Thema of the thesis is to analyse actual state and predict future application of english yew (Taxus baccata L.) in forest sites at chosen parts of PLA Moravský kras. Structure of parent stand and natural regeneration is analyzed on locations of interest Habrůvecká tůň, Lažánky, Sloup and Macocha. There was measured height, dbh, height of the crown, projection of the crown and space situations were drawned for mature individuals. In case of natural regeneration every individual was measured for height, distance from assumed parent tree, age and damage by game. At locations of interest were analysed 82 mature individuals. Height ranges from 1,7 to 13,4 m and dbh ranges from 4,1 to 33,7 cm. Natural regeneration containing 260 individuals was found near 35 mature yews and 58% was younger than 5 years. Damage by browsing was observed at 51 individuals, respectively 19,6 % of population. Mostly, trees older than 5 years are damaged. Damage is often repetitive. Only two individuals from natural regeneration are higher than 1m. From research is apparent negative influence of game on natural regeneration. Future of yew population in PLA Moravský Kras is conditioned to elimination of negative influence of game, which can be achieved by lowering numbers of game or suitable protection of trees.

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The strength of leaf fibers and the nutritional value of the edible fruit of several yucca species native to the U.S. southwest were studied to aid in the determination of species best suited for commercial cultivation by the Navajo Nation. The leaves were softened in an autoclave to facilitate the removal of the leaf matrix, conditioned in environmentally controlled chambers, and the fibers were broken using a texture analyzer. The fibers were frozen and cross sectioned and photographed to determine cross sectional area. Official methods were used to determine the nutritional content of the fruit. The mean tensile strength of Y. angustissima, Y. baccata, and Y. glauca was 484 ±79, 710±174, and 388±104 MPa, respectively. Fibers from the leaves of Y. baccata had a significantly higher tensile strength than the leaves of the other two species. Nutritional profiling of the fruit of Y. angustissima and Y. baccata indicated that the fruit of both species are good sources of vitamin C (73-119 mg/100g) and thiamin (0.20 to 0.22 mg/100g). Because of its edible fruit and superior leaf fiber tensile strength, Y. baccata is recommended as the best species for cultivation and commercialization.

Abstract I hela Europa har idegranen problem med återväxten. Olika återväxthämmande faktorer påverkar föryngringen i olika stadier, och det är aldrig bara en anledning till att föryngringen inte lyckas. Idegranen är skuggtålig men behöver ljus. Den gynnas av lövfällande bestånd då den drar nytta av vårens öppna krontak. I bristen på ljus stannar de yngre plantorna av i utvecklingen, dessa dör eller äts upp och föryngringen uteblir. Nästan alla naturligt förekommande äldre plantor (> 2 år) betas. Bete av idegran är idag ett stort problem för föryngringen då rådjurens matsmältning klarar av idegran. I Stockholms norra skärgård är det framför allt betet som hämmar plantornas utveckling. Idegranen har problem med sin återväxt och detta sägs vara ett karaktärsdrag för arten.