AgFax Southern Grain
Insects Thriving, Rains Delay Corn Harvest
Owen Taylor, Editor 601-992-9488
Worms continue to build in places. Bollworms are the main player in soybeans, but soybean loopers have required treatments, as well. A mix of other worms and caterpillars are turning up, as well.
The redbanded stink bug (RBSB) has now expanded its range across Alabama’s southerly counties. Treatments also have been made in Arkansas and Mississippi, which aren’t normally in the insect’s range. For a clear idea about how destructive RBSB can be, see comments by Louisiana consultant Blaine Viator.
Bean leaf beetle numbers continue to pick up in some areas. In places, kudzu bugs are succumbing to a fungal infection.
Decidedly wetter weather has moved into parts of the South, delaying corn harvest and holding growers back from applying desiccants on early planted soybeans.
Correction: In last week’s web edition of AgFax Southern Grain I mistakenly quoted consultant Trent LaMastus as saying he was dealing with lespedeza worms in soybeans. That was a misunderstanding on my part due to a somewhat garbled telephone connection. I always try to set the record straight when this kind of thing happens. My apologies to Trent. – Owen Taylor, Editor
Curt Johnson, CRC Ag Consulting, LLC, Lake Village, Arkansas:
“Corn harvest has started. One client cut 60 acres, and estimated that it will average 225 bu/acre dry. That field was high enough to drain well during all of the early season rains. Most of his other fields stayed under water, especially on the bottom ends. I’ll be happy if we average 180 in that part of the crop. In soybeans, we treated redbanded stink bugs that topped threshold in some R5.9 to R6.1 soybeans. They were still there a week later but counts weren’t real high, and the beans were far enough along that I let them go.”
Wes Briggs, Briggs Crop Services, Inc., Bainbridge, Georgia:
“We’re well into corn harvest, and yields are mostly running 230 to 260 bu/acre. The lowest I’ve heard was 200, with the highest at 302. A fair amount of corn, though, is still in the field. We’ve had rainy weather for more than a week, starting last Monday (8/1). Last week some growers measured 5 inches and this week in spots another 5 to 8 inches accumulated. A little corn blew over in the area – thankfully, none of ours.
“We might desiccate some of our oldest soybeans in 2 weeks. We’re spraying younger beans for loopers and some beet armyworms. The MG4 soybeans look really good, and I’m excited about the yield potential.”
Gus Lorenz, Arkansas Extension IPM Specialist:
“A tremendous egg lay and larval hatch has been underway in cotton and soybeans. Plenty of bollworm moths are still flying around, too. Numbers are overwhelming in places. The last time we saw anything on this scale was in 2011. The flight has been happening on a wide basis. I’ve had calls from people in the Missouri Bootheel and Kansas who also are dealing with this.
“We’re catching 40 to 60 in 25 sweeps in places, with a lot of fields at one per sweep. By comparison, our variable threshold ranges from about 7 to 9 per 25 sweeps in these situations. As I noted last week, we’re finding infestations in fields that have already lapped, which is unusual. Don’t consider any beans safe, even where plants have reached R4 to R5. On top of that, we’ve got some mix of loopers, saltmarsh caterpillars and related pests. Worms have been getting worse for several weeks.
“Redbanded stink bugs have also made a big push into our southern tier of counties, and a lot of treatments have gone out. Bean leaf beetles are picking up extensively in places. We’ve heard reports of 2 per sweep with extensive defoliation in the tops of plants. In grain sorghum fields that are still in soft dough it’s not uncommon to find 2 to 3 worms per head.”
Dominic Reisig, NCSU Extension Specialist, Entomology, Plymouth, North Carolina:
“Soybean loopers are with us a little earlier than expected. I’m not hearing about anything worrisome yet, but be aware and scout. The big story is corn earworms in soybeans. Some fields are completely clean while others have pressure beyond belief, with 10 in 15 sweeps. The threshold varies, based on row width and the price of beans, but it tends to run 2 to 3 per 15 sweeps.
“Bean leaf beetles are around, and potato leaf hopper burn is evident in some varieties. Sugarcane aphid pressure seems higher in grain sorghum than last year, although they really haven’t blown up on any wide basis. People are pleased with control from Transform and Sivanto. I’m still getting questions about headworms in grain sorghum and also FAW and bollworms infesting whorls. It’s a wormy year.”
