Erfahrungen mit Provenienzen und Hybriden verschiedener Birkenarten

1991

7 Lit. Ang.

Unselbständiges Werk

6293

200054918

Results after 10, respectively 11 years of observation in 2 trial series with provenances, hybrids, open pollinations and material from seed orchards of Betula alleghaniensis, B. papyrifera, B. ermanii, B. pendula and B. pubescens are presented. The yellow and paper birch provenances came from Michigan, USA. The other progenies have been collected in European, mostly German stands or seed orchards. Some sources are commercially traded seeds. In spite of the fact that the native birches have been defeated for a long time a broad variability in mortality, growth, form of the stems and crowns etc. could be proven between the provenances and single tree progenies tested. Based on these findings forest tree breeders can feel encouraged to look for other phenotypically good provenances and their best trees in order to complete the existing clone collections for the establishment of further birch seed orchards.