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  3. Grape Powdery Mildew Risk Assessment Index
Weather, models & degree-days

RAI report for Collegeville (COL)

The grape powdery mildew risk assessment index (RAI) is useful for determining disease pressure and how often you need to spray to protect the vines. For information on how to use the RAI, see the pest management guideline.

Bud Break Date:

Grape Variety: Chardonnay

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Time Period: February 28, 2015 to September 29, 2015.

Because estimated data is included in the index, use reported RAI with caution. Interpret RAI using field surveys and your knowledge of the particular vineyard, along with additional weather data if you have it.

Date RAI Disease pressure Pathogen status Hours
70° ≤ Temp ≤ 85° 		Hours
Temp > 95° 		Notes
09/29/2015
20 low present 7.9 0.00
09/28/2015 0 low present 5.2 0.00
09/27/2015 0 low present 4.9 0.00
09/26/2015 10 low present 4.9 0.31
09/25/2015 20 low present 2.4 0.21
09/24/2015 30 moderate reproduces every 15 days 3.2 1.91
09/23/2015 40 moderate reproduces every 15 days 4.1 0.00
09/22/2015 50 moderate reproduces every 15 days 4.0 0.00
09/21/2015 60 high reproduces every 5 days 2.4 5.13
09/20/2015 70 high reproduces every 5 days 2.8 4.30
09/19/2015 80 high reproduces every 5 days 3.3 0.02
09/18/2015 90 high reproduces every 5 days 4.6 0.00
09/17/2015 100 high reproduces every 5 days 8.5 0.00
09/16/2015 90 high reproduces every 5 days 6.4 0.00
09/15/2015 70 high reproduces every 5 days 7.3 0.00
09/14/2015 50 moderate reproduces every 15 days 9.6 0.00
09/13/2015 30 moderate reproduces every 15 days 4.8 0.00
09/12/2015 40 moderate reproduces every 15 days 8.1 0.00
09/11/2015 20 low present 3.9 2.29
09/10/2015 30 moderate reproduces every 15 days 4.7 5.33
09/09/2015 40 moderate reproduces every 15 days 4.7 5.28
09/08/2015 50 moderate reproduces every 15 days 2.0 4.49
09/07/2015 60 high reproduces every 5 days 2.8 0.07
09/06/2015 70 high reproduces every 5 days 3.6 0.00
09/05/2015 80 high reproduces every 5 days 8.9 0.00
09/04/2015 60 high reproduces every 5 days 9.1 0.00
09/03/2015 40 moderate reproduces every 15 days 10.3 0.00
09/02/2015
20 low present 9.6 0.00
09/01/2015 0 low present 3.9 0.00
08/31/2015 0 low present 3.4 0.00
08/30/2015 0 low present 4.8 0.00
08/29/2015 0 low present 5.2 0.00
08/28/2015 0 low present 4.4 4.97
08/27/2015 0 low present 4.4 5.27
08/26/2015 0 low present 3.6 2.54
08/25/2015 0 low present 3.4 1.04
08/24/2015 0 low present 3.9 0.00
08/23/2015 0 low present 4.5 0.00
08/22/2015 0 low present 3.7 0.00
08/21/2015 0 low present 4.3 0.00
08/20/2015 0 low present 5.0 0.00
08/19/2015 0 low present 4.2 0.00
08/18/2015 0 low present 4.1 0.84
08/17/2015 0 low present 4.1 5.71
08/16/2015 0 low present 4.1 5.16
08/15/2015 0 low present 3.3 2.71
08/14/2015 0 low present 4.3 0.00
08/13/2015 0 low present 4.3 0.00
08/12/2015 0 low present 4.5 0.00
08/11/2015 0 low present 4.3 0.00
08/10/2015 0 low present 4.8 0.00
08/09/2015 0 low present 3.6 0.00
08/08/2015 10 low present 4.1 0.00
08/07/2015 20 low present 5.2 0.00
08/06/2015 30 moderate reproduces every 15 days 12.3 0.00
08/05/2015 10 low present 4.6 0.00
08/04/2015 20 low present 10.8 0.00
08/03/2015 0 low present 4.5 0.00
08/02/2015
0 low present 4.6 0.00
08/01/2015 0 low present 4.9 0.00
07/31/2015 0 low present 4.9 0.00
07/30/2015 0 low present 4.1 3.48
07/29/2015 0 low present 4.0 6.54
07/28/2015 0 low present 4.0 4.60
07/27/2015 0 low present 4.0 0.00
07/26/2015 0 low present 3.8 0.00
07/25/2015 0 low present 4.5 0.00
