Here is some information from Clemson peanut specialist Jay Chapin on the upcoming Field Day, Clemson’s new peanut specialist, and a quick update from the field.
Peanut Field Day
Please mark your calendar for the Annual Peanut Field Day at Edisto REC on 3 September (always the first Thursday in Sept.).
We will register starting at 9 am, go to the field by 10 am sharp, followed by a catered meal at noon.
Field plots will include:
New alternatives for thrips / virus control at planting
Growth regulator effect by variety
New harvest technology demonstration
Fungicide performance against leaf spot and white mold
New Peanut Specialist
For those who don’t get the opportunity beforehand, our Field Day will also be an excellent chance to meet and hear from our new Peanut Specialist, Dr. Dan Anco. Dan will be joining us sometime in August after wrapping up his work at the University of Florida and getting his family resettled here. He has a very strong background in Plant Pathology which is a big plus for the future of the S. C. Peanut Program. Come and help us welcome Dan to South Carolina.
The 100+ temperatures over the weekend caused mid-day wilting in some areas that had just gotten their first relief from previous drought stress. A chance of showers this week would be a big help in closing the canopy, suppressing insect problems, and keeping the crop fruiting. Overall we are in pretty fair shape for soil moisture, but it’s spotty, you don’t have to travel far to go from good soil moisture to drought stress.
Armyworms will probably be the topic of discussion this week as foliage injury is noticed in some fields. Almost everything I have seen is beet armyworm, which usually gets misidentified as fall armyworm in both peanut and soybean. The small beet armyworms look a lot like fall armyworm. Control wise, it doesn’t really matter with the diamide insecticides – Belt, Besige, Coragen, or, Prevathon.
Populations are very spotty with most fields having no problem at all. It’s a huge mistake to spray everything based on reports of defoliation in some fields. Closed canopy fields can readily withstand the 4 worm/ft threshold.
Focus on fields with smaller plants due to late planting or drought stress. These fields tend to have higher worm counts and can tolerate less feeding injury. That combination results in delayed canopy closure which can also affect weed control, particularly on runners. We have a few fields with 10+ worms per ft and small plants.
The tricky part is noticing the worms in time to avoid “spraying for revenge” after most of the feeding has occurred and the worms are ready to cycle out anyway. It’s also very frustrating to notice a worm issue a couple days after making a trip across the same field with fungicides.
Weed Wipers Under-Utilized
Escaped, “unkillable” herbicide-resistant pigweeds are a fact of life in many S. C. peanut fields. Sometimes there’s one here and there, and sometimes it’s a mess. The options are to pull them, keep twisting them up with 2,4-DB, or wipe them with 50% paraquat.
I think the third option is often overlooked. Years ago a Round-Up PVC rope-wiper was a common sight on the front of tractors in peanut fields. Newer applicators with pressurized wicks or wipers can be highly effective with paraquat. I have really been impressed with their ability to kill large pigweeds.
If no killable sized pigweeds (5-6” max. if we’re lucky) are present, instead of hitting the crop with repeated herbicide applications (Cobra, Blazer, 2,4-DB) to stunt escapes, it would be better to just wipe them once you get enough height differential. It’s cheaper, more effective, and easier on the crop as long as you avoid leaks.