Sebe Brown, Northeast Louisiana Region Extension Entomologist:
“We’re kind of all over the place with weather. It rained 2 inches on Saturday at Winnsboro but only 0.2 of an inch at St. Joe. After tomorrow (8/10), the forecast calls for a solid chance for several days. Growers have been cutting corn as fast as they can. A few guys decided to hold off on desiccation shots on soybeans because they wouldn’t have time to harvest before the next rainy pattern sets in.
“A few soybean fields have been sprayed for loopers. I’m not hearing about any locations specifically at threshold yet, but if a big storm starts pushing air up from the gulf, soybean loopers could colonize pretty fast. Stink bugs persist, and redbanded have made a big push. Some growers have exhausted their seasonal use limit of acephate and bifenthrin. We’re scaring up a few corn earworm (CEW) moths in lush R1 to R3 plants that haven’t canopied yet.”
Angus Catchot, Mississippi Extension Entomologist:
“We’re about 2 weeks into this looper flight and some sprays are going out in soybeans. It’s not a terrible situation but we do have threshold levels in places. Late in last year’s crop we saw problems controlling soybean loopers with diamide materials, and some people are now finding loopers behind those treatments. These aren’t complete misses, but the loopers are obvious. It’s still early, and in a lot of seasons a part of our bean crop will still be vulnerable to loopers, even into early September. I’m thinking we’re on the front edge of loopers for 2016.
“On the whole, stink bugs are about as low as I’ve seen in a long time, but redbanded stink bugs are a factor. In scattered beans at R6 to R6.5 we’re finding 2X to 4X threshold. They probably will escalate. Our last big season with redbanded was 2009. As stink bugs go, redbanded are more aggressive than other species. If they turn up in a field, you may have to deal with them at least through R6.5 and even up to R7 if numbers are really high.”
Ron Smith, Alabama Extension Entomologist:
“Moth trap catches are up, and we’re seeing some combination of corn earworms (CEW) and tobacco budworms. Soybean looper moth counts are still very high, too, and they’re being reported in areas above Montgomery. In the last few days people have been seeing CEW eating blooms and foliage, mostly in doublecrop beans with open canopies.
“Several consultants reported velvetbean caterpillars (VBC) in soybeans in a few Tennessee Valley counties. This has been a very unusual pattern for VBC, which is a semi-tropical migratory species. We’re already finding it up to the Tennessee line, yet we haven’t detected significant numbers along the coast. Statewide, we’ve got a sub-threshold mix of about every species that affects soybeans – including fall armyworms and green cloverworms.
“Redbanded stink bugs have been confirmed across the state in our southernmost counties. That includes several counties where they’ve never been detected before. The fungus has caugyt up with kudzu bugs, and they’re dying off.”
Herbert Jones Jr., Ind. Consultant, Leland, Mississippi:
“Bean leaf beetles and threecornered alfalfa hoppers have increased in the last week in older beans, but numbers are still too low to consider treatments. The younger beans baffle me. I’ve steadily swept and used drop cloths but still can’t find worms.
“One grower applied a desiccant on about 30 acres of soybeans just to get the machinery running, but mine are mostly at R5 to R6. A sample of corn might have been cut this week in some of our crop, but it’s rained, so corn harvest has been pushed out a little. A lot of corn has been cut around Hollandale and Arcola, but no yield reports yet.”
George Hodge, Farmer, Hodge Farms, New Market, Alabama:
“We haven’t started harvesting corn yet. The crop really suffered during the dry, extremely hot conditions early in the summer. Potential yields in low spots look like they will be decent. Our soybeans look good right now. They were planted kind of late, right at the end of May, and they were stunted. But then we got a couple of inches of rain around July 4 and more after that. They are really blooming, and I’m hoping we get enough rain to put on pods and fill them out.”
Victor Roth, Roth Farm Service, Malden, Missouri:
“Our soybeans are mostly at R5, maybe up to R5.5 in places, so they’re not really attractive to bollworms at this point. We treated some fields last week for stink bugs and may spray one this week. So far, we’ve missed big worm issues that people are reporting elsewhere. We’ll keep checking, but a lot of beneficials are in the field working on the eggs. I’ve seen one or two corn fields where they’ve rolled up the pipe.”
