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600 - 2016 Cercospora Leafspot (CLS) Control Recommendations

Cercospora Leafspot impedes sugarbeet growth, sugar accumulation and increases storage losses.  Managing to keep CLS infections at a minimum is crucial to all.  Information regarding CLS management is included in this issue of Ag Notes

Cercospora Leafspot Management Tips:

  1. Monitor Cercospora Leafspot DIV’s (Daily Infection Values) at: or the Crystal Agronomy App found at “the App Store” or “Google Play”
  2. Commence with spray program at first signs of CLS in field or in vicinity
  3. Pay attention to fungicide spray intervals…stretching these spray intervals equates to thin protection. Monitor Cercospora Daily Infections Values in-between applications to help in timing effective subsequent fungicide applications
  4. With early planting (April) we tend to see earlier (early to mid-July) CLS infection
  5. With tank-mixes, use full rates for each tank-mix partner
  6. Schedule application PHI’s (Preharvest Intervals) considering Pre Pile and Stock Piling dates (see chart included)
  7. TAP acres should be protected against Cercospora just as other acres. Unprotected canopies develop high quantities of Cercospora inoculum for next season for both you and your neighbors.

Fungicide Tank Mix Notes:

  1. Priaxor or Headline tank mixes with Tin’s…no concerns with either of these tank mixes. However, if using dry products always make sure those are in the solution first and fully dissolved. Otherwise with liquid Tin, be sure to put the Priaxor or Headline in the tank first and always start with at least a 1/2 tank full of water first - this is important with these SC formulations. Always put NIS in last if using it.
  2. Minerva Duo is a premix of TPTH and Triazole, simpler tank mix option vs. creating your own tank mix
  3. Do not add glyphosate as tank mix to Minerva Duo. For Minerva (formulation with just Triazole and not Tin) it is OK to tank mix with glyphosate and AMS.
  4. For Inspire XT, tank mixing is ok, knowing that Tins can be tough as you know for mixing. Make sure tank is half full and agitation is rolling. Dry Tin and Topsin are in the Wettable powders and water dispersible granules category. Follow WALES mixing order if dry Tin formulations are used.
  5. WALES Tank mixing order is as follows:
    1. Wettable powders and water dispersible granules
    2. Agitate tank mix thoroughly
    3. Liquid flowables and suspensions
    4. Emulsifiable concentrate formulations
    5. Surfactants/Solutions
  6. Proline and Tin, no observed tank mixing issues utilizing branded Tins and with no other products in the tank. If you are going to mix the two (Proline and Tin) to leave all other products out of the tank including the NIS that we like to see used with Proline. It is never a bad idea to do a quick jar test, especially if there are plans for anything else going into the tank.
  7. Tank mixing of Topsin + Tin + Glyphosate + Stinger is not recommended.

Cercospora Control Calendar

Mid to Late July (4 Spray Program)

  • Application 1 – TPTH* + Benzimidazole**
  • Application 2 - Triazole
  • Application 3 – TPTH*
  • Application 4 – Headline or Priaxor (apply Aug 25 through 1st week of September) 

Late July to Early August (3 Spray Program)

  • Application 1 – Triazole
  • Application 2 - TPTH* + Benzimidazole**
  • Application 3 – Headline + TPTH* or Priaxor + TPTH*  (apply Aug 25 through 1st week of September)

Early to Mid-August (2 Spray Program)

  • Application 1 – TPTH* + Triazole or TPTH* + Benzimidazole**
  • Application 2 – Headline + TPTH* or Priaxor + TPTH* (apply Aug 25 through 1st week of September )

Late August (1 Spray Program)

  • Headline + TPTH* or Priaxor + TPTH* (apply Aug 25 through 1st week of September ) or
  • Headline + Triazole or Priaxor + Triazole (apply Aug 25 through 1st week of September )

* TPTH should NOT be used more than twice per season

** Benzimidazole should be used only once per season and NEVER alone.

*** In tank mixing order, dry formulations go in first followed by liquids.

Fungicide Use Table

Crystal Agronomy App
As a reminder, for keeping a close eye on CLS development, the American Crystal Agronomy App is available and free, found at “the App Store” or “Google Play”. 

Grower Truck Driver Orientation & Review
Over the course of the past several years the ACSC Agriculture Department has developed training videos to help retain, train, and attract harvest employees.  We have developed videos such as Harvest Crew Orientation, Skidsteer Training, Piler Operator Training, and most recently a Truck Driver Orientation and Review video.  This newly added Truck Driver Orientation and Review video is intended to be used by ACSC Shareholders to aid in training new and returning truck drivers in preparation for sugarbeet harvest.  This video will be permanently located on under:  Sugarbeet Agronomy > Ag Tools > Grower Truck Driver Orientation and Review.  The Truck Driver video can also be found by doing a search on  We hope you will find this video useful and we encourage you to share this video with your harvest employees.  A SAFE highly efficient sugarbeet harvest will benefit everyone involved in the harvest!