Available Counties and Stations

For information on how to use the Grape Powdery Mildew Risk Assessment Index, see the Grape Pest Management Guideline. Risk assessement indexes are based on actual weather data for stations that take appropriate canopy readings.


Amador

Based on bud break, March 10, in Grenache may need to adjust for other cultivars that emerge earlier than the indicated date.

Risk index 20; Disease pressure Low; Pathogen status Normal

Calaveras

Based on bud break, March 17, in Grenache may need to adjust for other cultivars that emerge earlier than the indicated date.

Risk index 50; Disease pressure Moderate; Pathogen status Normal
Risk index 60; Disease pressure High; Pathogen status Normal

El Dorado

Based on bud break, March 19, in Grenache may need to adjust for other cultivars that emerge earlier than the indicated date.

Risk index 40; Disease pressure Moderate; Pathogen status Normal
Risk index 10; Disease pressure Low; Pathogen status Normal
Risk index 50; Disease pressure Moderate; Pathogen status Normal

Fresno

Based on bud break, March 9, in Thompson Seedless may need to adjust for other cultivars that emerge earlier than the indicated date.

Risk index 0; Disease pressure Low; Pathogen status Normal
Risk index 0; Disease pressure Low; Pathogen status Normal
Risk index 10; Disease pressure Low; Pathogen status Normal
Risk index 0; Disease pressure Low; Pathogen status Normal
Risk index 0; Disease pressure Low; Pathogen status Normal
Risk index 0; Disease pressure Low; Pathogen status Normal

Lake

Based on bud break, March 11, in Sauvignon Blanc may need to adjust for other cultivars that emerge earlier than the indicated date.

Risk index 0; Disease pressure Low; Pathogen status Normal
Risk index 20; Disease pressure Low; Pathogen status Normal
Risk index 0; Disease pressure Low; Pathogen status Normal
Risk index 0; Disease pressure Low; Pathogen status Normal

San Joaquin

Based on bud break, March 9, in Chardonnay may need to adjust for other cultivars that emerge earlier than the indicated date.

Risk index 10; Disease pressure Low; Pathogen status Normal
Risk index 10; Disease pressure Low; Pathogen status Normal
Risk index 0; Disease pressure Low; Pathogen status Normal
Risk index 60; Disease pressure High; Pathogen status Normal
Risk index 30; Disease pressure Moderate; Pathogen status Normal
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