses left, he usually applies Facet® herbicide or a propanil-based compound.
Results on rotations
If you compare continual rice with rice/soybeans or rice/corn rotation, you get about a 35-bushel loss in continual rice. Anders' guess is that farmers growing continuous rice are adding “a bunch” more fertilizer.
“On continuous rice, we did find that weed control is a little easier than we originally thought,” he said. “Once you modify equipment and get the drills where they should be, the varieties will be fine. We haven't been able to get yields with the fertility levels we're using, though. Hence the belief that fertility levels must be bumped in a continuous system.”
Think outside the box, says Anders. In moving to no-till, a farmer must change his attitude almost completely.
“An example of how that works is the first year we did this, I saw DTN and a front was moving across Oklahoma towards us. I figured I'd go ahead and get the beans planted quickly.”
The front hit, it rained for a week and the beans rotted because the soils had a bunch of organic matter and didn't dry. If you're no-tilling, soils stay wet a lot longer, says Anders.
“So the next time a situation like that occurred, I just had a beer and waited for the rain to end. The beans came up just fine.”
If a farmer wants to no-till he should start planning a year out. One reason is the fields he's been farming conventionally are probably rutted and need some work.
“Part of this is getting to know farmers who have been no-tilling themselves,” Anders said. “They can help you through a lot of problems if you're willing to be a student for a season or two.”
For no-till, a lot of the conventional machinery farmers have will work with only minor adjustments, says Anders.
“The biggest help we found are closing wheels. I didn't think it would work, that there would be seed on the surface. It works just fine, though.”