Betula × aurata Borkh.

Synonyms

B. × hybrida Blom, B. × obscura Kotula

Article sources

New Trees

This taxon is the hybrid progeny of two European native birches, B. pendula Roth. and B. pubescens Ehrh. However, it often occurs in the absence of one or both parent species, a testament to the capacity for dispersal of birch seeds and pollen. Betula ×aurata is intermediate between the parent species in its morphology, but identifying the hybrid can be challenging. It can be sterile or fully fertile, and can therefore form hybrid swarms through backcrossing with the parent species – especially the tetraploid B. pubescens (the diploid B. pendula can often be identified as remaining ‘pure’ in hybrid swarms) – producing a confusing range of morphologies. Because of these difficulties with identification, the distribution of the hybrid is uncertain. Stace 1997. Distribution UNITED KINGDOM. Habitat Disturbed areas and secondary vegetation. USDA Hardiness Zone 3. Conservation status Not evaluated. Cross-reference K222.

This hybrid is occasionally found in collections – as, for example, one old specimen at Edinburgh – and more frequently where the parents meet in the wild. It is generally of scientific interest only.

Genus

Betula

Other species in the genus