When the season's yields are finally tallied, it's likely corn and soybeans will set records in Louisiana. “And we aren't talking about breaking the record by a bushel,” says David Lanclos, LSU AgCenter corn, sorghum and soybean specialist. “We're talking about beating old records by huge percentages.”
USDA predicts Louisiana's average corn yield will be 170 bushels per acre — 22 bushels better than the state's previous best.
USDA also predicts Louisiana's soybeans averaging 40 bushels — 5 bushels better than the previous best set just last year.
“Those yields are phenomenal and there are many reasons we're seeing them continuing to jump,” says Lanclos, who spoke at an Oct. 30 production meeting at Dean Lee Research Station in Alexandria, La.
“I believe the key this year was simply environmental. We had optimal growing conditions nearly statewide. When we have some dryland corn yields coming in at 210 or 215 bushels per acre, that's obvious. With cooler pollination temperatures and optimum rainfall, yields were bound to be good.”
This year, five grain sorghum hybrids were tested in LSU's core block study. “There was a fairly tight data set. In those tests, Dekalb 5367 led the way followed by Pioneer 84G62 and Terral 96H81.”
Besides the three varieties listed above, Lanclos' “best bet” list for 2008 also includes Asgrow A571, DK 54-00, Dyna-Gro 780B, and Terral 96H91.
“Dekalb 54-00 and Pioneer 84G62 truly led the way from yield potential. But they both had a bit of trouble with anthracnose.”
That isn't unusual in certain areas of the state, primarily where sorghum is planted behind sorghum. Poor drainage was also a factor in many of the fields with anthracnose.
“My reporting that doesn't mean you shouldn't plant those two hybrids. Just plant them in the proper places. They certainly have great yield potential.”
Can a fungicide be applied to sorghum? “This will be debated much more next year than it was in 2007. I know of at least a handful of producers that put a fungicide of some sort on their sorghum. Most reported positive experiences.”
This year, for the first time, Lanclos used Quadris at 6 ounces on sorghum. “We got between a half-bushel and 3-bushel response consistently over five hybrids in the core block. As of right now, only Quadris will be labeled for grain sorghum in 2008. I did check on Stratego and Headline and it doesn't appear those will be available.”
The 2007 stacked-corn core block test had three locations in south Louisiana, two locations in central Louisiana and six locations in north Louisiana.
The six stacked corn hybrids were: Pioneer 32B29, Croplan 851, Dekalb 69-71, Terral 25BR23, Terral 25BR41, and Croplan 818.
In south Louisiana, Terral 25BR23 led the way, followed by Pioneer 32B29. In central Louisiana the 32B29 did best, followed by Terral 25BR23. In north Louisiana, Pioneer 32B29 did best at a bit over 210 bushels per acre.
For the Roundup Ready hybrid test, “we had seven hybrids across the trials. There were five locations in south and central Louisiana and eight in north Louisiana. There were the expected, usual yield discrepancies between north and south Louisiana.”
In south Louisiana, Dekalb 63-62 won out at almost 190 bushels per acre. Pioneer 33M53 did best in central Louisiana. The Pioneer variety was just behind Dekalb 63-62 in north Louisiana. The rest of the varieties “were very strong contenders.”
The corn hybrid “best bet” list for 2008 includes: Croplan 851, Dekalb 63-62, Dekalb 69-71, Dyna-Gro 58P59, Dyna-Gro 58P60, Garst 8247, Garst 8295, NCT 6361, Pioneer 31G65, Pioneer 32B29, Pioneer 32B29, Pioneer 33M53, Pioneer 33R81, Terral 25R31, Terral 25BR23, and Terral 26BR41.
“It's clear on a statewide basis, there is a yield advantage by planting corn in early March. Looking at it regionally, north Louisiana has the highest yields when planting from March 15 to March 28. So you don't want to jump in too early.”
In central Louisiana, the highest yields are seen when planting is between March 1 and March 14. Yields drop significantly when planting later.
In south Louisiana, there is much more flexibility with the corn planting window.
As for fertilization, “I want to point to a test looking at timing. For the last three years here at (the Dean Lee Research Station), we've planted Terral 25BR23 and used 180 units of nitrogen. It was applied at different growth stages at the following plant heights (in inches): 3, 6, 9, 12, 15, 18 and 21-inch-tall corn.”
The objective was to find out how early is too early to apply nitrogen.
“Nowadays, as soon as the corn is 1.5 inches tall, there are knife rigs running. I was driving down the highway watching this wondering, ‘Is that too early? Will the nitrogen be available if the roots haven't established themselves?’”
Based on the data collected over the three-year test, “there are no statistical differences seen. The take-home message is that the 18-inch and 21-inch corn is a bit too large to apply the fertilizer. More than likely, what's happening is the roots are being pruned by the knife rig and that's causing a slight yield drag.”
Is it worth irrigating corn in Louisiana? “If you have access to irrigation, the answer is an emphatic yes. That advice comes after 75 on-farm trials from 2004 through 2007. We broke the numbers down further into planting dates from March 1 through March 20.
“Planting corn in the optimum window and irrigating it provide 10 to 12 bushels more than (dryland). Statewide, delaying planting to March 21 through April 5 really affects yields negatively.”
This year, there were four locations for Group 3 variety tests. Varieties tested were: Dyna-Gro 31J39, Delta Grow 3950, Terral 39RS31, Progeny 3900, and Deltapine 3861. The leaders over the four locations were Dyna-Gro 31J39 and Delta Grow 3950.
For Group 4s, south Louisiana had three locations, central Louisiana had two and north Louisiana had eight locations. The varieties tested in the core block were: DeltaKing 4968, Dyna-Gro 36Y48, DeltaKing 4866, Dekalb 4651, Terral 46R15, Deltapine 4546, Pioneer 94B73, Croplan 4444, Terral 48R14, and Dyna-Gro 3463.
“North and south Louisiana had good growing seasons. But central Louisiana was truly blessed this year. We never stressed for water and the beans did incredibly well.”
Group 5 variety tests were conducted in three locations in south Louisiana, two locations in the central area of the state and one location in the north. Ten varieties tested in the core block: DeltaKing 5161, Delta Grow 5555, Terral 55R15, Terral 59R16, Dyna-Gro 33B52, Delta Grow 5630, Croplan 5555, Deltapine 5634, Asgrow 5905 and Deltapine 5808.
In south Louisiana, the Group 5 leader was Terral 55R15 followed by Delta Grow 5555. In central Louisiana, Terral 59R16, DeltaKing 5161 and Delta Grow 5555 topped the test. In north Louisiana, there was a three-way tie at the top between DeltaKing 5161, Delta Grow 5555 and Terral 55R15.
In double-crop soybeans and wheat, how you handle the stubble is very important. “I definitely promote burning it off because I prefer a cleaner stale seedbed. However, if you want to leave stubble, research indicates the higher stubble benefits the soybeans.”
As for maturity groups to go with, most Louisiana wheat comes off between May 10 and May 20. “That's still a favorable planting time for soybeans. The best bet is to plant maturity groups between 4.7 and a 5.3.”