NEWPORT, Ark. -- When Chris Tingle is asked about Arkansas’ soybean planting window, he says it can be open from mid-April to mid-July. In 2005, though, things proved a bit different. Some southeast Arkansas growers planted as early as the first week of March.
“Then, on July 25, I was driving through Arkansas County talking with a reporter and he wanted to know the status of the crop,” the Arkansas Extension soybean specialist said at the Jackson County production meeting in Newport, Ark., on Jan. 11. “I looked out my window and saw two grain drills running. I said, ‘Well, we’re about five days from either harvest or emergence.’
Having to run that planting gamut makes Tingle’s job tough. “We have all kinds of problems in soybean production. When you spread the planting window across that many weeks, the problems just multiply.”
Early in 2005, the USDA projected Arkansas producers would plant some 3.1 million acres of soybeans. That follows the trend for the last four years when state bean acreage hit around 3 million acres.
Roughly 68 to 70 percent of those 3 million acres are irrigated. “That still leaves about 1 million acres that aren’t irrigated. In those fields, we’re really at the mercy of Mother Nature, something we saw all too well in 2005.
“The last crop update I saw said we’d harvested 3.03 million acres from the 2005 crop. The average yield was 34 bushels. That’s down 5 to 6 bushels from 2004, when a new record of 39 bushels was harvested. The 34 bushels seemed optimistic to me. I estimated we were down 8 to 10 bushels from 2004. All in all, though, we seem to have squeaked by in 2005. Hopefully we won’t have a re-do in 2006.”
Much of the southeast part of the state had a decent 2005 crop with near-record yields. “But if that region was the Garden of Eden, this part of the state — Jackson, Independence and western Poinsett counties (in north-central/northeast Arkansas) — was the Sahara. It was rough around here. I normally drove through Jackson County at least two or three times a week and it hurt to look out and see the crop being hammered by a lack of rain.
“Drought monitor maps from April through August show Arkansas’s drought progressing from the southwest all the way to the northeast. Much of the state was in a severe to extreme drought through almost the whole growing season.”
In some of Tingle’s research plots, “we waited a month to plant, hoping for a rain. Finally, we just had to shoot some water across the ground to get some moist soil to plant in. We must get stand. Without that, everything else we discuss today is worthless. 2005 was certainly a challenge. And I hate to say it, but 2006 isn’t looking much better thus far.”
Dry weather early in the season can make an uneven crop. Multiple growth stages of the crop can occur, often in the same field. This leads to new challenges.
“Last year, replant decisions were common and calls were tough to make. In some fields, we had soybeans flowering and emerging, side-by-side. The older plants can serve as hosts for things like stink bugs and some diseases before moving into the rest of the crop.”
Another byproduct of the drought was a lot of chloride problems. Especially alarming to Tingle: some areas where problems emerged haven’t historically been troubled with chloride.
“In some fields, maybe for duck hunting, we held over water and didn’t get it off in a timely fashion. If the water was allowed to evaporate and had some chloride, it was concentrated in the top 4 inches of soil. Young beans then took up that salt and died.”
Another thing faced in the dry conditions was charcoal rot, seen in every soybean-producing county of the state. “In dry conditions, charcoal rot can infect the root system and move into the vascular tissue. You can’t tell there are any problems until July or early August when, all of the sudden, plants start dying. Pods are flat and seeds are small — basically from the plant being choked from the inside out.”
The drought isn’t over yet and rainfall deficits are very high. The north-central Arkansas deficit is almost 20 inches.
“My four-year-old daughter got a new kitten at the end of October. The other night, it dawned on me that cat had never seen rain. When it finally rained, that cat flipped out.”
Growth stages and heat
The Arkansas soybean production calendar from April to September shows moisture is needed to get a stand. But the early vegetative stages aren’t as dependent on water. Then, as the crop moves into the reproductive stages, the need for moisture becomes paramount.
“About 65 percent of the crop’s water use occurs once the plants begin flowering. That’s why we saw such a yield decrease in 2005. The reproductive phase was when the state was driest.
“We conducted a variety test in Weiner, Ark., on Scott Matthews’ farm. A weather station was set up to record all the environmental data. Scott caught about 4.75 inches of rain from May to July. And that includes a spike of rain at the end of July — almost too late to do any good. Scott had to irrigate more times than he’s ever done.”
Something often overlooked in growing a crop is temperatures.
“Cotton researchers have jumped on this and how it affects yield variability in that crop. What’s been found is nighttime and daytime temperatures over the last 10 or 15 years have elevated. The increase may have been minor, but they’ve climbed.”
Between May and July, the test on Matthews’ farm showed only four days hit the optimum temperature range for soybean production.
One of the direct impacts from heat — whether day or night — is abortion of flowers. Soybean plants overproduce blooms, normally aborting 65 percent to 70 percent. With additional stresses — especially water combined with heat — they will abort even more. Heat also causes seed size to diminish and the number of pods is hit.
“There’s not much we can do about temperatures. Eventually, perhaps we can get some genetics to help. Right now, about the best way to address high temperatures is to irrigate. As much as we tried in 2005, though, we couldn’t meet the crop’s demands.
“I talked to plenty of people who say, ‘I irrigated my crop five or six times. Why are my yields down?’ Well, I irrigated my test plots 12 times from June to August. But we can’t afford to do that.
There are some simple ways to approach a soybean crop, said Tingle.
• Know how much seed you’re planting.
“Every year I go on calls where there are questions about the stand. Rarely do they know how much seed was planted. That’s a direct input cost, something we have control over.
“If you don’t know how much seed you’re planting, take a little time to figure it out. Trust me, with these input costs we’re facing it’ll be worth your while.”
• Narrow rows versus wide: Arkansas research data has shown that if you have a choice between narrow rows of less than 20 inches or 30- or 38-inch rows, consider the narrower rows.
“We’re seeing an increase in yield in the narrow rows. I attribute that to not only the adaptability of the plants and how they grow in narrow rows, but also to the quicker canopy closing. The canopy reduces weed problems, and we saw this year, it reduces the speed the sun and wind can evaporate any moisture on the soil surface. Ground in narrow rows stayed a lot wetter for a lot longer than the wide rows did.”
• Don’t use unnecessary inputs. “I talk to a lot of producers and some tell me they put some snake-oil on the crop. ‘The guy at the co-op told us we needed it.’ I’ll ask why they took his advice and the answer is, ‘I don’t know. It was just $2 per acre.’
Arkansas produced 3 million acres of soybeans in 2005. “If everyone took that co-op’s advice, it cost $6 million. That’s a substantial investment. Think about that.
“There were also plenty of producers who sprayed fungicides to prevent soybean rust. Why? There was no rust. We had a hard time finding frogeye in some fields.”
The Arkansas Extension Service recommends applying fungicides only if you have a disease at threshold. If a chemical salesman or company says spraying one will make money, “leave an untreated strip and tell them to stand behind it. They used to do that. Our tests have shown that without a disease, you could throw away anywhere from $18 to $24 per acre and not increase yields.”
• Soil tests and fertilizer: Because of high fertilizer costs, many producers are considering not fertilizing soybeans in 2006. They may try to piggyback on what was put out for 2005 rice.
But in looking at soil test levels, “we’re seeing a lot more potash deficiency symptoms. That’s especially true in Jackson, Poinsett and Craighead counties. The silt loams tend to show that deficiency a bit quicker and impact our yields a lot more.
“If you’re going to shave something and not put out a full rate of fertilizer, I’d prefer taking off a little phosphorus. For soybeans, though, stick with the potash. Most of the calls I get on fertilizer problems involve potash.”
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