A website from UGA Cooperative Extension

My air conditioner is set at 78F and it is running at 4:00 AM.  You know what that means?  That means that in peanut fields across Georgia, white mold is out there chewing on vines and pegs and pods like at some buffet. With the humidity out there now it means that the leaf spot diseases are also out there somewhere happily producing more spores and more infection.  It means that sometime today those of you with peanuts in your counties are going to get on your list serve and say, “Bob may not know much about much of anything, but he is worried that diseases are about to take a toll on your peanut crop.  He thinks this because our weather (heat and humidity) is nearly perfect and if you get behind it is really hard to catch up.”

But wait!  There’s more for you to tell your growers…..  Picture 1 is from our buddy Eddie Beasley from Bayer CropScience- more tar spot on corn.  Yesterday in Terrell and today in Tift County.  Basically, later planted corn in SE and SW Districts will be affected by southern rust.  I am 100% sure.  I am also 99% sure that later planted corn in at least SW District will be affected by tar spot.  Got later planted corn?  Factor in at least one fungicide application (VT) for rust and tar spot.

But wait, there is even more good news- this time from Cole Moon in Bleckley County where he has found target spot on cotton AND our first report of areolate mildew.  (See pictures)  Target spot can be and IS a problem many times when it occurs early enough in the season (somewhere around the 3rd week of bloom).

AREOLATE MILDEW is ALWAYS are problem when it occurs in a cotton field in Georgia with more than a month to go prior to defoliation AND otherwise good yield potential.  You don’t have to believe me, why should you?  I believe in La Nina and El Nino and that a changing climate is going to mess up our crop production in GA.  But just ask Seth and Braxton and Taylor and Bill Rock Starr and BBT and Jeremy and Stephanie.  They will tell you that well-timed fungicide applications (Priaxor, Miravis Top, Headline, azoxystrobin) will make you yield and money.  I am not saying every cotton grower needs to spray for areolate mildew.  I am saying, based upon what Cole in Bleckley Co found yesterday, the areolate mildew genie is out of the bottle in Georgia and we need to be prepared.   

Update from the 25th

I have been pushing hard lately on the threat from white mold (aka stem blight, southern stem rot) because of the near-perfect conditions for the explosion of this disease with hot days and warm, muggy nights. Right now in T-town at 5 AM it is 73F and 97% humidity.  I can hear the white mold in the peanut field down the road near Dr. Harris’s house chewing on limbs, pods, and pegs right now.  Be prepared with solid fungicide programs; consult Peanutrx.org.

There is another risk.  As I have turned your focus to white mold (and southern corn rust and tar spot of corn and soybean rust), I do not want to distract you from peanut leaf spot diseases (early and late leaf spot diseases).  Until yesterday, I wasn’t that worried as I have not seen any this year.  That changed yesterday.  Our friends to the south in Jackson Co, FL, Ethan “BBE” Carter (BBT you should be proud…), Dr. Barry Tillman and Dr. Nickie Dufault shared with me pictures here of “early leaf spot gone wild” in a commercial peanut filed there.  The concern is that the grower has 30-40 days left before an ideal digging date.  The concern is that the grower seemed to use a good fungicide program, though I am not clear on the full program.  Bottom line, we DO NOT want this in Georgia.

These images are picture-proof that the leaf spot threat is real.  Advise your growers that as they fight white mold with Elatus and Excalia and Umbra and Convoy and Fontelis and Provost Silver and teb NOT TO FORGET the necessity to ensure protection from leaf spot at the same time, whether it is mixing something like Alto or Domark or Provysol or SPECIFIC sulfur or chlorothalonil with the white mold product (not always necessary…) or using products like Lucento and Priaxor and combination  of sulfur and Alto and Domark and chlorothalonil in bookend applications.  We are in the toughest disease period for white mold and leaf spot on peanut- late July through mid-September.  Don’t miss out.


Soybean growers are encouraged to mix some fungicide with their Dimilin and boron at the R3 growth stage.  We are not have many reports of soybean rust YET, but it wouldn’t hurt to take advantage of including a fungicide when you are already making a trip across the field.

Southern corn rust is a threat across SW and SE Districts.  Corn at or beyond hard dough is safe.  Late-planted corn will  be at great risk.

We continue to get new discoveries of tar spot on corn. 

We did find “grey leaf spot” on corn at the station which is highly unusual to find this far south in Georgia.  I have to believe that our cool spring and early summer helped this to happen.

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