Betula celtiberica, the Iberian white birch, is a species of flowering plant in the family Betulaceae, native to Great Britain, northwestern Spain and Portugal.https://flora-on.pt/#/1betula+celtiberica In Spain is it often found on north-facing valley slopes, forming mixed mesic forests with the common beech Fagus sylvatica. Some authors, particularly in Britain, treat it as a subspecies of Betula pubescens (downy birch), with the suggestion that it is a stabilised hybrid between that and Betula pendula (silver birch).
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