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Praca przedstawia historię, a przede wszystkim obecne formy ochrony jarzębu brekinii Sorbus torminalis w Polsce. Wskazano w niej przeszłe i obecne zagrożenia dla gatunku oraz przeanalizowano skuteczność dotychczas stosowanych form ochrony. Zwrócono uwagę na konieczność zmiany podejścia do ochrony tego gatunku w Polsce
The aim of this paper was inventory of the wild service tree (Sorbus torminalis), a very precious but, at the same time, one of the least known species of homeland wooded plants in the Taczanów Forest Inspectorate (Poznań Regional State Forest Directorate). The inventory was conducted from May 2010 to March 2011. The result of the inventory are 1127 specimens, of which 209 are strong mature trees and 918 are seedlings and young trees in good health. The field research shows that the wild service tree grows in the Taczanów Forest alongside its central and eastern part in 22 Forest Compartments, 8 of which are in the Koryta Forest District and 14 are in the Taczanów Forest District. The average height of mature trees (d1.3 > 10 cm) was 18.02 meters and the average breast height  dimension was 26.22 centimetres. The dominant forest type in this area which is acid oak forest from Quercetea roboli-petraeae class creates optimal conditions for the growth of the wild service tree. This is proved by an analysis of the species population dynamics which is characteristic for the species biology. The study shows that earlier inventories conducted in this region are incomplete and out-of-date, and this present inventory substantially broadens the knowledge about the wild service tree in the Taczanów Forest in the context of its local and national population.
This paper presents the results of the study on morphological variability of leaves of a scattered tree species Sorbus torminalis (L.) Crantz) in Poland. The leaves from short- and long shoots were collected from 17 localities widespread within the range of the species in Poland. Leaves were measured according to 15 morphological traits. The biometric data were subjected to multivariate statistical analysis in attempt to define variability between local populations. Most of the leaf traits are significantly correlated and are characterised by moderate level of variation. The average among population component of variation was 32.82% and 27.46% for leaves on short- and long shoots, respectively. The differences between sampled populations are significant, but only a weak geographical pattern of this differentiation was detected. Clinal type of variation was ascertained in two traits. Leaf traits which discriminate best the studied populations are also indicated. It was proved that leaves on short shoots differ markedly in shape and size from those of long shoots. Leaves on long shoots are steadier, but morphological trait values are less correlated. The study also confirmed the occurrence of individuals with leaves characteristic for S. torminalis var. perincisa Borbas et Feck and S. torminalis f. mollis Beck in a few Polish populations.
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The paper presents a brief history and present state of Sorbus torminalis in Polish forests. It shows the history of research and conservation of this species and changes in conservation strategies and methods. The future of the species, concerning both conservation and cultivation context looks optimistically.
In this paper the results of the 3-year observations (2001–2003) of seasonal rhythm of S. torminalis trees growing in Poznań in Dendrological Garden of Agricultural University and in forests of Wielkopolski National Park are presented. The observations included the course of leaf development, leaf coloration and leaf fall as well as flowering, fruit ripening and fall. Sixteen phenophases were taken into account. The differences in timing and duration of S. torminalis phenophases from year to year, between two sites and among trees within the same site are pointed out and discussed.
The paper presents the proposal of a strategy of conservation of genetic resources of wild service tree (Sorbus torminalis) in Polish forests. Some results of the recent studies on distribution, resources and genetic variability of wild service tree in Poland that make a scientific base of the programme are presented. Both in situ and ex situ methods should be applied in conservation of genetic resources of S. torminalis. Conservation affords should first to be focused on forest management oriented in favor of wild service tree (e.g. logging intervention, competition control, preparing of favorable sites for new establishments). Further, in situ measures should include selection of conservation areas (natural gene reserves) and preserving trees of the best quality (protected genotypes). These objects would provide seeds for new establishments and to feed populations of small size. The genotypes of the selected earlier preserving trees (about 250–300) would be protected in ex situ conservation objects – seedling and clonal seed orchards. These plantations would also provide seeds needed for future establishments. The genotypes of endangered populations or single trees of S. torminalis could be preserved in the Forest Gene Bank in Kostrzyca.
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