Dr. Terence Robinson, Cornell-AgriTech, Geneva, New York

• For mildly biennial varieties, apply four sprays of Ethrel (1 pt/A) or NAA (4 oz/A) beginning when fruits are 25 mm in diameter and on a 10-day interval.
• For strongly biennialvarieties, apply four sprays of Ethrel or NAA (4 oz/A) beginning when fruits are 16 mm in diameter and on a 10-day interval. Apply the first spray of Ethrel at the low rate of 0.5 pt/A, followed by three sprays at the rate of 1 pt/A. Continue with two additional applications of NAA at 4 oz/A.
• Do not spray if temperatures will be over 80F on the day of spray or the following 2 days. Closely monitor the weather forecast using your preferred source.
• It is ok to mix with CaCl2 or other calcium formulations for bitter pit mitigation.
• All Honeycrisp and Fuji should receive these Ethephon sprays even those with a light crop. (The low dose and avoiding high temperatures will result in no thinning even on light cropping trees.)