Article from Bean's Trees and Shrubs Hardy in the British Isles
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'Rhamnus californica' from the website Trees and Shrubs Online (treesandshrubsonline.
An evergreen bush, ultimately 10 or 15 ft high; young shoots downy the first season. Leaves oblong or oval, mostly rounded at the base, rounded or broadly pointed at the apex, minutely or not at all toothed, 1 to 4 in. long, about half as wide, glabrous above, downy on the veins beneath, veins parallel, usually in eight to twelve pairs; stalk 1⁄6 to 5⁄8 in. long, downy at first, glabrous the second season. Flowers in downy, short-stalked umbels. Fruits 1⁄4 in. across, dark purple, globose.
Native of western N. America, from Oregon southwards. With some affinity to R. purshiana in the stalked flower-clusters, this is easily distinguished by its dwarfer, purely shrubby habit, its evergreen foliage, and more globose fruits.