PRUNE AND RECYCLE: MECHANICAL HAZELNUT PRUNING AND ENERGETIC RECOVERY OF ITS BIOMASS

In order to expand the information on hazelnut mechanical pruning, but also to study the biomass produced by pruning as a source of energy, specific investigations were carried out in the period 2006-2007 in Piedmont on ‘Tonda Gentile delle Langhe’. In particular, four farms were chosen among those which best represent the local production, taking into consideration mainly the pedo-climatic environment and the age of the orchards. In each farm and year, non-pruned trees were compared to mechanical or manually pruned trees. Pruning cuts were performed in spring for two farms and after harvest for the remaining two farms. After two years of investigations, it was observed that manual pruning produces a higher quantity of biomass as compared to the mechanical method, although, for both pruning treatments, the dry weight biomass and its calorific power is not significantly different. A decrease in yield was noted for the pruned trees; but, for those mechanically pruned, yield reached a certain amount of nuts already in the season after the pruning operations. The better quality of hazelnut produced by pruned trees was also confirmed.