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Here are the points I need you to know this morning:

  1.  We have NOT found southern corn rust in Georgia yet and I know of ONLY one field in Florida- Calhoun County south of Mariana.  There has GOT to be more, but we haven’t seen it.  Believe it or not, heavy rains and cooler temperatures actually work to our advantage as neither favors rapid spread of southern corn rust.  However, give me some hot and humid days and it will be “Katie bar the door…” for southern rust.  Should a grower apply a fungicide now?  Based upon growth stage he or she may be in a higher risk zone and consider a spray, but as we have NOT found southern rust yet, a spray is not as urgent as it might be, especially outside of extreme SW Georgia.  And if the fields are being scouted and rust is not found, that is also a reason to delay fungicide applications.
  2. We have NOT found soybean rust anywhere in the Southeast, to include Georgia, that I know of yet.  I am sure it is out there percolating somewhere.  But I do not know where.  At this point it is “watch and wait”.  But IF a grower is at R3 and IF he or she is putting out something like Dimilin, I would certainly tank mix a fungicide with it to take advantage of the trip.
  3. Peanut diseases:  Many growers have or should be starting fungicide programs for leaf spot control.  Conditions now are near-perfect for start of leaf spot epidemics.  rain splashed spores from the soil and debris to the leaves, initiating infection, as does the prolonged leaf wetness periods.  Also, fungicides may not have adequate time to dry between rains IF the grower can get back into the fields.  My suggestions are as follows:
    1. 25-30 days after planting and can get in the field?  Important now to put a fungicide out for most growers.  Given our conditions, though 1.5 pt/A of chlorothalonil is good, even better to mix some other fungicide with curative activity, examples include Alto and Dormark, to improve efficacy.
    2. Growers at this time can also use Aproach Prima and Absolute Maxx.  These are appropriate fungicides but I do not like to see either used under too much leaf spot pressure.
    3. Grower who are 40 days or beyond and needing to apply their FIRST fungicide:
      1. Leaf spot is the main threat now, though we are always aware of white mold.  Cooler temperatures and heavy rains have likely slowed development of white mold.
      2. Lucento and Priaxor are fungicides that come to mind in this situation- good leaf spot control and some white mold activity. They work well for applications in the 45-day after planting arena.
      3. Now would not be a good time for chlorothalonil alone.  I would proceed with extreme caution before using selections from “a” and “b” above.  In doing so. consider Peanut Rx.  If you are at “high” risk for leaf spot, do not do it.  If you are at “moderate” risk” for leaf spot, consider what could happen if you cannot make a timely fungicide application in 2 weeks.
      4. Application of Excalia + a leaf spot material or Elatus + a leaf spot material could go out at 45 days, however given our current conditions I would rather see you save these guns (as with our other strong white mold products) for 60 days after planting.
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