Late Season Rescue Thinning with Ethephon
Ethrel for Rescue Thinning in Eastern New York - Dan Donahue
Our colleagues in Massachusetts and New Jersey have conducted extensive research over the years on the use of Ethephon as a "rescue thinner" when fruits reach the 20-25 mm stage. I've posted a fact sheet and a power point presentation on the ENYCHP website that offers excellent guidance on the use of this material as a thinner. With this seasons bumper fruit set, coupled with weak thinner performance, ethephon should be considered as an option, but please follow the links below and study the information provided before acting. Ethephon can be a strong thinner, very sensitive to temperatures in the several days following application, capable of defruiting the tree in some circumstances. Thank you to Win and Wes for giving ENYCHP permission to post this information.
Rescue Thinning with Ethephon PowerPoint/pdf Talk (pdf; 4398KB)
- Author: Win Cowgill presented at the Connecticut Pomological Society
Fact sheet- F-129R UMASS-Rutgers- Late Season Rescue Thinning with Ethephon (pdf; 682KB)
- Authors: Wesley Autio, Win Cowgill

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