Sunday, 8 November 2020

Asian Dogwood (Cornus koenigii)

Its been just over 10 years now since Peter Sell first brought attention to the fact that that Dogwood (Cornus sanguinea), as understood by British botanists, included two non-native taxa i.e. Southern Dogwood (Cornus australis or sanguinea subsp. australis depending on preference) and Asian Dogwood (Cornus koenigii). Both of which were subsequently picked up from Stace 3 onwards.

Southern Dogwood is very widely planted, indeed many if not most 'native' plantings will be this and on this basis I think dogwood should be avoided in native planting mixes. Clearly growers are making no effort to distinguish native from non-native. As well as planted occurrences, it is also rapidly and aggressively spreading by seed from plantings. For example, it is increasingly being found in semi-natural habitats in Eastern England and West Yorkshire. In my opinion, it is still under-recorded in lowland England, and until more recorders split them (which is quite easy, only requiring a check of the hairs on the underside of the leaf) we won't truly understand how far it has established. Once known it can usually be told at a glance, although the hairs should always be checked.

In comparison, Asian Dogwood is much less commonly seen and of more patchy occurrence. I usually only see it planted into the wild and it seems less inclined to self-sow. So it was interesting to find a bush locally that is clearly of bird sown origin (there are mass-plantings within a few 100m as the berry-eating bird flies).



Asian Dogwood also has a very distinct jizz and can usually be told at a glance. As with Southern Dogwood it can form a large robust bush, but is generally less densely branched and in foliage, and the leaves have hairs like Dogwood. The leaves are typically large (much larger than Dogwood except where this is shade grown, and usually but not reliably larger than Southern Dogwood), clearly longer than wide (some forms of Southern Dogwood can have quite a rounded leaf outline in comparison), and have a markedly acute apex. The petioles are also very long relative to the other two species.




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