Growth Analysis and the Comparison of Plantations of Different Tree Species in Zabreginj

1990

S. 281-287

2 Abb., 2 Tab., 10 Lit. Ang.

Unselbständiges Werk

200044676

In the past 30 years, indirect conversins were carried out in the area of about 150 ha in the region of Zabreginj and there will be more conversions performed in about 20 ha in the following decade. This represents more than one tenth of all the plantations in the Tolmin region. Due to the fact that they are classified among mature plantations in this region and that the first results can already be seen, the data offer represent an important experience in the development and tending of other plantations in the SGG Tolmin region as well as elsewhere in Slovenia. It was established that plantations of similar type might yield considerable growing stock as early as in the period of the young polewood although these are primarily wood assortments of inferior quality with exception of the sycomore and perhaps the European silver fir. At the moment, by far the best results as regards the quality can be established with the Norway spruce and the worst with the Sudeten larch. The latter in combination with the pioneer stage makes poor use of the production capacity of these natural sites, which are, however, of high quality. Other tree species make use of site capacities up to several times better than the autochtonous beech, naturally, at a given age and according to mass. Due to the fact that similar results of investigations are constantly going to gain in importance as regards the directing of increasing areas of artificial plantations at this stage of development, it would be wise to go on with such type of research work in the SGG Tolmin region. The influence of individual thinning methods on expenses and final yield, the varying of growing stock and increment throughout the production period and the time of culmination of the average age increment which determines the final cut will be of greatest interest for Slovene foresters in the future. Last but not least, forest economic aims in these areas in the future generations should become the object of more interest lest the high production capacities of these sites would not grow worse.