|Baugher, T. auxt|
Submitted to: Acta Horticulture Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 12/27/2007
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: Horticultural and economic evaluations of mechanical peach thinner prototypes were conducted in 2007 in four commercial orchard blocks trained to either a perpendicular V or quad V system. A string thinner designed by a German grower for thinning apple trees in organic orchards was tested at 20 or 80 percent full bloom. A USDA spiked-drum shaker, originally designed for harvesting citrus, was tested at 45 days after full bloom. Mechanical thinners reduced crop load by an average of 36 percent, decreased follow-up hand thinning time by 20 to 42 percent, and increased fruit in higher market value size distributions by 35 percent. Net profits ranged from $175 to $1966 per hectare ($71 to $796 per acre). Mechanical thinning at 20 percent full bloom resulted in more fruit in the 2 ¾ inch or greater size distribution than thinning at 80 percent full bloom. Detailed counts of flowers on branches with different orientations indicated that pruning may be adjusted to improve thinner performance.