Rains, delayed planting, replanting defined 2019 soybean season

A lot of marginal ground and flooded acres did not get planted or had to be replanted in 2019, which kept the average soybean yield around 50 bushels per acre across Mississippi, Arkansas, and Louisiana.

“I think that estimate may be high for our state,” says Jeremy Ross, Extension agronomist, Soybeans, Crop, Soil and Environmental Science, University of Arkansas System Division of Agriculture, one of three speakers providing soybean updates, at the Tri-State Soybean Forum held recently in Dumas, Ark.

“Arkansas producers planted 2.7 million acres of soybeans last year, the lowest acreage since 1961.”

Rains across Arkansas began in the fall of 2018 and continued frequently, not allowing fields to dry until 2019. “That delayed everyone’s planting,” Ross says. “We only had 50% of the entire soybean crop planted by June 1. You have to go back several years to find when planting was delayed that long.”

Louisiana update

Wet conditions caused late planting across Louisiana, too. Many producers reported yields were down 10-plus bushels per acre from normal. “The local FSA office estimated our state planted 866,258 acres and we had over 110,480 preventive planting acres due to the wet/cool spring. The wet/cool spring also resulted in a high number of replanted acres,” says Josh Copes, agronomist, LSU AgCenter, who gave report for his state.

Copes said David Mosely has been selected to fill the vacant soybean specialist position.

Rain from Hurricane Barry hampered soybean development after the Category 1 system made landfall 150 miles west of New Orleans on July 13 and left 20 inches of water in some parts of central and south Louisiana, leaving many soybeans covered in water for an extended period.

Hot and dry weather throughout August and September stalled soybean growth again, reducing seed size and weight. “I had one consultant tell me our soybeans seemed to go from R5 to R6.5 in two weeks, skipping R6,” Copes says. “We also had some manganese nutrient deficiencies, and lower seed quality and vigor was prevalent in soybean varieties this past year. Soybean green stem was seen in most of our Official Variety Trials (OVT) across the state.”

Trey Price and Boyd Padgett identified tap root decline in the northern portion of Louisiana, especially prevalent in fields where soils were not tilled and farmers grew soybeans behind soybeans.

Foliar diseases were light to moderate. Southern green stinkbugs and brown stinkbugs were the primary pests in 2019 with high populations reported around the R5 stage. “Sebe Brown told me red-banded stinkbugs were hit or miss. They showed up early in the season, disappeared, but moved back in some areas during pod fill,” Copes says.

“Daniel Stevenson told me growers maintained good control of weeds last year using two applications of glyphosate, plus one of the dicambas, but he strongly advises against relying on these new technologies alone for control. Overlaying residuals is a must. If you can keep fields clean for five weeks after planting, research has shown yields will be maximized.”

Mississippi update

Most Mississippi soybean growers started planting in early April and estimates pedged potential acreage to be over 2 million. “We’ve had between 2.1 million and 2.3 million acres the last several years, but we got nowhere near that number in 2019 because of the widespread flooding in the south Delta,” says Trent Irby, Extension soybean specialist, Mississippi State University, who spent time from April through early July helping farmers make replant decisions.

“We had some easy problems; the harder problems were half-flooded fields where growers were forced to terminate good portions of those fields and start over to be able to manage and irrigate efficiently.”

Favorable rains toward the end of June and into July turned the crop around but hot and dry conditions at the end of the growing season took a toll on final yields. “Our soybean acreage should rebound in 2020 and growers are looking forward to a more optimistic year,” Irby said.

Source: Brad Robb, Delta Farm Press