Growth and Productivity of `Empire' Apple Trees following a Single Heading-back Pruning Treatment

Abstract

Dormant heading-back of terminal extension shoots on scaffold limbs on 2-year-old `Empire'/M.26 EMLA apple trees (Malus domestica Borkh.) in Apr. 1985 increased shoot growth from 1- and 2-year-old limb sections. Removing competing shoots to restore a single terminal extension shoot on each scaffold on half the trees in each pruning treatment in May 1985 had little influence on shoot growth. Annual trunk enlargement was reduced in 1985 and 1986 by heading-back pruning in 1985. Trunk cross-sectional area in Fall 1989 remained smaller for trees only headed back once, in 1985. Yields were decreased in 1986 through 1989 by heading-back treatments applied in 1985.