10mm diameter fruit. Photo: R. Crassweller, Penn State
The latest model run was completed at 9:30 AM this morning. In general the conditions for this week are not favorable for thinning, with highs predicted in the upper 50s to mid-60s. Three sites in PA had an hourly temperature below freezing which may result in some fruit damage. There is also a risk of cold damage for Tuesday morning. Cooler temperatures are not conducive to the use of 6-BA products. The preferred choice of a thinning material is carbaryl. The addition of an NAA product may help thinning in areas that might experience temperatures in the 70s. The predicted 4 day average balance suggests that chemical thinner rates should be increased as indicated by positive averages.