We are in peak planting season in Appling County. I have had several calls on preemergence herbicide options in cotton and peanuts the past week or so, see further in this email recommendations from UGA Weed Specialists in Cotton and Peanuts. We have also ran into some replant situations in peanuts due to the heavy amount of rainfall we experienced over the mothers day weekend a couple weeks back. I want to remind growers that UGA research has shown we can still obtain profitable yields with a 2.5 to 3 plants/foot stand and that it is recommended to replant peanuts if you have a stand count of less than 2.5 stand/foot or several 3 foot skips. Deciding whether to replant cotton can be much more difficult but with the economic outlook it would have to be a very terrible stand to convince me to replant a field, we achieve maximum yields with 1.5-1.75 plants/foot. Last Friday we planted the Appling/Bacon county cotton variety trial at Southeastern Gin. I would like to think Southeastern Gin for this collaboration with UGA to make this trial possible along with several other projects being conducted on their site. Also would like to think everyone that helped, James Clark, Wesley Griffis, Wade Parker, Savannah Beasley, and Zack Williams. If you are interested in any of the UGA research trials being conducted in the county give me a call and we can ride out to look at them together.
Topics Included in this Newsletter:
- Extension Precision Ag and Irrigation Blog – Dr. Wes Porter, UGA Precision Ag and Irrigation Specialist
- Peanut Weed Management Update – Dr. Eric Prostko, UGA Weed Specialist
- 2025 Cotton Weed Management Recommendations – Dr. Stanley Culpepper, UGA Weed Specialist
- Row Crop Disease Update – Dr. Bob Kemerait, UGA Plant Pathologist
- Lesser Cornstalk Borers in Georgia Peanut – Dr. Mark Abney, UGA Peanut Entomologist
- All About the Pod Podcast – UGA Peanut Team
- May Peanut Pointers – UGA Peanut Team
Extension Precision Ag and Irrigation Blog – Dr. Wes Porter, UGA Precision Ag and Irrigation Specialist
Safety Considerations When Working Around Pivots and Pumping Systems
This blog post covers safety when working around pivots. A very important topic, even though we’ve had rain and are into the crop production season this is a critical topic for many reasons.
Sprayer Calibration
There is a lot of spraying going on right now across the state and it’s a good reminder to ensure the sprayers are calibrated. The link to the new post can be found here:
Sprayer Calibration | Extension Precision Ag and Irrigation
Peanut Weed Management Update – Dr. Eric Prostko, UGA Weed Specialist
Dicamba Injury on Peanut
The “Program” Works
Here is a picture taken from my peanut plots earlier this morning. A friendly reminder that “The Program” really works (starting clean, twin rows, moisture activated residual herbicides) and has been for 28 years of peanut weed control research.
Check out this picture taken from my plots earlier today. A friendly reminder for peanut growers who need an early-postemergence treatment (aka “cracking” spray) in peanut. Program can be tweaked according to growers preferences/needs/experiences as follows:
1) Grower can replace Ultra Blazer + Basagran (aka “Georgia Storm”) with commercial Storm 4SL @ 16 oz/A. Storm is a pre-mix formulation of Blazer + Basagran.
2) If grower does not want to use any Ultra Blazer, can just use Basagran 4SL (8 oz/A) or Basagran 5SL (6.4 oz/A).
3) If grower does not want to use Dual Magnum, can use the following: Anthem Flex 4SE @ 3.0 oz/A; Enversa 3ME @ 48 oz/A; Outlook 6EC @ 16 oz/A; Warrant 3ME @ 48 oz/A; or Zidua 4.17SC @ 2.5 oz/A. Generally, I have no preference. When using either Dual Magnum or Outlook in this mix, additional NIS (1 qt/100 gals) is not needed.
2025 Cotton Weed Management Recommendations – Dr. Stanley Culpepper, UGA Weed Specialist
Row Crop Disease Update – Dr. Bob Kemerait, UGA Plant Pathologist
Southern Corn Rust Update
Thanks to a number of agents who have been sending samples of corn, kudzu, and soybeans to me in Tifton, based upon the samples, my students scouting, and scouting by consultants- no southern corn rust, tar spot, or soybean rust has been detected in Georgia or reported in the Southeast.
If history repeats itself, our first report of southern corn rust should occur in about two weeks by the end of the first week of June.
Several of you have called asking what corn growers should spray as they approach the tassel growth stage.
Here are my suggestions:
1. As no southern corn rust or tar spot has been found yet, growers could wait until disease is found. Of course there is risk we could miss early introductions of southern rust, but we are looking hard.
2. Growers, especially in extreme SW GA who want to play it “safe” could go ahead and spray at VT. If they did, risk is low enough that applications of tebuconazole, propiconazole, or pyraclostrobin are good; application of mixed mode of action products are better (broader spectrum and longer protective window).
3. I would hesitate to spend the money now on our “best” but also most expensive fungicides as I am not sure we should pull that trigger until we know disease has reached us..
Rhizoctonia solani of Cotton
In the pic below, there is a relatively healthy seedling along the bottom of the image with several blighted seedlings above. Note the girdling of the tender stem; this is caused by the fungal pathogen Rhizoctonia solani. Cooler weather with some rain has increased risk to seedling blight to cotton. Addition of azoxystrobin (6 fl oz/A) in-furrow can help to protect the seedlings. Noting can be done once the furrow is closed.
