The more light all fruit trees in an orchard catch together, the higher the production in principle, or, it can be higher at any rate. Every fruit grower has grown up with this starting point. But what does this mean for the tree shape and in practice for the production?
During the Bundes Kernobstseminar, in early January this year in Bonn (Germany), two speakers, each in their own way, illustrated the influence of the tree shape on the production of pear trees.
Stefano Musacchi, professor at Washington State University (United States), compared in his presentation two planting densities with the accompanying tree shapes: an extensively planted system with spindle-shaped trees and an intensive growing system where the trees form a narrow hedge. A higher value of the proportion between the canopy surface area (L) and the tree volume (B) means that the leaves catch more light and that this makes a higher production possible.
Trial results confirm benefits of narrow fruit wall
The research results that director Jef Vercammen of Belgian pcfruit showed, confirm Musacchi’s mathematical approach. Over a period of 23 years, the research station in Sint-Truiden compared 7 different tree shapes of the Conference variety. The narrow hedge tree shape systems (Tiense hedge, ‘Kandelaar’ (candlestick), super spindle, Drapeau), on average produced 20% more than the spindle (see table 2). The production of the V-hedge – in fact two narrow hedges on one single stem – was even 30% higher than that of the spindle.
Read the article on this topic in the March issue of European Fruit Magazine