CBD Pure Oil then, that white willow bark is often called "herbal aspirin". Although white willow may be the species of willow tree virtually all used for medicinal uses commonly, other salicin- rich species are employed as well, including crack willow (Salix fragilis), purple willow (Salix purpurea), and violet willow (Salix daphnoides). These all may be sold under the label of willow bark.

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