Northern Corn Leaf Spot of Corn
The leaves pictured below were found primarily on the older leaves in the canopy. Note the lesions were reddish brown with a hint of concentric rings. This is northern corn leaf SPOT (Bipolaris zeicola) and NOT southern corn leaf BLIGHT (Bipolaris maydis) and NOT northern corn leaf BLIGHT (Excerohilum turcicum). To the point: neither northern corn leaf SPOT or common corn rust are considered a threat to corn.
Fusarium wilt of cotton
Pics below are of wilted early-season cotton. Note the faded, blotchy leaf symptoms. Note the discoloration of the vascular tissue. This is Fusarium wilt on cotton; a disease that, in the southeast, always occurs in the presence of the Fusarium fungal pathogen and plant parasitic nematodes, most often sting or Southern root-knot nematodes. This disease can only be managed by fighting nematodes before the furrow is closed.
Seed rot and rhizoctonia of peanut
Pics below show severe stand loss in this field (note how wet it is) was likely from a combination of seed rot and Rhizoctonia. Wet soils increase risk to both. The grower is going to drop back in and plant more seed. I would a) hope to let the soil dry a bit and b) use azoxystrobin (6 fl oz/A) when I replanted to help against Rhizoc.
Bacterial Stalk Rot of Corn
Pictured below, individual corn plants dying in the field. Individual plants have a wet soft rot in the lower nodes with a strong stench. The field is being irrigated with pond water. This is “bacterial stalk rot” and when irrigation is from a pond, especially during dry weather, detritus including bacterial pathogens may get sucked up from the bottom of the pond and spread over The crop. Infection of some plants may occur, but the damage is usually not yield limiting.
Lesser Cornstalk Borers in Georgia Peanut – Dr. Mark Abney, UGA Peanut Entomologist
This week I received two reports of lesser cornstalk borer (LCB) in seedling peanuts. LCB infestations in peanut in May are not uncommon, but these reports underscore the importance of scouting fields on a regular basis.
What do you do if you find LCB in your peanuts? If the infestation is at or above the threshold, you should treat the field with an insecticide. There are currently two active ingredients that provide good efficacy against lesser cornstalk borer in peanut: chlorantraniliprole (Vantacor and others) and novaluron (Diamond).
“But Mark, my peanuts are only 28 days old. Surely I can wait awhile before I spray them.” Waiting to treat LCB is rolling the dice. It is possible that the environmental conditions that made your field favorable for an LCB infestation will change quickly and dramatically enough that treatment would not be profitable. If the infestation is barely at threshold and the extended forecast calls for cooler temperatures and significant rainfall over several days, I might be tempted to wait and see what happens before spraying my peanuts. Otherwise, my advice is to treat the pest. In my opinion, LCB is the insect that poses the greatest risk to most peanut growers in Georgia each year. Growers may be looking for ways to save money in 2025, but not treating LCB when thresholds are exceeded is not one of them.
There is no reason for a preventive treatment for lesser cornstalk borer; if the insect is not present in the field, do not treat. Moth traps provide some indication of LCB activity, but there is no treatment threshold based on moth trap capture. We have seen lots of moths in traps in Georgia peanut fields where larval infestations never developed. LCB moths in a trap are a signal to go scout the field if you are not already doing that on a weekly basis.
“My field is irrigated, so I don’t need to spray LCB, right?” Wrong. You cannot water LCB away with irrigation before the canopy closes in the row middles. Irrigated fields with a full canopy are rarely infested at threshold levels, but prior to that, fields are at risk.
If you have any questions about LCB management in peanut, please contact your local UGA County Extension agent.
The video below provides some tips for scouting early season LCB in peanut.
All About the Pod Podcast – UGA Peanut Team
EPISODE 12, Season 3 – Update on Seed Quality, Pest Management and Current Conditions
In this episode, Drs. Scott Monfort, Mark Abney, Albert Culbreath, Wes Porter, Bob Kemerait, and Eric Prostko discussed planting issues related to seed quality, herbicides, fungicides, insecticides, and the current conditions as of May 16th. If you have any questions or would like to suggest topics for discussion on a future episode, contact your local UGA Extension agent.
Go to All About the Pod News for supplemental information referred to during the podcast (Dicamba Injury) at: Season 3, Episode 12 | All About the Pod News
EPISODE 13, Season 3 – Current Crop Conditions Mid-May
https://open.spotify.com/episode/3H6HRaYErbEYoW5vwLEmTB?si=IrG5CZojRmC77kq7f4oSbg In this episode, Drs. Scott Monfort, Mark Abney, Albert Culbreath, Bob Kemerait, and Scott Tubbs discussed the current conditions as of May 23rd. We also got Agent Updates from Seth McAllister (Terrell), Wade Parker (East Georgia), Justin Odom (Seminole), and Justin Hand (Tift). If you have any questions or would like to suggest topics for discussion on a future episode, contact your local UGA Extension agent.
May Peanut Pointers – UGA Peanut Team