GDD base 50 = 380 at http://agebb.missouri.edu/weather/reports/gddTable.asp Phenology stages described according to the Modified E-L System http://door.uwex.edu/files/2010/10/ModifiedEichhornLorennzsystem.pdf We will make decisions on how to manage the canopy this week to manage the freeze and hail injury. … [Read more...] about Grape phenology and GDD accumulation