Article from Bean's Trees and Shrubs Hardy in the British Isles
Recommended citation
'Cornus occidentalis' from the website Trees and Shrubs Online (treesandshrubsonline.
A deciduous shrub 6 to 18 ft high in a wild state, with glabrous, purple branches. Leaves opposite, narrowly oval or ovate, 11⁄2 to 4 in. long, 3⁄4 to 2 in. wide, tapered or somewhat rounded at the base, blunt or pointed, rarely slender at the apex; dark green and slightly hairy above; pale and woolly beneath. Flowers yellowish, crowded densely in compact, rounded, downy cymes about 2 in. across. Fruit white.
Native of British Columbia south to California; introduced in 1874. It blossoms towards the end of May and in June, and is pretty then. It is also distinct in its dark purplish branches and in its leaves, woolly beneath. It is allied to C. stolonifera and not easy to distinguish from it, owing to the existence of natural hybrids (or perhaps intermediates) between the two (see below).
Synonyms
C. torreyi S. Wats