To use conventional tillage or no-till in rice production? That's a question some farmers are asking.

Brad Watkins, an agricultural economist with the University of Arkansas Cooperative Extension Service, has studied data over the last two years from research sponsored by the Arkansas Rice Research and Promotion Board.

The research is based on a long-term rice system study conducted by Merle Anders, agronomist at the UA Rice Research and Extension Center near Stuttgart, Ark. The study indicates that conventional tillage in various rotation schemes is more profitable, Watkins said. But, he adds, that's not the end of the story.

“Conventional tillage makes a field vulnerable to water and wind and requires a number of mechanical operations which can be fairly costly. No-till refers to planting into unplowed soil. It can reduce labor and machinery costs and reduce soil erosion. It improves the organic structure of the soil.”

He said the long-term study, which now has data for 2000 and 2001, is looking at three rotations: continuous rice, two-year rice soybean rotation and two-year rice corn rotation.

The preliminary data shows that conventional tillage produces greater gross returns than no-till in all rotations, Watkins said. “The no-till system tends to produce less returns in all rotations than conventional tillage.”

According to Watkins, the rice-soybean rotation with conventional tillage produced the highest returns. The rice-soybean system tended to have fewer costs than the other systems because soybeans have fewer production input costs.

According to the study, the average cost for conventional tillage with two-year, rice-soybean rotation is $264 per acre. The gross return is $419 and the profit is $155.

The average cost no-till rice in the same system is $275 per acre with a gross return of $362 and a profit of $86.

In the rice-soybean rotation, no-till relies heavily on herbicides. That cost outweighs any reduction gained by eliminating plowing operations, according to Watkins.

No-till costs for continuous rice and rice-corn rotations are less than with conventional-till, but the yield and profit are also less.

Watkins noted that research into no-till indicates that there are potential yield benefits later on, perhaps within four to 10 years.

“That mainly occurs because of improvements in the soil. The organic content of soil over time improves with no-till, and the soil gains better water-holding capacity. Basically, the soil structure improves over time.”

Watkins said the question for farmers might come down to: “Do I want to lose some short-term yield potential for potential long-term benefits?”

Factors other than net returns might make a farmer consider no-till rice, according to Watkins.

“Water quality is likely to have a strong effect on rice management practices in the near future,” Watkins said.

He said the Environmental Protection Agency might mandate that rice farmers change some practices to reduce the amount of runoff sediment into east Arkansas streams. No-till is a proven, effective method for reducing soil erosion.

Another factor is water quantity. No-till offers water savings, which becomes more important as groundwater levels decline in eastern Arkansas.

“There is a potential for water savings in the early stages of planting with no-till because the ground tends to hold water better,” the Extension economist said.


Lamar James is an Extension communications specialist with the University of Arkansas.