07/24/2015 0 low present 4.1 0.00
07/23/2015 0 low present 5.4 0.00
07/22/2015 0 low present 4.8 0.00
07/21/2015 0 low present 5.2 0.00
07/20/2015 0 low present 4.0 3.94
07/19/2015 0 low present 4.3 0.31
07/18/2015 0 low present 4.3 0.00
07/17/2015 0 low present 3.5 1.31
07/16/2015 0 low present 3.0 1.17
07/15/2015 10 low present 3.9 0.00
07/14/2015 20 low present 5.5 0.00
07/13/2015 30 moderate reproduces every 15 days 4.2 0.00
07/12/2015 40 moderate reproduces every 15 days 5.4 0.00
07/11/2015 50 moderate reproduces every 15 days 5.5 0.00
07/10/2015 60 high reproduces every 5 days 9.1 0.00
07/09/2015 40 moderate reproduces every 15 days 9.0 0.00
07/08/2015 20 low present 9.9 0.00
07/07/2015 0 low present 5.3 0.00
07/06/2015 0 low present 3.9 0.00
07/05/2015 0 low present 4.0 0.00
07/04/2015 0 low present 4.0 3.17
07/03/2015 10 low present 5.3 2.15
07/02/2015
20 low present 10.5 0.17
07/01/2015 0 low present 4.1 4.14
06/30/2015 0 low present 4.1 6.86
06/29/2015 0 low present 4.1 1.65
06/28/2015 0 low present 3.8 0.00
06/27/2015 0 low present 4.6 0.00
06/26/2015 0 low present 3.9 5.20
06/25/2015 0 low present 3.9 5.17
06/24/2015 0 low present 3.4 2.06
06/23/2015 0 low present 4.2 0.00
06/22/2015 0 low present 4.3 0.00
06/21/2015 0 low present 4.0 0.00
06/20/2015 0 low present 3.5 0.85
06/19/2015 10 low present 3.9 0.00
06/18/2015 20 low present 3.5 0.00
06/17/2015 30 moderate reproduces every 15 days 3.3 1.81
06/16/2015 40 moderate reproduces every 15 days 4.0 0.00
06/15/2015 50 moderate reproduces every 15 days 4.1 0.00
06/14/2015 60 high reproduces every 5 days 4.2 0.00
06/13/2015 70 high reproduces every 5 days 3.8 2.99
06/12/2015 80 high reproduces every 5 days 4.0 4.99
06/11/2015 90 high reproduces every 5 days 4.0 0.00
06/10/2015 100 high reproduces every 5 days 8.5 0.00
06/09/2015 80 high reproduces every 5 days 6.0 0.00
06/08/2015 60 high reproduces every 5 days 3.5 6.70
06/07/2015 70 high reproduces every 5 days 3.8 0.39
06/06/2015 80 high reproduces every 5 days 3.8 0.00
06/05/2015 90 high reproduces every 5 days 4.4 0.00
06/04/2015 100 high reproduces every 5 days 10.3 0.00
06/03/2015 100 high reproduces every 5 days 7.6 0.00
06/02/2015
100 high reproduces every 5 days 10.0 0.00
06/01/2015 100 high reproduces every 5 days 9.0 0.00
05/31/2015 100 high reproduces every 5 days 9.7 0.00
05/30/2015 80 high reproduces every 5 days 4.3 0.00
05/29/2015 90 high reproduces every 5 days 3.8 0.00
05/28/2015 100 high reproduces every 5 days 10.2 0.00
05/27/2015 100 high reproduces every 5 days 8.7 0.00
05/26/2015 100 high reproduces every 5 days 8.2 0.00
05/25/2015 100 high reproduces every 5 days 8.9 0.00
05/24/2015 100 high reproduces every 5 days 8.7 0.00 S1
05/23/2015 90 high reproduces every 5 days 6.0 0.00 P
05/22/2015 70 high reproduces every 5 days 6.0 0.00
05/21/2015 50 moderate reproduces every 15 days 4.2 0.00
05/20/2015 60 high reproduces every 5 days 5.6 0.00
05/19/2015 70 high reproduces every 5 days 6.4 0.00
05/18/2015 50 moderate reproduces every 15 days 4.6 0.00
05/17/2015 60 high reproduces every 5 days 1.7 0.00
05/16/2015 70 high reproduces every 5 days 6.6 0.00
05/15/2015 50 moderate reproduces every 15 days 4.2 0.00
05/14/2015 60 high reproduces every 5 days 0.1 0.00
05/13/2015 70 high reproduces every 5 days 1.7 0.00
05/12/2015 80 high reproduces every 5 days 3.7 0.00
05/11/2015 90 high reproduces every 5 days 5.8 0.00
05/10/2015 100 high reproduces every 5 days 8.2 0.00
05/09/2015 100 high reproduces every 5 days 7.5 0.00
05/08/2015 80 high reproduces every 5 days 4.3 0.00
05/07/2015 90 high reproduces every 5 days 0.0 0.00
