Some botanists recognize a 3rd species in Central Yukon called Cornus unalaskensis. It also goes by C.canadensis var. intermedia.
This species or variety is of hybrid origin between a species found in Alaska called C.seucica and the regular C.canadensis.
It has charactaristics of both species, has reduced or no fertility and reproduces vegitatively.
It's range extends farthur east than that of C.seucida and is thought to be left over from an earlier climactic period.
This variety is treated as a hybrid here and is discussed on the Cornus canadensis (Bunchberry) page.
Illustrated Key To Family
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