Flyspeck prevention, Full-dose Captan or Ziram: August-September spray dates

Background Information for this page
Return to Apple list for Easthampton MA
Weather data for Easthampton MA.  Forecast values begin September 24, 2017
      Continuous protection from roughly 14 days after Petal Fall (May 27) until 30 days before harvest preserves maximum lag between end of protection from the final fungicide application and potential for visible SBFS before harvest. 
      With continuous protection prior to the final fungicide spray, apples harvested by September 20 should be at low risk of visible sooty blotch and flyspeck (SBFS) if the Protection End Date from the final fungicide application is after August 15.  Apples harvested by October 10 (or by  October 31) should be at low risk if the Protection End Date is after September 3 (or September 12).
     These estimates are based on moderate infection pressure and climatic average temperature and rain/wetting hour accumulation.  Block history, local SBFS fungal density, tree size, cultivar, pruning, wind & sun exposure, air drainage, mowing and other site characteristics determine the actual risk of SBFS becoming visible before harvest.
Weather data for Easthampton MA.  Forecast values begin September 24, 2017
Inches Rain Spray Date
Estimates assume that fungicide was applied before rain on spray date
Protection End Date
for full-dose
Captan or Ziram
(deadline for postinfection strobilurin or Topsin M)
Date flyspeck infections could appear
(Left side = rough guess of flyspeck show date if weather beyond end of forecast range is in top 20% of years for both temperature and wet hours.  An "x" means there is no need for this scenario because show date is within forecast range.
    
Right side = rough guess of estimated flyspeck show date for small, open canopy, low-risk trees.)
0 Tue, August 1 Aug. 5  (Aug. 9) x September 9 (Sep. 26)
0.71 Wed, August 2 Aug. 5  (Aug. 9) x September 9 (Sep. 26)
0 Thu, August 3 Aug. 8  (Aug. 12) x September 13 (Sep. 29)
0.03 Fri, August 4 Aug. 8  (Aug. 12) x September 13 (Sep. 29)
1.32 Sat, August 5 Aug. 11  (Aug. 14) x September 15 (Oct. 6)
0 Sun, August 6 Aug. 20  (Aug. 28) x September 26 (Oct. 26)
0.10 Mon, August 7 Aug. 21  (Aug. 29) x September 26 (Oct. 29)
0.05 Tue, August 8 Aug. 22  (Aug. 30) x September 27 (> Oct. 31)
0 Wed, August 9 Aug. 23  (Sep. 2) x September 28  
0 Thu, August 10 Aug. 23  (Sep. 2) x September 28  
0.03 Fri, August 11 Aug. 23  (Sep. 2) x September 28  
0.34 Sat, August 12 Aug. 26  (Sep. 2) x September 30  
0.09 Sun, August 13 Aug. 27  (Sep. 2) x September 30  
0 Mon, August 14 Aug. 28  (Sep. 3) x October 1  
0.17 Tue, August 15 Aug. 29  (Sep. 3) x October 2  
0 Wed, August 16 Aug. 30  (Sep. 5) (Oct. 4) October 4  
0 Thu, August 17 Aug. 31  (Sep. 5) (Oct. 4) October 7  
0.31 Fri, August 18 Sep. 1  (Sep. 5) (Oct. 4) October 7  
0 Sat, August 19 Sep. 2  (Sep. 5) (Oct. 4) October 7  
0 Sun, August 20 Sep. 3  (Sep. 6) (Oct. 5) October 10  
0 Mon, August 21 Sep. 3  (Sep. 6) (Oct. 5) October 10  
0.36 Tue, August 22 Sep. 3  (Sep. 6) (Oct. 5) October 10  
0.21 Wed, August 23 Sep. 6  (Sep. 12) (Oct. 8) October 19  
0 Thu, August 24 Sep. 6  (Sep. 12) (Oct. 8) October 19  
0 Fri, August 25 Sep. 6  (Sep. 12) (Oct. 8) October 19  
0 Sat, August 26 Sep. 6  (Sep. 12) (Oct. 8) October 19  
0 Sun, August 27 Sep. 6  (Sep. 12) (Oct. 8) October 19  
0 Mon, August 28 Sep. 6  (Sep. 12) (Oct. 8) October 19  
0.02 Tue, August 29 Sep. 6  (Sep. 12) (Oct. 8) October 19  
0.02 Wed, August 30 Sep. 6  (Sep. 12) (Oct. 8) October 19  
0 Thu, August 31 Sep. 6  (Sep. 12) (Oct. 8) October 19  
0 Fri, September 1 Sep. 6  (Sep. 12) (Oct. 8) October 19  
0 Sat, September 2 Sep. 6  (Sep. 12) (Oct. 8) October 19  
1.03 Sun, September 3 Sep. 6  (Sep. 12) (Oct. 8) October 19  
0 Mon, September 4 Sep. 7  (Sep. 14) (Oct. 10) October 24  
0.11 Tue, September 5 Sep. 7  (Sep. 14) (Oct. 10) October 24  
0.96 Wed, September 6 Sep. 20 (Oct. 21) > Oct. 31  
0.47 Thu, September 7 Sep. 21 (Oct. 21)    
0 Fri, September 8 Sep. 22 (Oct. 21)    
0 Sat, September 9 Sep. 23 (Oct. 21)    
0 Sun, September 10 Sep. 24 (Oct. 21)    
0 Mon, September 11 Sep. 25   (Oct. 22)    
0 Tue, September 12 Sep. 26 (Oct. 24)    
0 Wed, September 13 Sep. 27 (Oct. 26)    
0.01 Thu, September 14 Sep. 28 (Oct. 29)    
0 Fri, September 15 Sep. 29 (> Oct. 31)