Defoliaton will be challenge in this year's variable cotton

After two years of record and near-record yields, the 2006 Mid-South cotton crop is shaping up as a variable but average crop, thanks to a schizophrenic planting season and hot, dry weather during the growing season. The variability is going to create some challenges for defoliation and harvest.

On some fields, cotton producers are still pushing for a top crop. On others, they've pulled back and are looking forward to defoliation. In either case, a long harvest season appears in the offing.

“As late as some of the crop is, and as dry as some of the areas have been, if we get some late rains, we're going to have some juvenile growth and the crop is going to be much more difficult to defoliate than what we have experienced the last couple of years,” said Larry Steckel, weed scientist with the West Tennessee Experiment Station in Jackson, Tenn.

“I think we're going to have to be more aggressive. Probably in a lot of cases, to do a good job, we're going to need two shots of defoliant.”

Variability within west Tennessee cotton fields is more pronounced this year. “In areas that had a little deeper soils, cotton held on and has progressed a little more normally. But on sandy spots and bald knob hills, the cotton moved right along into cutout.”

The crops of 2004 and 2005 were much more uniform because so much of the cotton was planted within a short window. “This year, we have two distinct crops, one planted late April to early May. There's a gap, then a crop planted from mid-May to early June. About 80 percent of the crop is in that latter half.”

Defoliation in west Tennessee typically begins on early cotton in mid-September and gets rolling on later cotton by early October. But this year, the defoliation season will begin earlier on the early crop — late August in some places.

Steckel says in the event of late-season rains after cutout, “juvenile growth is the biggest concern I have. A lot of times, producers can get by with Prep and DEF, which has been the standard in Tennessee for quite a while. But we may need to add something to the tank to curtail some of that early growth. I think we'll see a lot more Dropp, or products that have a pre-mix of that in it.”

On later-planted cotton, Steckel says west Tennessee growers should consider a two-pass program. “Most growers don't want to plan for it, but end up doing it anyway. A Prep and DEF combination followed by Prep and Aim is a good two-pass program and you may want to add some Dropp to slow down the juvenile growth.”

Juvenile growth can also occur on fields that are not harvested in a timely manner. “That's a big thing to consider. We have a lot more cotton acres than we've had in the past. Our picker capacity is maxed out.”

The addition of a product like Aim or ET in the defoliation program addresses weed problems such as pigweeds and morningglories and is also a good option for producers in narrow-row cotton. “The research we've done here shows that one of the biggest problems in the 15-inch cotton is morningglories, which can get caught up in the spindles and cause problems, and late grass germination. Grass on the cut row in 15-inch cotton can be pulled into the spindle and jam the picker.”

Rainfall in west Tennessee has been spotty at best, according to Steckel. “We've been under severe drought stress from around Ripley south.”

Two other factors have complicated the growing season for cotton producers, according to Steckel. “A lot of cotton has received too much plant growth regulator. One reason is that the last two growing seasons, we've had taller cotton that grew quick. We didn't get that this year in the southern half of the state.

“We also have newer varieties out there. Before, when we were familiar with the varieties, we knew how much plant growth regulator to apply. We're now looking at the new Flex varieties and a lot of the new varieties that don't need to be as aggressively managed for growth as the older varieties.”

Despite the problems, USDA rated 76 percent of the Tennessee cotton crop in good to excellent condition. Arkansas and Missouri cotton crops are rated 65 percent and 64 percent in those categories, respectively. Meanwhile 61 percent of the Alabama cotton crop, 29 percent of the Mississippi crop and 15 percent of the Louisiana crop is rated in poor to very poor condition.

According to Mississippi Extension cotton specialist Tom Barber, hot, dry weather is to blame for much of it. “There are always hot spots in the fields and with this weather, it's made them worse. Even at layby, we were putting out some hot materials, and it's going to burn some leaves on those spots.”

The dry areas of field will open faster and be exposed to the elements for a longer period of time. “We have to manage for the average of the field. You have to manage for the good irrigated cotton.”

Barber says producers with irrigated cotton “are trying to push it hard, just to get it to put on a little more. Most of the cotton that was planted around April 1 is cutting out and it's been cut out for a week. A timely irrigation may push it a little bit to get the gravy crop in the top if we can. But with irrigation costs, I don't know economically how far we can push it.”

Barber is also starting to see some shed in some cotton “that is really loaded up in the top. This is the cotton that went through some hot temperatures. We're going to see some of that fall off a little bit.”

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