THE INTERNATIONAL PLANTING SYSTEMS TRIAL AT EAST MALLING.

The trees at East Malling grew rapidly after planting and excessive vigour has been a problem on this trial, particularly with the trees on M.9. By the third year Golden Delicious/M.9 single row spindles at 2667 trees/ha had a leaf area index of 2 and were intercepting 60% diffuse light towards the end of the summer, while the full-field spindles on M.27 at 8889 trees/ha with a leaf area index of 2.5 were intercepting 72% light.
By the seventh year leaf areas had risen to 3 and 4 , with light interceptions of 74 and 91% respectively.
This latter value of 91% light interception is excessive and the trees of Golden Delicious on M.27 are showing very little growth in the shaded lower sections.

Yield build up was rapid with Golden Delicious where all systems gave over 60 t/ha in year four.
The cropping of the trees of Golden Delicious on M.27 has been very high with over 90 t/ha in some years, but bienniality has been a problem at East Malling with Golden Delicious.
The Gloster 69 trees, which were unfeathered at planting and at slightly wider spacings, showed a slower build up of yield but all systems with this cultivar were yielding over 47 t/ha by year five.

The ‘extra system’ at East Malling was a close planted single row spindle system on M.9 at the same tree density as the three-row North-Holland system.
These close planted trees have given very similar yields to the three-row system with both Golden Delicious and Gloster 69, indicating that the major difference between the three-row North-Holland spindle and the standard single-row spindle is the higher tree density rather than the pruning system.

IV International Symposium on Research and Development on Orchard and Plantation Systems

J.W. Palmer

https://doi.org/10.17660/ActaHortic.1989.243.33