Arkansas soybeans suffering heat, drought

Much of the Arkansas soybean acreage is struggling and a large portion hasn’t even been planted. “There are some serious problem areas,” says Roger Gipson, Pioneer agronomist. “In the White River bottoms — and even outside the flood zone like in Jackson County —thousands of acres are yet to be planted. It hasn’t rained since the river dropped over six weeks ago.

“I was just in St. Francis and Crittenden County (in east Arkansas) and there are some hot spots where growers have half stands, at best. They aren’t sure how to proceed. Growers south of Walnut Ridge and Lawrence County are also having major issues with the bean crop.”

The Arkansas soybean crop is at least several weeks later than normal. “But a lot of acres haven’t been planted. Pray for rain, man.”

Lanny Ashlock, Cullum Seed agronomist, is “pretty pleased” with most earlier-planted soybeans. Overall, the April plantings “look pretty good … and many of the growers with early plantings have scheduled or are scheduling fungicide and/or insecticide applications.”

However, the bulk of the full-season crop is much more variable. The spectrum includes “some very strong fields (and some) weak fields due primarily to variation in soil moisture at planting. A common denominator with a considerable portion of the full-season plantings is that the beans are very young, often the same as double-crop plantings.”

A lack of soil moisture has made double-crop soybeans a difficult proposition. Even so, “it’s impressive to see how hard our growers are working to get the double-crop planted and up to stand. Many are bedding and either planting dry and trying to water them up or irrigating and then planting into moisture (which seems to be more consistent).

“It’s a hard way of doing business — it appears that we’ve got poly-pipe strung out everywhere — but we are slowly getting the 2008 Mid-South crop planted. In many cases, the resulting stands are on the thin side but usually acceptable (although) there are exceptions.”

If it had not been so dry, many producers would have their double-crop plantings done by July 1. That won’t happen, now. “A substantial amount of our double-crop and full season beans are yet to be planted — it’s a guess, but I’d say at least 200,000 acres.”

What about seed quality issues this year?

“Going in, we knew 2008 would be a challenging year for seed quality,” says Ashlock, formerly the Arkansas Extension soybean specialist. “Of course, I work for a seed company now and I know how (Cullum) tried to provide a product that soybean growers expect. I’m sure the other companies did the same.

“Overall, the companies provided an adequate product, but I think most would agree that the overall bean seed quality in the Mid-South was a concern in 2008, especially with late plantings. The difficulty in getting a stand with the double-crop or late plantings has been compounded some because the seed was planted deeper than normal as growers tried to put it into moisture. This resulted in additional stress on obtaining good, uniform seedling emergence.”

John Rupe, a plant pathologist with the University of Arkansas, says the problems seen in soybean seed aren’t a surprise. Reports in early 2008 showed “seed lots didn’t necessarily have low germ, but they did have low vigor. As long as planting conditions were good, we didn’t see much stand trouble. But as soon as there was a little stress on the seed, vigor trouble really came to the forefront.”

Now, Rupe is “having problems with soybeans, just as growers are. One of my late-planted tests is a bust — not enough seed came up. Another cultivar planted at the same time nearby has a good stand. That points to a seed quality issue.

“But we’re also planting under rather stressful conditions. I suspect (the stand problems) are a combination of environmental stress and seed vigor problems.”

Rupe recently checked soybean fields in a swing through the Delta. “Several fields in southeast Arkansas have borderline stands. In most, plant numbers aren’t low enough to replant, but they’re close.”

Soil texture seemed to play a part. “In the fields we saw, the heavier, clay soils tended to have better stands than the sandier soils.

“We dug up seed. Lots of it had germinated but didn’t have enough ‘oomph’ to get to the surface.”

Most of the soybeans Rupe scouted were irrigated. “But this isn’t the time of year you want to be irrigating. You can hurt stands by trying to irrigate beans up. Of course, that’s better than not getting a stand. There are certainly a lot of growers flushing fields to get beans up. It isn’t just a dryland/irrigated issue.”

What do current conditions portend — if anything — for next year’s seed supply?

“I don’t think it’ll be a big factor for what’s harvested this year,” says Ashlock. “What will impact seed quality this fall will be the same thing that impacted it last year: environmental conditions near, at and following, seed maturation. If it cools off and is reasonably dry from the last week of September and October, we should have very good quality seed.

“When we harvested our seed production in 2007 we were somewhat apprehensive because of environmental conditions. It was very warm and humid with many showers occurring during seed maturation and at harvest — not only in the Mid-South but in many areas of the Midwest.”

Even at this late stage, Ashlock encourages growers “to take your time and ensure a stand. At least in the northern half of the Mid-South, if we can plant by July 10 and get a stand, there’s still pretty good yield potential with good irrigation and pest management practices. The dryland fields will typically suffer the most.

“Once we get the crop up and growing, I’m confident that given half a chance, growers will be able to push it and make some good things happen.”

The soybean crop can compensate for thin stands, “especially on irrigated, lighter soils. That’s why we’re better off going with a thinner stand if it’s uniform (50,000 to 70,000 plants per acre) — even a stand that’s thinner than most growers are comfortable with.

“That’s often better than going in and tearing up that thin stand, replanting and hoping what comes up will be better. Of course, (by replanting) the risk is you could lose everything.”

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