What is in this article?:
- Roundup Ready system
- Bt gene in cotton
- No-till the past eight season
“We’ve made three applications of Roundup this season,” Bill says. “After burndown, we usually add Roundup in our lay-by application of diuron in case any weeds have come through. As far as we know, we’ve had no resistant weeds.
“We’ve used Prowl and Prowl H20 since we’ve been no-till to control morningglory (our main weed pest), johnsongrass, and pigweed, and for other species where Roundup may be a bit weak. The Prowl is good insurance, it’s fairly cheap, and we hope the alternate chemistry will help hold off resistance.
“We’ve had a few small spots of marestail that regular rate Roundup didn’t kill. I don’t know if a heavier rate would’ve taken them out, but we just stopped and pulled them up as we were going through the fields.
“There has been some documented resistance in the area and before we start the season next year, we’ll discuss with our consultant and supplier about whether we should make changes in our weed control program — perhaps applying Prowl with our burndown, then coming back over the top with Dual. A big consideration there is the extra expense.”
The Cokers are believers in no-till, having first tried it back in the 1970s.
“The Soil Conservation Service was promoting no-till soybeans,” Larry recalls. “We Bush Hogged weeds, sprayed the fields, and planted. It was a huge mess, but it gave us an insight into the process and in the late 1980s we planted some no-till cotton as a trial. We made mistakes in procedures and timing, but we learned from our mistakes and the next year we expanded acreage. We closely followed all the no-till work being done at the Milan, Tenn., Experiment Station.
“To grow no-till cotton, we needed a good directed spray rig, which we didn’t have. We took an old cotton picker and put an oiling bar on the front for a directed spray. We could spray three different chemicals, and could spot spray for johnsongrass and cockleburs. Between us, we didn’t have enough hands to operate everything, but it still was a lot faster than hoeing or spraying by hand, and we used it until Roundup Ready came out.”
The Cokers usually hold off on planting until May. “We started May 12 this year,” Larry says. “We’ve found that May-planted cotton has produced our best crops; we’ve had trouble keeping stands when we planted in April.
“We soil test our fields every third year and follow the average recommendation. Most of the time, we spread 3-15-30 dry fertilizer at about 250 pounds per acre. Even where we have fairly good residual fertility, we’ll put out some fertilizer for maintenance. Then, we’ll apply 25 gallons per acre of 32 percent liquid nitrogen at squaring. On most of our sandy soils, if we get ‘normal’ rains, this gives us the capability of two bales per acre or more.
“We’ve sprayed a bit more than normal for plant bugs this year, but that pest is pretty much a given following boll weevil eradication. We added a pyrethroid for green stink bugs and any worms that might escape the Bt. In some areas, we had worms near the threshold level, but the Bt and pyrethroid took care of them. We’ve had armyworms in area hay fields, but so far they haven’t been a problem in our cotton.”