August 8, 2008
Early season corn harvest is underway across the southern US, with initial reports suggesting highly variable yields and grain quality, due to a general drought that affected most of the region.
Farmers in Texas - which produced more than 2 percent of the US corn crop last season - began bringing in their 2008 corn crop during late July and have already picked one fourth of all fields, which is well ahead of the normal seasonal harvest pace of 19 percent.
Unfortunately, much of that rapid progress may be attributable to poor yields in sections of the state affected by an undesirable mix of spring drought and summer storms.
Anecdotal reports of corn yielding no more than 20 bushels an acre has been turned in from fields near Sequin, which lies between Houston and San Antonio. The US Department of Agriculture said Texas cornfields produced average yields of 148 bushels per acre in 2007, and 296 million bushels of corn in total.
The past two weeks have been a microcosm of the growing season in Texas, with some farmers venturing out in scalding 100-degree-Fahrenheit temperatures to salvage drought-stressed corn as silage, even as Hurricane Dolly and Tropical Storm Edouard generated monsoon-quality rains that halted harvesting and destroyed unpicked corn in coastal sections of the state.
Weslaco extension agent Rod Santa Ana estimates that 30 percent of the local feed grain crop was probably "rendered worthless" by heavy rains and high winds from Hurricane Dolly. President George W. Bush declared 15 counties in South Texas as major disaster counties as a result of Dolly.
The moisture carried by Edouard and Dolly may also have a secondary impact on the Texas corn crop by increasing the incidence of aflatoxin, a known carcinogen produced by fungus that infects corn during times of drought, but requires damp conditions to flourish thereafter.
Some corn recently picked near Holland, Texas, reportedly contained aflatoxin contamination of more than 200 parts per million, which would make that grain unfit for consumption by humans, swine, breeding livestock and young animals.
Because corn carrying more than 300 parts per million of aflatoxin is legally banned and must be buried or burned, elevator managers report that some Texas farmers have already plowed under their corn crop, due to elevated aflatoxin levels.
Louisiana producers have already taken 12 percent of their corn crop to the bin, which is twice as much as normal for early August.
Growing conditions in Louisiana have essentially been the opposite of those seen in Texas, with plentiful early season rains followed by hot, dry weather.
"Timing in rainfall is everything to a farmer," said Louisiana State University AgCenter climatologist Jay Grymes. "Early-season rains are critical to produce a crop, but dry weather is needed to harvest it."
Louisiana produced more than 120 million bushels of corn in 2007, or about 1 percent of the total US crop.
"This is the type of year when farmers argue over who has the worst crop," said crop consultant Roger Carter of Agricultural Management Services in Clayton, La. "Drought and a 105 heat index are taking a toll on non-mature crops."
Carter said corn harvest began in his area of east central Louisiana during late July and has resulted in some surprising yields, despite the current drought.
"Corn harvest is progressing, with more farmers beginning," he wrote. "Reports are of no aflatoxin and 105 to 130 bushels per acre dryland yields. This is amazing considering the lack of rainfall. It was very droughty in the area where this corn was harvested, a sign that our corn yields could be a little better than we originally thought."
Combines have also entered cornfields in Alabama, Georgia, Mississippi and South Carolina, but had only picked 1 percent to 2 percent of the expected crop as of Monday, which was well shy of the five-year average of 2 percent to 9 percent.
Crop conditions are said to vary widely across the Southeast, and particularly in Alabama, where extension agronomist Dale Monks told the USDA that some corn stands in central and southern Alabama were the best he had seen in recent years, while other drought-stressed fields were bordering on crop failure.
Jackson County, Ala., extension agent Donald Mann said local corn yields were expected to range from near zero to 150 bushels per acre, with most falling between 60 and 80 bushels per acre.
Drought and insects have damaged numerous corn fields in Georgia this season.
"Corn yield will be down primarily due to stink bug and heat damage during pollination (and) silking," said one Georgia county agent contributing to a USDA crop condition report released Monday. "Corn yields will be down 10 percent to 15 percent due to high heat and drought."
Meanwhile, the USDA noted increasing reports of corn being cut for silage in South Carolina, because of a lack of grain potential.
"Corn has been a bust for most early-planted fields," a South Carolina extension agent told the agency. "The crop couldn't recover from the drought damage earlier. Harvest may begin this week in some Low Country counties with low expected yields."
In aggregate, Alabama, Georgia, Mississippi and South Carolina produced about 260 million bushels of corn in 2007, reporting average yields of 79 to 150 bushels per acre.
