Summary: The objectives of this project were: 1) Evaluate pre-bloom, bloom, and post-bloom chemical thinning agents and mechanical thinning technologies with particular focus on complete programs to achieve three goals: a) Minimize costs of green fruitlet thinning b) Maximize fruit quality c) Encourage annual bearing 2) Investigate influence of important variables (drying conditions, spray technology, carrier volume) on chemical thinner efficacy and fruit finish 3) Develop practical PGR programs to manipulate floral initiation and promote annual bearing 4) Evaluate horticultural effects of reflective materials (Extenday, mylar products) 5) Profile natural tree-to-tree variation in long-term cropping patterns in a newly planted apple block 6) Expand collaborative efforts with other research programs