UGA Extension Horticulturalist Dr. Lenny Wells says scab will likely start showing up on the developing foliage in another week or so with ongoing rain. Scab grows best on this rapidly expanding, tender leaf tissue. While we certainly don’t want to see another repeat of the scab issues we’ve seen in the last couple of years, this may provide an opportunity to sample orchards for fungicide sensitivity. Dr. Katherine Stevenson’s testing program, which began in 2014, has provided valuable information to help us better manage pecan scab. Last year’s results can be seen in Dr. Stevenson’s presentation here: 2015 GPGA Stevenson.
The program will continue during this growing season thanks to funding from the Georgia Agricultural Commodity Commission for Pecans. However, there are a few changes of which to take note. Samples may be submitted free of charge until July 31 (Last year’s experience showed the best results are obtained early in the season). There is also a limit this year of 5 samples per grower. Sampling instructions can be found here: Pecan Scab Fungicide Sensitivity Forms.
Below are clips from Dr. Stevenson’s power point summarizing last year’s sensitivities test: