by AgFax Media LLC, AgFax.com
Corn harvest has widened in the lower South. At the least, more corn has reached black layer and crop advisors in a number of states are recommending that farmers curtail irrigation on substantial portions of the crop.
Soybean harvest in Louisiana's early-planted soybeans may begin over the next week if isolated cutting hasn't already started somewhere.
Worm pressure in soybeans varies, both by counts and species mix. Worm treatments are being made, mostly on a scattered basis. The assortment – depending on geography and other factors – includes bollworms, fall armyworms, loopers and green cloverworms.
Stink bugs are being sprayed on what sounds like a wider basis. Redbanded stink bugs continue to be the prime target in Louisiana. It has triggered treatments in Mississippi's south Delta, as reported earlier, and one of our contacts this week found what may be treatment levels of redbanded in southwest Arkansas.
Kudzu bugs are easy to find in parts of the South as we head into August. The insect was mostly a no-show in many areas during 2015, and entomologists had hoped that parasite activity and a fungus had reduced the insect's importance. But numbers have clearly built this year and treatments will be necessary in places.
Sugarcane aphids have built to treatment levels in more areas since last week's report.
LOUISIANA CROP REPORTS
Sebe Brown, Northeast Louisiana Region Extension Entomologist:
"Calls are slacking off about bollworms in soybeans. Guys got them under control, plus canopies are closing in more fields, so those beans are past the point of being attractive to bollworms.
"Stink bugs are still here and it's mainly redbanded now through the state. They have a way of colonizing fields and displacing other stink bugs. Treatments are going out all over the state, and guys with beans close to harvest are adding an insecticide for redbanded with their desiccant. At R6.5 redbanded still could cause quality issues. I'm also told that certain elevators classify stink bugs as foreign matter and will dock loads if too many are carried out of the field.
"A little soybean harvest may start next week in south Louisiana, if not the week after that. Corn harvest is underway in certain areas. No word on yields.
"Sugarcane aphids (SCA) are still on the radar in grain sorghum, but they're maybe not infesting fields as aggressively as in past years. That could be due to several factors – earlier planting, more acreage in resistant hybrids and growers being more proactive with insecticides. We still have a pretty decent headworm complex in grain sorghum.
"A reminder: our sweet potato field day will be August 31 at the LSU Sweet Potato Research Station at Chase."
Steve Schutz, Ind. Consultant, Coushatta, Louisiana:
"We're finding spider mites in about 400 acres of soybeans but really don't have anything that's legal to use that would work. I've contacted specialists and they said that bifenthrin could make the problem worse in the long run and suggested I wait for rain.
"Redbanded stink bugs aren't widespread in our area, but they are a big problem right now for some producers. Several fields have been sprayed 3 times. Where yield potential is low we're limiting treatments to every 10 days. I'll still check every 5 days. But if I find treatment levels on day 5 in low-potential fields, I'll check again in another 5 days and then decide whether a treatment is still needed.
"I found them on the Arkansas line a couple of weeks ago – literally. I parked my truck on State Line Road on the Louisiana side and found them in beans on the Arkansas side. We've since found them in some of our Arkansas soybeans and will likely spray.
"Bollworms have been an issue in soybeans here and there. Numbers have been really high in some R2 to R3 fields. We're maybe running into some pyrethroid resistance. A little frogeye leaf spot is apparent in some beans at R5 to R6, but I'm not inclined to treat. If we get a lot of rain, I'll rethink that.
"Nobody is cutting corn yet but we made our final round of irrigation last week."
Ashley Peters, Peters Crop Consulting, Crowville, Louisiana:
"We're still irrigating corn in late-planted locations or where we had to replant 3 times due to rain, flooding and cold conditions in the spring. Most of mine hit black layer last week and this week. A little harvest may have started this morning (7/26). A few growers in Franklin Parish are cutting samples, maybe where they planted corn in February and the stands survived.
"In soybeans we're dealing with corn earworms and fall armyworms in some fields. They've turned up in fields ranging from pre-bloom to R4. There's no pattern to where they've developed. I can find treatment levels in a field at R4 but not in an adjoining field that's also at R4. Moths are flying everywhere in cotton and beans, so I would think more worms are coming."