Multi-leader trees and mechanical pruning in Europe

25 February 2015 | Ulf Kerer, AgFirst Nelson | Australian Fruitgrower / Future Orchards® article

Ulf Kerer reviews orchard systems and mechanisation developments being tested in northern Italy, with a focus on multi-leader trees, fruit-wall canopies and mechanical pruning. The objective is not mechanisation for its own sake, but simpler orchard structures that can maintain or increase yield and fruit quality while reducing labour requirements.

The article describes two-, four-, six- and eight-leader systems and notes that multi-leader trees can distribute fruit and light more evenly than conventional slender-spindle trees. Some trial rows were kept to about 2.6 metres high so work could be completed without ladders or platforms while still targeting commercial yields.

Kerer reports a multi-leader fruit wall yielding 87 tonnes per hectare in one example, with 1,700 trees per hectare averaging 53 kg per tree. He also discusses mechanical trimmers, fruit-wall “windows”, reduced row spacing and the need to continually assess cut quality when pruning mechanically.

The practical message is that orchard geometry, labour systems and machinery need to be designed together. Simplified canopies can make pruning, thinning and spraying easier to teach and execute, but they still require careful establishment, trellis support, light management and adaptation to local conditions.