Cotton ginners, confronted with changing challenges in terms of the kind of cotton mills want and the kind of cotton farmers want to grow, often find themselves muttering about a Catch 22 dilemma.
“Foreign markets require a cleaner, longer fiber cotton, but when the ginner is ginning the cotton, he may not know where it's going to be sold,” says Stanley Anthony, research leader of the USDA's Agricultural Research Service Cotton Ginning Research Unit at Stoneville, Miss.
“If they gin for the foreign market, then it may be over-ginned for the domestic market, which could cost producers $5 to $20 per bale,” he told members of the Southern Cotton Ginners Association at their recent joint meeting with the Delta Council's Ginning and Cotton Quality Improvement Committee and Advisory Research Committee.
“We need to be able to gin smart, but the only way we can do this is if the buyer will tell the grower, ‘OK, this is the kind of cotton we want. If you can provide it, we'll take this percentage of your crop and guarantee you this price.’ The gin could then produce that quality of cotton — but only if the farmer had selected the correct varieties with the capability of producing that quality.”
Many varieties being grown today can't meet the stiffer quality requirements of foreign mills, Anthony said, “So if that's the market you're shooting for, you have to start off by growing the correct varieties.”
And if the raw seed cotton brought to the gin can't meet those requirements, “The ginner can only reduce the value of that cotton by trying to make it better than it is.”
For U.S. mills, typical requirements are for color 41, leaf 4, staple 34, and uniformity 81, while foreign buyers want color 31, leaf 3, staple 35, and uniformity 82.
In ginning cotton from variety studies at the Stoneville ginning lab, he said in 2002, 79 percent met the requirements for the U.S. market, “but 0 percent met requirements for the foreign market and couldn't have been sold overseas without a discount.” In 2003, 95 percent met U.S. requirements, 32 percent met foreign requirements.
“The primary reason was color. Unfortunately, the farmer doesn't have much control over Mother Nature, which has a significant impact on color. But most of the other fiber characteristics are under the grower's control — if he begins with the correct variety selections.”
Variety is also very important in the ginning process. “Variety is twice as important as the gin machinery that's processing the cotton. Differences in fiber quality across varieties are greater than differences due to ginning.”
Another variety-related issue that's “hot” in ginning circles is cottonseed and ginning charges.
Pounds of seed from many of today's widely-planted varieties are significantly below, on average, varieties of several years ago. Some varieties may produce less than 700 pounds of seed per 500 pounds of lint, while others produce a more-normal 800 pounds.
Lint or seed?
“But, the varieties that produce more seed may not produce as much lint,” Anthony says. “So, the question to the grower is, which do you want, lint or seed? Most producers will opt for more lint, which means we're going to have to figure out how to adjust ginning charges to insure that gins can earn the money they need to maintain and improve their facilities. If they're only getting 650 pounds, there could be a problem in not being able to offset the costs of ginning.”
Some varieties, he notes, don't withstand ginning as well as others. “Some of the newer varieties will need to be ginned differently, and that may require new technology that many gins don't have.”
Cleanability is another variety consideration, Anthony says. “Hairy leaf cottons usually require more cleaning than smooth leaf varieties. There are indications that hairy leaf varieties are making a comeback, so this may mean more cleaning and drying at the gin.
“Most new gins, and others that have been upgraded, were equipped on the basis of ginning primarily smooth leaf cottons, producing leaf grade 4. But if foreign markets now want leaf grade 2, many gins can't produce that without additional machinery or investment.”
A solution, Anthony says, may be to gin cotton sequentially, in blocks — all hairy leaf or all smooth leaf, so more aggressive cleaning and drying can be used on the hairy leaf cotton — or invest in new technology that will accomplish it automatically.
Farmers can help themselves, and ginners, too, by exercising greater care in covering and handling modules, he says.
Texas A&M studies
“Studies at Texas A&M show losses as high as $30 to $40 per bale from poor module covers. We've seen instances of growers using five-year-old covers that resulted in the loss of as much as 75 percent of the cotton in the module. Damp modules can increase ginning costs over $2 per bale due to the extra drying required.
“And when the gin ramps up the temperature, you're going to see changes in quality as it gets beyond 215 degrees; when it hits 350 or above, the changes are dramatic — fiber weight declines, short fiber content increases, uniformity goes down.”
Gins should control drying in order to produce lint at the gin stand with a moisture content of 5 percent to 7 percent, Anthony says. “Doing this correctly can mean 10 pounds to 20 pounds of cotton added to every bale. It also minimizes the need to add moisture to the bale.
“We also know we can add 5 pounds to 7 pounds of water back to a bale from humidified air after ginning without much of a problem. Direct water spray can add pounds, but it can also result in major damage.”
It's not unusual, he says, to find bales with 15 percent to 30 percent moisture content. “In a survey, we found that 26 percent of the bales examined were above the 7.5 percent moisture level recommended by the National Cotton Council.
“Once you get above that level, the grayness and yellowness of the cotton change dramatically. This change won't take place before the USDA classing at the gin, but it will change on the way to the mill — and when it gets to China, you may find that what left the United States as color 31 is now color 43.”