DIGITALNA ARHIVA ŠUMARSKOG LISTA
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ŠUMARSKI LIST 1-2/1966 str. 165 <-- 165 --> PDF |
by the Yugoslav Advisory Centre for Agriculture and Forestry, and the Republic Chambers of Economy. The mentioned Centre has already issued the first Yugoslav register of coniferous seed stands. a) Seed stands of coniferous species The selection of these stands is in the main finished. This work was first organized by the Institute for Forestry and Timber industry of the SR of Slovenia. The selection of these stands in the SR of Serbia, Bosnia and Hercegovina, and Macedonia was also carried out with the aid of forest institutes. In the SR of Croatia this was done by the Forest Seed Control Station, Rijeka, and in the SR of Montenegro by the Republic Centre for the Development of Agriculture and Forestry, Titograd. In the enclosed Table 1 is given a survey of coniferous seed stands. Their total reduced surface amounts to 7,136 ha., which surely does not mirror the actual needs and still less an optimum distribution of the particular species. The actual requirements and the progeny tests of individual stands will efect the necesary corrections into this register. The major part of these stands are State — owned. During the separation of seed stands it was endeavoured to choose pure stands, but this was not always possible. In the selected stands of Fir, Spruce and Aleppo Pine there occur 0.2—0.4 admixtures of other species. All these stands belong to the type of the »normal« seed stands. Almost all stands of the autochthonous species are of natural origin. Seed stands of the allochthonous species will contribute to the extension of the area of these species. b) Seed stands of broadleaved species Selection of these stands began two years ago, and in the individual Republics it is in progress or in its final stage. Of less interest is this selection to forestry practice because of fewer requirements of seeds of broadleaved species in this country. Also the research institutions could not devote themselves completely to this work because of other tasks. In the selection of these sands were engaged the forest institutes of the SR of Slovenia, Serbia, Macedonia, Bosnia and Hercegovina. The effect of the selection done so far can be seen in Table 2. If comparing the data in Tables 1 and 2 it is visible that the area of the thus far selected seed stands of broadleaved species is considerably smaller than the corresponding area of coniferous species, although the broadleaved species are considerably better represented in this country. In the previous work on the separation of seed stands the individual criteria of the selecionist were more expressed. In the further work efforts will be made to make them uniform. Taken as a whole this work has contributed that the previous collectiong seeds of forest trees in this country was replaced by an organized production of these seeds of high quality. This higher degree of production of forest seeds has been accepted as a transition to an up-to-date production of selected seed in seed orchards. The legal regulations soon to be issued should make it possible to implement this system in its entirety. In the individual Republics a division of districts with respect to the individual provenances has already been executed or is being prepared. Established were also modern organizations for the production of seed and planting stock. 2. Selection of plus trees Specialists from forest institutes and faculties have initiated the selection of plus trees in order to obtain the initial material for further work on the improvement of forest trees. The selection of plus trees on the basis of phenotype pointed at the complexity of this problem in consideration of the relative genotypic value of a phenotype, the objectives of selection (biological or technological characters, production of wood), and to the significance of the lower systematic units within the species for further work on its improvement. The forests of this country, taken as a whole, contain proportionally more »wild« elements than the forests of some other European country. The climatic, geological, |