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  • Michigan State University Ag Bio Research
  • Project Greeen

East Lansing (MSUHort) Grape Leaf Black Rot Report (Report issued 8/23/2014 11:19 )

Wetting periods start with rainfall (at least 0.01 inch) and continue until the start of at least eight hours without moisture (rainfall, leaf wetness, high relative humidity). Wetting periods are classified as "ongoing" until eight consecutive dry hours have passed. After that, the official end of the wetting period is recorded (the start of the 8 hour dry period).

Black rot model available after 4/15. Pre-bloom estimated as 6/2/2014 (800 DD Base 42 after 1/1).
No missing degree day data.
Time period assessed for wetting events: 6/2 to 8/23/2014. Events between 8/9 and 8/23/2014 shown.
Missing hourly weather data: 8/23/2014 10-11AM (1 hour); Total of 1 missing hours
Wet Period Station Start of wetting period End of wetting period Duration (Hrs.) Avg temp (F) Rainfall (in.) Grape Leaf Black Rot Progress toward infection
1 East Lansing (MSUHort) 8/11 1-2PM 8/13 8-9AM Wet: 34
Span: 44
62.5 0.28 Yes 354%
2 East Lansing (MSUHort) 8/16 10-11PM 8/17 8-9AM Wet: 11
Span: 11
66.6 0.5 Yes 135%
3 East Lansing (MSUHort) 8/19 9-10AM 8/20 9-10AM Wet: 21
Span: 25
65.1 0.53 Yes 245%
4 East Lansing (MSUHort) 8/21 8-9PM 8/22 10-11AM Wet: 15
Span: 15
70.4 0.05 Yes 205%