Coming back here at the Forestry Research Centre in Arezzo, where I have been working for a long time earlier as a researcher and afterwards as director of the working group on “Forest biology and ...protection”, it is close to my heart clarifying two strictly related points. The first point concerns the story of this Centre. The second one The Italian Academy of Forest Sciences.Maybe not everyone knows the most important stages of the establishment and development of these institutions. I believe therefore useful to highlight briefly the main aspects.
Converting coppices into high forests with continuous cover has often been established during the last decades as a management goal in hilly and mountainous Mediterranean areas to attenuate the ...negative effects that frequent clearcutting may have on soil, landscape and biodiversity conservation. The silvicultural tool usually adopted for this purpose is the gradual thinning of sprouts during the long span of time required to complete the conversion, that also allows the owner to keep harvesting some wood. This research compared the effects of various thinning intensities (three treatments plus control) on the stand growth and structure of a beech coppice with standards. The optimal density after thinning was assessed by expressing mean tree spacing as a function of main stand attributes like stand height and stand dbh. This system was preferred to the empirical evaluation of the percentage of basal area to be removed in order to give forest managers general reference guidelines to adapt to the varying environments of the Mediterranean mountains. Results confirmed that the positive effects of thinning on mean stem volume is due more to the higher diameter increment than to different height growth. The acceleration of crown growth in the thinned plots allowed canopy closure to be achieved 13 years after thinning. This reduced the negative effects of the opening of the stand overlayer and the elimination of most suppressed trees on soil protection. Under the conditions examined, the best thinning intensity proved to be a stand density 20% lower than normal prescribed by the yield tables elaborated for beech high forests in Central and Southern Italy.
The paper describes the recruitment pattern, structure and yield of Calabrian pine (
Pinus nigra Arn. ssp.
laricio Poiret var.
Calabrica Delamare) stands on the Sila Plateau (Calabrian Region, Italy) ...that have been managed for over a century with a particular form of selection cutting. Management of these pine stands follows an unwritten plan which is based on a selection cut that is repeated approximately every 20 years on the same section of the forest. This type of management has preserved the typical forest landscape by maintaining a continuous forest cover.
Age, dbh, height, diameter increment and spatial distribution of the trees were measured in a stand where the owner had marked trees for cutting according to traditional criteria. Results show that stand structure consists of very small clusters (60–100
m
2) of trees in four distinct age classes which are the result of the natural regeneration occurring in the gaps opened by the periodic removal of the biggest trees in the stand. The volume of harvested trees is slightly less than the volume increment for the average cutting cycle.
The authors conclude that the description of truly traditional silvicultural systems, which have developed in different environments and with different techniques and often in contrast with established silvicultural methods, can make an important contribution to the search for ecologically, economically and socially sustainable ways of managing forests.
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