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  • Project Greeen

East Lansing (MSUHort) Grape Leaf Black Rot Report (Report issued 8/3/2015 0:31 )

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 5/31/2015 (800 DD Base 42 after 1/1).
No missing degree day data.
Time period assessed for wetting events: 5/31 to 8/3/2015.
Missing hourly weather data: 8/3/2015 Midnight-1AM - 8/3/2015 11PM - Midnight (24 hours); Total of 24 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) 7/27 Noon-1PM 7/28 7-8AM Wet: 13
Span: 20
67.7 0.06 Yes 164%
2 East Lansing (MSUHort) 8/2 10-11PM Ongoing. Last hour with moisture: 8/3 11PM - Midnight Wet: 2
Span: 2
63.5 0.68 None 22%