ARS | Publication request: New strategies for thinning peaches

Submitted to: Compact Fruit Tree
Publication Type: Trade Journal
Publication Acceptance Date: August 1, 2008
Publication Date: September 1, 2008
Citation: Baughner, T.A., Schupp, J.R., Miller, S.S., Lesser, K.M., Reichard, K.H. New strategies for thinning peaches. Compact Fruit Tree. 41(2):8-9, 2008.

Technical Abstract: An evaluation of two mechanical thinners was conducted in four commercial peach orchard blocks in 2007. A mechanical blossom thinner designed by a German grower for thinning apple trees that employed nylon cords (strings) to remove blossoms was tested on peach trees trained to either a perpendicular-V or quad-V system. Thinning with the string thinner was conducted at 20 percent or 80 percent full bloom. A USDA spiked-drum shaker, originally designed for harvesting citrus, was included in the orchard tests at 45 days after full bloom. Mechanical thinners reduced fruit set, decreased follow-up hand thinning time, and increased the number of fruit in the 3-inch or greater size distribution in 100 percent of the trials. Net profits ranged from $116 to $1963 per hectare. String thinning at 20 percent bloom was similar to 80 percent bloom except the 20 percent bloom timing had a greater influence on fruit size distribution. Additional work is needed to optimize timing and crop load.