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

Background Information for this page
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      Continuous protection from roughly 14 days after Petal Fall (May 31) 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 26.  Apples harvested by October 10 (or by  October 31) should be at low risk if the Protection End Date is after September 17 (or September 25).
     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 December 31, 2018
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 flyspeck show date for small, open canopy, low-risk trees.)
0 Sun, July 1 July 15  (Jul. 20) x August 5 (Aug 13)
0 Mon, July 2 July 16  (Jul. 21) x August 5 (Aug 14)
0 Tue, July 3 July 17  (Jul. 22) x August 6 (Aug 16)
0 Wed, July 4 July 17  (Jul. 22) x August 6 (Aug 16)
0 Thu, July 5 July 17  (Jul. 22) x August 6 (Aug 16)
0.20 Fri, July 6 July 17  (Jul. 22) x August 6 (Aug 16)
0 Sat, July 7 July 17  (Jul. 22) x August 6 (Aug 16)
0 Sun, July 8 July 17  (Jul. 22) x August 6 (Aug 16)
0 Mon, July 9 July 17  (Jul. 22) x August 6 (Aug 16)
0 Tue, July 10 July 17  (Jul. 22) x August 6 (Aug 16)
0 Wed, July 11 July 17  (Jul. 22) x August 6 (Aug 16)
0 Thu, July 12 July 17  (Jul. 22) x August 6 (Aug 16)
0 Fri, July 13 July 17  (Jul. 22) x August 6 (Aug 16)
0 Sat, July 14 July 17  (Jul. 22) x August 6 (Aug 16)
0.22 Sun, July 15 July 17  (Jul. 22) x August 6 (Aug 16)
0 Mon, July 16 July 17  (Jul. 22) x August 6 (Aug 16)
2.32 Tue, July 17 July 17  (Jul. 22) x August 6 (Aug 16)
0 Wed, July 18 July 23  (Jul. 25) x August 10 (Aug 21)
0 Thu, July 19 July 23  (Jul. 25) x August 10 (Aug 21)
0 Fri, July 20 July 23  (Jul. 25) x August 10 (Aug 21)
0 Sat, July 21 July 23  (Jul. 25) x August 10 (Aug 21)
0.97 Sun, July 22 July 23  (Jul. 25) x August 10 (Aug 21)
1.30 Mon, July 23 July 25  (Jul. 27) x August 12 (Aug 25)
0.18 Tue, July 24 July 26  (Jul. 29) x August 13 (Aug 27)
0.84 Wed, July 25 July 26  (Jul. 29) x August 13 (Aug 27)
1.00 Thu, July 26 August 1  (Aug. 3) x August 18 (Sep 7)
0.45 Fri, July 27 August 2  (Aug. 3) x August 21 (Sep 9)
0 Sat, July 28 August 3  (Aug. 5) x August 23 (Sep 10)
0 Sun, July 29 August 3  (Aug. 5) x August 23 (Sep 10)
0 Mon, July 30 August 3  (Aug. 5) x August 23 (Sep 10)
0 Tue, July 31 August 3  (Aug. 5) x August 23 (Sep 10)