Abstract

High performance liquid chromatography (HPLC) analytical studies of inner bark extractives from a large number of silver birch (Betula pendula Roth) and hairy birch (Betula pubescens Ehrh.) trees revealed the diarylheptanoid glucoside platyphylloside to be present at high levels in B. pendula (20-60 mg/g dry bark) and at low levels in B. pubescens (less than or equal to 0.5 mg/g dry bark). Based on these observations, a new simple and accurate precipitation method to distinguish between B. pendula and B. pubescens has been developed. In a solution of 2,4-dinitrophenylhydrazine, platyphylloside immediately forms an orange precipitate. A similar precipitate is also produced when a piece of B. pendula inner bark is kept for 1 h at room temperature in the same solution. However, no precipitate forms when a sample from B. pubescens is used. The diagnostic value of morphological characters was assessed by comparing the results of species determinations made on a large number of trees (>1600), both juvenile and mature, using the morphological and the new chemical method. For birches younger than 20 years there was 100% agreement between the two methods. However, in some mature birch stands with the two species mixed and ages over 40 years, up to 20-30% of the trees were incorrectly identified to species using morphological characters. Results from tests using the precipitation method on birch species, varieties, forms, and hybrids were reported.

Published in

Canadian Journal of Forest Research
1995, Volume: 25, number: 7, pages: 1097-1102
Publisher: NATL RESEARCH COUNCIL CANADA

SLU Authors

• Eriksson, Harry

  • Department of Forest Yield Research, Swedish University of Agricultural Sciences
    

• Johansson, Ulf

  • Department of Forest Yield Research, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Forest Science


Publication identifier

DOI: https://doi.org/10.1139/x95-121

Permanent link to this page (URI)

https://res.slu.se/id/publ/79205