David Hydrick, Hydrick’s Crop Consulting, Inc., Jonesboro, Arkansas:
“We’ve pretty much let all the corn go and I won’t be surprised if some isn’t cut next week. This is the earliest bean crop we’ve had in some time. Most fields range from late R5 to early R6, with a few at mid R6.
“We had a heck of a bollworm flight in places, with 200% worms in a few cases. We’re not treating everything, but over the last 2 weeks we have had to spray a lot of blooming beans at R2 to R3. We’ve also addressed a few stink bugs and loopers. Green cloverworms and velvetbean caterpillars have required applications in a few fields. In some of our river fields we sprayed bean leaf beetles where they were hitting 100% to 200%.
“Quite a bit of disease has been rumbling up in R5 to R6 beans. That includes frogeye, a lot of sudden death syndrome and a considerable amount of brown spot, plus soybean root disease. We’re finding aerial web blight, too. Pressure went up incrementally in early-crop beans during the last 3 weeks. Disease has run 50% to 60% in a limited number of fields. Those beans are about done, but disease will still hurt yields. Plenty of fields are totally clean, while others are simply bad.”
Michael Mulvaney, Cropping Systems Specialist, University of Florida, Western Panhandle:
“People are scrambling today (8/8) to get corn out of the field ahead of rains that are expected this week. At one point the moisture dropped to 22% in some corn, then it rained the next day. If moisture had dropped a few more points and the weather had remained dry, combines would have been running on a wide basis.”
Ty Edwards, Edwards Ag Consulting, LLC, Water Valley, Mississippi:
“We’ve hit black layer on most of the irrigated corn. I don’t know of anybody who expects to cut at high moisture and then dry it down. We’re 2 to 3 weeks from cutting a sample. Southern rust blew up a couple of weeks ago in about 200 acres of corn that had to be replanted, and we applied a fungicide.
“All of our soybeans have been sprayed with a fungicide, and a pyrethroid was included in places to take out kudzu bugs. Horrendous populations built in the hills. A lot of those fields hit or exceeded thresholds before it was time to apply a fungicide, so we let those ride. We haven’t sprayed any fields for bollworms or loopers, but that will probably change. Loopers are showing up now (8/8) at maybe 25% to 33% of a threshold. This seems a little early for loopers.”
Eddie McGriff, Regional Extension Agronomist, Centre, Alabama:
“We’re just now approaching black layer on our most mature irrigated corn, but it will still be a while before we start harvest. Some dryland corn was hit pretty hard by drought, and combines will be running in it first. Soybeans suffered some, too, but the overall crop actually survived the drought better than expected. I’ve found my first instance of frogeye this year. It was in a small field in the center of the state where it’s rained more. As you move east in my district the drought effects are more severe.”
Hank Jones, C&J Ag Consulting, Pioneer, Louisiana:
“It’s rained enough that we need a drier pattern so we can move into corn harvest and give beans a chance to dry down. Along the Interstate 20 corridor it rained 7 to 10 inches last week where storms were training through. At our farm in West Carroll Parish we’ve gotten close to 4.8 inches in the last 10 days. In Tensas Parish it’s ranged from 2 to 6 inches. We’ve been able to get in about a week’s worth of corn harvesting. Most guys cut a good bit of dryland corn. But once they got into the irrigated fields the moisture was high enough that they pulled back.
“Considering corn prices right now, nobody wants to cut wet corn and then dry it down. Dryland corn yields are up from last year – 140 to 160 bu/acre on the better dirt. Irrigated corn looks better than it did last year. I am hearing some yield variations by variety where northern corn leaf blight hammered corn in a couple of fields.
“The rain also held us up from applying Gramoxone on beans last week. This appears to be the best soybean crop I’ve ever checked. A lot of fields will average 70 bu/acre. Overall, this is the lowest amount of disease in soybeans that I can remember. Insect pressure has been normal. Last week I did pull the trigger on loopers across several thousand acres. The first 10 days of August tends to be our looper season.
“We have another chance for rain later this week, and the biggest headache is trying to time those expensive looper sprays. We need 3 to 4 hours for the material to get into the leaf. But with this weather pattern, we’ve flown on a treatment at noon with clear skies and then had a torrential rain pop up 2 hours later.”
