Ag Fax: Midsouth Cotton
By Laykyn Rainbolt and Owen Taylor
AgFax
Cotton pests ramped up on a wider basis over the last week. Bollworms and plant bugs are the main players, but stink bugs are easing into the picture, too. Pressure from spider mites varies. Aphids are pretty much in the rearview mirror now, thanks to the fungus.
More of the early-planted cotton is hitting cutout.
Rains continue to stall applications and/or raise fears of washoff.
Soybean pests also are trending upwards. A few bollworm treatments have been going out, and stink bug applications are ongoing in parts of our coverage area. Loopers and green cloverworms have appeared earlier than usual, several of our contacts have noted, and scattered populations hit treatment levels.
Corn harvest has started a bit more in Louisiana.
Steve Schutz, Ind. Consultant, Coushatta, Louisiana
“It rained yet again over the weekend. I guess we’ve had wetter years, but 2020 has been incredibly wet. At my house, we’ve hit 53 inches so far this year. The historic average for that same period is 30 inches. I’ve had 2.5 inches in the last seven days and 8 inches in the last 30 days (from 7/27).
“The cotton really needs some hotter days. It was 69 degrees this morning, and the forecast shows low 70s and mid 80s for this week.
“Overall, cotton looks good right now, although we are seeing plenty of shed from weather and bugs. In places, we couldn’t apply insecticides in time due to rain, plus the rain washed off a number of treatments. Pix didn’t go out when needed in certain fields, again due to the rain, so we’re seeing shed because the cotton is growing like crazy.
“Overall, the cotton is 6 to 10 inches taller than I would like it to be, and canopies are pretty thick. All that said, the load still looks pretty good. Between 60% and 70% of the cotton responded pretty well to Pix.
“We do have cases where you can tell the results weren’t what we wanted. I was in a client’s cotton yesterday that is nearly six feet tall, although it does have fruit from top to bottom. Another client has vegetative growth like that, but the lower fruit load is lacking. The upper load – above the tenth or eleventh node – looks really good since we got the warmer weather a few weeks ago, but it is going to be a little behind the rest of the cotton.
“I did find a spot of target spot just starting in the southern part of my territory.
“Insect sprays are lighter this week than they were last week. Plant bugs are pretty consistent in the cotton. We don’t really have the big numbers like they typically deal with in northeast Louisiana, but plant bugs just won’t quit this year.
“We’re using a little acephate, and I’m using Diamond on 300 acres. This is the first time I’ve ever had a case where I thought Diamond would fit – a big load of juveniles but not many adults. The price for that material is more reasonable than it has been, so if it holds it for two weeks, it’ll be worth it. Otherwise, we’ll go back to acephate.
“We had a big egg lay about 10 days ago, and freshly hatched worms started showing up last week. Rains held people back from spraying when they wanted, so treatments probably went out a day or two later than needed.
“The egg lay is moving north because I found a bunch of eggs Friday around Gilliam that were hatching this morning, and we’ll do a shot up there soon. The highest count is maybe 10% to 12% fresh-hatched worms in pink blooms. So, numbers aren’t outrageous but are still above threshold. I also found some green stink bugs in cotton on Sunday morning.
“In places, we’re spraying redbanded stink bugs in soybeans. Most of the corn is at black layer, and the rest should be in 7-10 days.”
Ashley Peters, Peters Crop Consulting, Crowville, Louisiana
“Every other day it seems to rain somewhere, and more scattered showers fell yesterday (7/26), with rain expected into the week. Most of the crops don’t need rain at this point.
“Cotton looks pretty good overall. Our earliest planted cotton is somewhere around 2 to 3 NAWF and the majority of the rest is quickly approaching cutout. Over the last 10 to 12 days, we have sprayed all of our dual-gene cotton with a diamide for eggs or small larvae. We are monitoring the WideStrike 3 and Bollgard 3 but nothing has required a treatment so far.
“Plant bug pressure is normal. They are bad in the typical hot spots but more manageable in other areas, depending on location and surrounding fields.
“Aphids weren’t a huge issue this year. We controlled a few in conjunction with the first plant bug shot, but we really haven’t had to deal with them much past that. Knock on wood, we also haven’t had spider mite issues at all.
“We’re spraying some of the younger soybeans for bollworms, and we’re starting to treat more fields for redbanded stink bugs. Redbanded numbers aren’t terribly high, but we’re dealing with them as they show up. We did do a lot of fungicide applications last week in the beans.
“One of my clients has started cutting corn, and a few more farmers in the area are cutting, too.”
Sebe Brown, Louisiana Extension Field Crops Entomologist
“More people are seeing another heavy egg lay in the cotton, and our trap catches are spiking again. We expect to be in another moth flight this time of the year, and eggs aren’t hard to find in the cotton.
“I have heard of one case where the three-gene cotton technology failed to control bollworms. The dual-gene technology is clearly falling apart under the bollworm pressure.
“A lot of treatments are going out in the dual-gene cotton, while applications are situational in the three-gene fields. It really depends on how heavy the egg lay is and if damage is occurring. Diamides appear to be working very well for bollworm control.
“Spider mites were picking up, but we received some much-needed rain and the numbers have dwindled with the rainfall. But mites are still out there, so keep watching for them as everyone transitions to more broad-spectrum insecticides that can allow mites to build.
“Plant bug numbers are starting to decrease, but they are still present.
“Cotton is anywhere from 2 to 5 NAWF, and guys are starting to see the finish line for some of the April-planted cotton.
“Stink bugs are starting to pick up in cotton. We are at threshold in places for greens and browns, so be on the lookout. In drop-cloth sampling in certain spots, we are averaging one stink bug in every drop.
“Soybeans are mostly between R5 and R6 right now. Redbanded stink bugs (RBSB) are picking up across the state, which has been the trend the past few weeks. People in north Louisiana are consistently finding higher RBSB numbers, and a lot of applications are going out.
“In addition to RBSB, stink bug numbers are increasing in general, and the insects are starting to concentrate. Folks in the northern part of the state are beginning to fight stink bugs pretty hard.
“Velvetbean caterpillars have made a big entrance in north Louisiana, as well. If defoliation approaches 20%, especially after R1, folks are making applications. They don’t want to treat them, but some of the velvetbean populations are so bad that applications will be going out, regardless of stink bug numbers. Reports of soybean loopers are picking up, too, in the northern part of the state.”