Conversion to high forest in ageing Turkey oak (Quercus cerris L.) coppices
Research, started in 1996, has been carried out in an aged coppice of turkish oak. Thesis considered were: natural evolution of coppice and thinning of different intensity, aimed to convert coppice into high forest. About 600-800 stems per hectare were released in plots where conversion was made. During silvicultural tending, in summer 1996, times of felling and successive operations were taken, including arrangement in bunches and yarding with PVC drag furrows. Data allow to define structure of stand before, immediately and six years after thinning. At a distance of six years thinning result successful and have determined a new structure of the stand, depressing the presence of dominated layer. In contro1 plots a reduction of number of stems and stumps way observed, whereas in plots where thinning was ere carried out, no damage or result of natural selection was observed. Plots where 600 stems per hectare were released exhibit an increment of 35 m 3 , v. 32 measured in plots with 800 stems per hectare.