Селекційно-формова структура культурфітоценозів за участю Psevdotsuga Menziesii (Mirb.) Franko у Карпатському регіоні

The results of forest valuation and selection and form evaluation of the plantations of the most fast-growing introduced species are presented – for Douglas Fir (Green – Psevdotsuga Menziesii (Mirb.) Franko.), which not only passed the initial test, but adapted well in the Carpathian region and on adjacent areas for the past 160 years. For the first time in the region the relationship are sorted out between selection categories and mould signs of trees in the plantations of Douglas Fir for the development of direct and indirect phenotype criteria of the select biotypes – of selection base of plantation seed production of the of the same breed, installed the agronomic properties of plants of Douglas as the prototype of the select tree. For this purpose 10 permanent sample areas are laid in middle-aged, ripening, mature and over-mature in highly productive stands that grow in fresh and moist vegetation conditions at the height of 250 to 750 m A.S.L. Based on the research materials it is established that the Carpathian Douglas plantations are characterized by the highest productivity in Ukraine or with little admixture in its structure of European beech, or European silver fir, which do not compete with the main breed. Forest capacity of such mature plantations mainly differs from 1b to 1f and the storage of tree lengths on 1 ha and from 1100 to 2255 m3. In phytocoenosis where Douglas grows with the other forest species, especially with such competitors as Picea abies (the Norway spruce) and European larch, its forest capacity amounts to only I-II. In the various forest stands indicators of the selection structure are different. If the total number of select trees in the normal plantations does not exceed 20%, then in some select - it reaches to 33%. On average, it is found 14.8% select trees, of which 1.5% of the first category, and 13.3% - of the second category. Select trees of the first category are available only in those forest stands that referred to select. Almost half of all tree plantations form biotypes that are referred to the second class of growth by G. Kraft (48.1%). Trees of high selection categories, mainly are related to the first class of growth (over 85%), with a diameter exceeding the average indexes of the forest stands on 30-45% (the first category) and 25-30% (the second category), and in height on 10- 25 and 6-15% accordingly. Crowns of two types are typical for them - conical and wide conical. They also have brownish-grey colour. Barrels of the select trees of the second category are cleaned of knots on 24.2% of their height, and select trees of the first category - on 26.4%. The received results are aimed at improving the selection, seed production and preservation of the gene pool of Douglas Fir. The authenticity of results and conclusions are based on the long-lived experimental material that is collected in the significant amount that is statistically worked out using the many-sided methodological approaches.