8/15/2023 0 Comments Douglas fir seedlings near me![]() ![]() ![]() At the beginning of the twentieth century, further imports of Douglas-fir seeds to Germany were less successful. In most European countries, the first Douglas-fir stands were characterized by excellent growth and health conditions. In Europe, the current distribution of the Douglas-fir is the result of a long introduction history, which started in 1826 (Köble and Seufert 2001). bud burst, bud set, growth performance, fall and spring frost hardiness) within the native distribution range (Gould et al. The complex glacial and postglacial history during the Quaternary period accompanied by the adaptation to very different ecological conditions led to specific patterns of genetic diversity and a large genetic variation in adaptive traits (e.g. In the contact zone of the two varieties, hybridization is evident (Gugger et al. The interior variety (also called Rocky Mountain variety) grows further east of British Columbia, across the Rocky Mountains to New Mexico (USA) (Eckenwalder 2009). The coastal variety grows along the Pacific coast and the west facing slopes of the Rocky Mountain range from British Columbia, Canada to California, USA. Within its native distribution range, in western North America, two distinct varieties of the Douglas-fir are known: the coastal variety ( P. The Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco) is the second most cultivated non-native conifer tree species in Europe after the Sitka spruce (Köble and Seufert 2001), which grows in more than 35 European countries. According to the genetic diversity indices, certified North American Douglas-fir seed sources should be preferred for planting in Central Europe. They show significant differences in the adaptive traits such as morphological characteristics and timing of bud burst. European seedlings have a lower genetic diversity versus the American seedlings and native populations. The results show that the investigated European seedlings originate from recommended American native seed sources and represent both varieties and inter-varietal admixed individuals. Adaptive traits of morphological characteristics and timing of bud burst of the seedlings are recorded and statistically analysed. Seedlings are genotyped for 13 nuclear SSRs and analysed together with reference data set and standard genetic structuring and assignment methods. We investigate 852 1-year-old seedlings from 10 different US and European seed lots representing 5 provenance regions which are sold in Germany and Austria. We compare the genetic diversity, morphological characteristics such as height ( h), root collar diameter (rcd) and the ratio of h/rcd, and the timing of bud burst. In this study, we investigate European seed lots for their native origin (variety and potential geographic origin in America) and assess the adaptability, growth and survival potential of European versus American Douglas-fir seed lots. Currently, seeds from both non-native European and native American seed stands are used for plantations. ![]() Due to its productivity and potential to adapt to the expected climate change, the Douglas-fir is one of the most important commercial non-native forest tree species in Europe. ![]()
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