Scott Stewart, Extension Entomologist, Jackson, Tennessee:
“We’re seeing a few loopers, and I’m getting calls about green cloverworms. We’re finding heavy numbers of bean leaf beetles in places, mainly in the earliest beans. In places, people are counting several hundred per 100 sweeps. When they get like this you can spray and then 2 weeks later find heavy numbers again. The threshold is 25% defoliation up to R6. But after that, 30% or even 35% will be okay.”
Harold Lambert, Independent Consultant, Innis, Louisiana:
“Corn harvest is going on, although rain has held some folks back. Rainfall has generally been spotty in the last 10 days – ranging from 1 to 3 inches. Sunday night (8/7) I think everybody in my area received an additional half-inch to 2.5 inches.
“Some of our early-planted MG4 soybeans have been harvested, and those fields will be planted in sugarcane. None of my other beans are ready for a harvest aid. We’re treating stink bugs, mainly redbanded, and they’re easy to find in many fields. Some of our later beans have a tall, dense canopy, and they’re hard to even walk through. So measuring stink bug infestations with a sweep net is difficult, at best.
“Soybean loopers have been around but are only a threat in isolated areas. Velvetbean caterpillars are more abundant than we’ve seen in a number of years. Some of this hot, hot weather has at least moderated their feeding rate. But as their development accelerates, I do expect that they will be hitting later beans with tender foliage.”
Zach Ingrum, Sanders, Inc., Athens, Alabama:
“Growers started shelling corn in drought-stressed fields planted in early March. It will be the last week of August before we see harvest running wide open in irrigated corn. We’re finding a few insects in soybeans, but beans have mostly been sprayed for one thing or another. We’re finding a good bit of frogeye in doublecrop beans and are making fungicide applications. Depending on the field, insects range from armyworms to podworms to bean leaf beetles, plus threecornered alfalfa hoppers and a few stink bugs.”
Blaine Viator, Certified Independent Agricultural Consultant, Plattenville, Louisiana:
“We had no winter down here, so we’ve been finding a lot of everything in soybeans. Plus, it’s rained and rained. Our average annual rainfall is about 65 inches, and we’re on track to exceed the average by quite a lot. The rain has disrupted everything – planting, fertilizer applications and treatments for pests and diseases.
“We’ve had an ongoing battle with insects. Redbanded stink bugs (RBSB) started out a little low, and we had other stink bugs in the picture before the redbanded finally displaced them. We’ll have to fight redbanded almost to harvest in a lot of the early-planted soybeans, the ones that we’ll follow with sugarcane. Depending on the area, we’ve treated redbanded 1 to 3 times, and in places we’ll likely make a fourth treatment before it’s over. All of those applications are based on economic RBSB thresholds, too.
“You’ve got to stay on top of redbanded. In one small field we picked up a threshold, but it was too wet that week for the grower to treat, and the field was in a location that couldn’t be sprayed by air. In the second week the farmer was really busy planting sugarcane and couldn’t stop to spray. In the third week when he finally was able to spray, a big thunderstorm developed.
“By the fourth week, the field was a loss – just bushes with nothing viable in the way of soybeans – and the farmer ended up shredding what was left. Fortunately, it was a very small field, but it does show what can happen. That was an extreme situation, of course, but in cases where people couldn’t make timely treatments we’ve occasionally seen 30% to 40% yield losses
“When RBSB hit hard, they also alter the plant’s physiology, so the plants won’t dry down, and harvest aids won’t solve the problem. Between the damaged beans and all the green stems going into the combine, no grain elevator will take them.
“In terms of worms, we’ve mostly been dealing with soybean and cabbage loopers. Treatments for redbanded would have taken care of nearly anything else out there. Because soybean loopers aren’t susceptible to materials we’d apply for redbanded, we’ve had to fall back on a larvicides for them.
“With all this wet weather, disease has been very pronounced. As is usually the case, we’re dealing with cercospora. Frogeye also has been extremely heavy in places. One grower applied a fungicide, not knowing he was having problems on part of the boom, so we ended up with an untreated check, you might say. The frogeye damage was unbelievable where no fungicide went out. Soybean rust isn’t much of an issue this year, probably because we’ve been covering everything with fungicides for other things.”