LSU AgCenter researchers have shown that adjustments to the width and depth of rows can contribute to boosts in yield for soybean and corn. Their project, based at the AgCenter Northeast Research Station near St. Joseph, has demonstrated a consistent increase in productivity over the past two years.

The standard row width for corn and soybeans in north Louisiana is a single 38-inch row on a 38-inch bed. An increase in yield came after changing the size to two 30-inch rows on top of a widened 60-inch bed, with drainage furrows between.

“We’ve seen about a 12-bushel increase for corn and about an 8-bushel increase for soybeans,” said Dennis Burns, coordinator of the LSU AgCenter Northeast Research Station. “It’s been consistent, and while we haven’t harvested yet this year, we anticipate similar results.”

Burns said there are a number of reasons why the 30-inch row, 60-inch bed production system may be working better than the standard way:

• Seeds are planted with greater spacing than for 38-inch rows.
• There is better light reception for the young plants.
• The plants canopy faster which helps with weed control.
• A shallower bed depth of 6-7 inches allows water to wick sideways into the plants, making absorption easier than in deeper beds (a couple feet) for 38-inch rows.
• There is less erosion of the wider beds.
• It is a more stable platform for planting seeds.

Growers realized 38-inch beds were more stable and easier to plant than 30-inch beds. So, Burns and other growers began to experiment with wider, 60-inch beds, similar to sugarcane fields.

The wider beds created a more stable platform that was more efficient for planting.

“I think that has influenced our yield as much as anything,” Burns said. “We also get a better stand that’s much more uniform — increases yield uniformity.”

Another cost-saving aspect of this system involves soil conservation. The wider bed is very flat and stable, which reduces erosion and complements minimum-till or no-till soils. It won’t wash away, so producers don’t have to add soil the following year.

“If you don't have to rebuild your beds, that saves money,” Burns said. “At the research station we've had some of the same soil for three to four years, even though we have to reopen the furrows every other year.”

Burns also works with cover crops to improve soil health. Because the wider beds are more stable and don’t easily erode, this helps improve soil quality by making it more mellow — that is, finer and more crumbly, not clumpy.

While there are some initial costs to convert tractor equipment, Burns says this production system is well worth it.

“We’ve seen this work consistently, and if you’re going to be a corn or soybean farmer, then you almost need to be planting 30-inch rows if you want to see those increases in yield.”