THE APPLE CURTAIN SYSTEM FOR MECHANISATION
The apple-curtain system with an over-row harvester is a possible way to increase the efficiency of handwork in apple growing without any loss of efficiency of investment and yield. It is being developed as a joint project between mechanical engineers and horticulturists.
The mechanisation of apple harvesting needs a simple, rational tree with flexible yield-bearing twigs and as few as possible rigid branches. The skeleton of the curtain is a central leader with one or two pairs of horizontal scaffolds at 180 cm or 140 cm and 220 cm. The cropping twigs hang vertically from the scaffold. In high-density plantings the horizontal scaffolds are not needed; the only important point is the vertically-hanging twig-curtain because the vibrating fingers of the harvester work horizontally. Flexibility is the other important requirement because both the vibrating fingers and the collecting devices go into the tree. The maximum height of the tree can be 3. 20 m. Jonathan or Golden Delicious trees are easy to train in this system because they have long, thin and prolific shoots. Starking is much more difficult because it has rigid and thick shoots but it may be made to fit the system by shoot bending. The first Hungarian apple-curtain plantings have about the same yield as hedgerow orchards of the same age and density but the size and colour of fruits are better because the curtain is thinner.
The capacity of the continuously working over-row harvester was about 25–30 t/h or 0. 50–1 ha/h, the efficiency of fruit detachment about 90% and the loss in collection about 30%. The quality of the collected fruits was excellent. During the next years we should like to decrease the loss in collection and develop the transport and handling systems while maintaining harvester capacity.