Cornus coreana Wang.

Cornus coreana is extremely close to the Chinese species Cornus walteri (see that entry), but was described from Korean material (Wangerin 1908), and is distinguished by its smaller flowers and darker bark colour (Xiang & Boufford 2005). E. H. Wilson noted that the mature bark of the Korean trees he saw developed a characteristic mosaic-like pattern, ‘deeply fissured into tiny squares’ (Wilson 1919), as seen in a remarkable 1917 photograph of a forest specimen from Goryeo, central Korea in Wilson’s archive (N-167) – the girth is more than 2 m. It is unclear whether this tessellated effect – which is not noted in the Cornus walteri literature – is a universal character in C. coreana. It appears from Wilson’s image that such rectangular-platy bark may represent a progression from an intervening longitudinally ridged, ‘shaggy’ condition familiar from C. walteri. Greater familiarity with the range of variation present in wild trees of different ages is needed to assess the significance of Wilson’s observation.

A series of introductions were made from Korea to the United States in the late 1920s, several from Seoul (Keijo), among which two cultivated trees from the Imperial Gardens collected in 1929, Dorsett & Morse 1550 and 1633 (introduced under PI 82070 and 82071), and PI 78401 in 1928. PI 82475 was imported from Hyesan (Heizan) – in what is now North Korea – in 1929 (United States Department of Agriculture 1929). For obvious reasons, recent introductions have come from South Korea only: several arboreta grow material from Mount Odae (Odae San), Gangwon Province in central Korea, from (apparently) wild-collected seed offered in 1989 by Chollipo Arboretum (see the images below from Wespelaar Arboretum). Howick Arboretum holds ChA 867 from Naeyeonsan in North Gyeonsang Province, and the UBC Botanic Garden, Vancouver and US National Arboretum (among others) grow KSW 3653 from the Arboretum’s 1895 Expedition to southwest Korea, collected on the Byeonsan-bando peninsula. At the Castle Howard Arboretum there are several specimens of BECX 257, collected as seed in 1982 from 8 m tall trees growing at 100 m asl in Gaeryong san National Park, Chungchong Nam do Province, South Korea; these have formed undistinguished multistemmed specimens, though it is worth noting that the bark shows signs – in the form of incipient lateral striae – of beginning to break up into the rectangular tile-like plates noticed by E. H. Wilson (this character is also noticeable on trunk images of a tree grown at the Arnold Arboretum, 1391–63*A).