Response in terms of radical increment and stand cover in chestnut coppice subjected to different sylvicultural treatments

Manetti Maria Chiara 1, Pelleri Francesco 1, Becagli Claudia 1, Conedera Marco 2, Schleppi Patrick 3, Zingg Andreas 3

1 Centro di ricerca per la Selvicoltura (CRA), IT-52100 Arezzo, Italia
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

2nd European Conference on Chestnut, Debrecen, HU, 09-12/10/2013


Abstract

In this contribution we present the results related to a Swiss-Italian joint sylvicultural experiment consisting aiming at testing different treatments chestnut coppice stands for the production of high quality timber. To this purpose, we choose 5 young (7 to 17 years) and pure chestnut coppice stands growing on sites of medium to good fertility in central Italy and southern Switzerland, where we applied three different sylvicultural protocols: Single tree oriented sylviculture (option A) that is a early selection of 100-150 target trees per hectare to be isolated from competitors and pruned up to a height of about 5 m; Stand sylviculture (option B) that is medium to high intensity (50% of the shoots left) thinning mostly from below of each stool on the stand; No treatments (Option C, control). At present the different stands have been treated 1 to 2 times according to their development stage and post-treatment reaction patterns.
Suitability of the different treatments has been evaluated by the mean of different indicators both at individual and stand level. At individual level we yearly measured the radial increment of effectives (Option A) or theoretical (Options B and C) target trees as selected at time of first thinning. At stand level, we preceded at the yearly estimation of the crown cover by the measurement of the Leaf Area Index (LAI) Photosynthetic active Radiation (PAR) and the reduction in leaf biomass due to gall wasp attacks since its introduction.
Our results show a highly significant positive response in radial increment of the target individual of the single tree oriented sylviculture with respect to the ones of the stand sylviculture and the control, respectively. Crown cover has been rapidly reconstituted after the thinning in both sylvicultural treatments. In particular the single tree oriented sylviculture showed a very dynamic response despite the rapid succession of two treatments within few years. Due to the short time since the introduction of the gall wasp at the experimental sites, no clear impact patterns have been detected so far.