Crop load management of fruit trees is a challenge for producers. For this experiment apple, peach, and sweet cherry trees were thinned using mechanical blossom thinning (MBT), and hand blossom thinning (HBT) to mimic MBT. Apple bloom was reduced by MBT, but only one treatment consistently reduced fruit set. Marketable yield, fruit weight, and quality were unaffected by thinning treatments. An apple spur leaf study found that damage from MBT was negligible. Mechanical blossom thinning of peach significantly reduced fruit set and hand thinning requirements at ‘June drop’. Marketable yield, fruit firmness, and soluble solids concentration were largely unaffected by thinning treatments, but fruit weight and size increased in one year. The two highest rates of sweet cherry MBT and HBT reduced fruit set but total yield, fruit weight, and quality were unaffected. Overall, MBT may be a viable option for tree fruit producers, especially peach growers. / The University of Guelph/OMAFRA Sustainable Production Systems Research Programme, the Niagara Peninsula Fruit and Vegetable Growers' Association, NSERC.