05/06/2015 100 high reproduces every 5 days 6.6 0.00
05/05/2015 100 high reproduces every 5 days 6.6 0.00
05/04/2015 90 high reproduces every 5 days 7.2 0.00
05/03/2015 70 high reproduces every 5 days 8.9 0.00
05/02/2015
50 moderate reproduces every 15 days 3.8 0.00
05/01/2015 60 high reproduces every 5 days 2.6 0.00
04/30/2015 70 high reproduces every 5 days 4.3 0.00
04/29/2015 80 high reproduces every 5 days 5.7 0.00
04/28/2015 90 high reproduces every 5 days 4.8 0.00
04/27/2015 100 high reproduces every 5 days 9.9 0.00
04/26/2015 100 high reproduces every 5 days 7.4 0.00
04/25/2015 80 high reproduces every 5 days 0.2 0.00
04/24/2015 90 high reproduces every 5 days 4.5 0.00
04/23/2015 100 high reproduces every 5 days 7.9 0.00
04/22/2015 100 high reproduces every 5 days 7.2 0.00
04/21/2015 100 high reproduces every 5 days 6.6 0.00
04/20/2015 90 high reproduces every 5 days 8.5 0.00
04/19/2015 70 high reproduces every 5 days 5.1 0.00
04/18/2015 80 high reproduces every 5 days 4.4 0.00
04/17/2015 90 high reproduces every 5 days 4.8 0.00
04/16/2015 100 high reproduces every 5 days 9.1 0.00
04/15/2015 100 high reproduces every 5 days 6.9 0.00
04/14/2015 90 high reproduces every 5 days 0.0 0.00
04/13/2015 100 high reproduces every 5 days 8.6 0.00
04/12/2015 100 high reproduces every 5 days 8.7 0.00
04/11/2015 80 high reproduces every 5 days 8.6 0.00
04/10/2015 60 high reproduces every 5 days 7.0 0.00
04/09/2015 40 moderate reproduces every 15 days 4.0 0.00
04/08/2015 50 moderate reproduces every 15 days 0.0 0.00
04/07/2015 60 high reproduces every 5 days 0.0 0.00
04/06/2015 70 high reproduces every 5 days 0.0 0.00
04/05/2015 80 high reproduces every 5 days 0.0 0.00
04/04/2015 90 high reproduces every 5 days 5.3 0.00
04/03/2015 100 high reproduces every 5 days 7.0 0.00
04/02/2015
80 high reproduces every 5 days 6.4 0.00
04/01/2015 60 high reproduces every 5 days 2.6 0.00
03/31/2015 70 high reproduces every 5 days 6.5 0.00
03/30/2015 50 moderate reproduces every 15 days 4.5 0.00
03/29/2015 60 high reproduces every 5 days 4.4 0.00
03/28/2015 70 high reproduces every 5 days 4.8 0.00
03/27/2015 80 high reproduces every 5 days 3.9 0.00
03/26/2015 90 high reproduces every 5 days 5.8 0.00
03/25/2015 100 high reproduces every 5 days 7.0 0.00
03/24/2015 80 high reproduces every 5 days 2.3 0.00
03/23/2015 90 high reproduces every 5 days 1.7 0.00
03/22/2015 100 high reproduces every 5 days 6.3 0.00
03/21/2015 100 high reproduces every 5 days 8.2 0.00
03/20/2015 100 high reproduces every 5 days 6.8 0.00
03/19/2015 100 high reproduces every 5 days 8.2 0.00
03/18/2015 100 high reproduces every 5 days 7.3 0.00
03/17/2015 100 high reproduces every 5 days 6.9 0.00
03/16/2015 90 high reproduces every 5 days 5.2 0.00
03/15/2015 100 high reproduces every 5 days 9.0 0.00
03/14/2015 90 high reproduces every 5 days 5.2 0.00
03/13/2015 100 high reproduces every 5 days 9.5 0.00
03/12/2015 100 high reproduces every 5 days 6.2 0.00
03/11/2015 90 high reproduces every 5 days 2.5 0.00
03/10/2015 100 high reproduces every 5 days 6.4 0.00 P
03/09/2015 80 high reproduces every 5 days 6.4 0.00
03/08/2015 60 high reproduces every 5 days 6.0 0.00
03/07/2015 40 N/A Not Present 6.1 0.00
03/06/2015 20 N/A Not Present 6.4 0.00
03/05/2015 0 N/A Not Present 5.3 0.00
03/04/2015 0 N/A Not Present 2.6 0.00
03/03/2015 0 N/A Not Present 0.0 0.00
03/02/2015
0 N/A Not Present 0.0 0.00
03/01/2015 0 N/A Not Present 0.0 0.00
02/28/2015 0 N/A Not Present 0.0 0.00

P = missing data substituted with values from previous day
S1 = missing data substituted with values from Live Oak (LIV)