Articles
CHEMICAL PRUNING AND PRUNING AIDS
Chemical control of shoot growth has been shown to be of great actual and potential value in this respect.
Application of a paint containing 1% NAA to cut surfaces after pruning prevented excessive re-growth at the top of the trees following severe pruning of vigorous spindlebush trees of Egremont Russet/MM.106. This technique is likely to be valuable not only in hedgerow orchards but also in multirow and bed systems where shoot growth above the cropping zone is undesirable.
In relation to new plantings, chemical control of shoot growth and branching in the early years has been found to have very beneficial effects.
Treatment with Off-Shoot-O, in the nursery and in the first two years in the orchard, gave more compact trees of Bramley/MM.111 than did conventional hand pruning.
The treated trees produced more, but shorter, shoots in the first and second years in the orchard and with the onset of cropping in the third and fourth years, these trees produced more flower clusters and a greater number and total weight of fruit than did the hand pruned controls.
Promising results are being obtained with chemical sprays to simulate the beneficial effects of hand tipping on fruit retention and fruit calcium concentration (hence storage potential) on cropping trees in the orchard.