1 Italian Agricultural Research Council, Forestry Research Centre (CRA-SEL), IT-52100 Arezzo, Italy
2 Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), CH-6500 Bellinzona, Switzerland
3 Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), CH-8903 Birmensdorf, Switzerland
In this contribution we present the results of a Swiss-Italian joint sylvicultural experiment to verify if and how the single-tree-oriented silviculture can be applied to chestnut coppices to enhance timber production for industry and structural timber. The study was carried out in five 7 to 17 years old, pure chestnut coppice stands growing on sites of medium to good fertility in central Italy and southern Switzerland. The single-tree-oriented silviculture (option A, 100-150 target trees per hectare) was compared to the stand-oriented silviculture (option B) and to the natural evolution (option C) in terms of growth performance (i.e. individual annual radial increment), stand stability and efficiency (namely leaf area index [LAI], incidence of game and gall wasp attacks, harvesting damages). Suitability of the different treatments has been evaluated on effective (Option A) and theoretical (Options B and C) target trees as selected at time of the first thinning. First results show a significant higher increment response of the target trees in option A compared to the two other silvicultural systems, and a general fast and dynamic recovery of canopy cover after the thinnings in both silvicultural treatments, but even more in the single-tree-oriented silviculture, where two thinnings were necessary within few years. Due to the short time since the arrival of the gall wasp at the experimental sites, no clear impact patterns have been detected. Nevertheless, the attack severity seems to be higher in the target trees of the A option. Damages caused at the stem base by red deer or harvesting operations were clearly higher in the option A, which may reduce the positive outcome of this slvicultural option.
Keywords: Castanea sativa, sustainable management, stand silviculture, single-tree-oriented silviculture, thinning, long rotation system