A buckthorn(Rhamnus purshiana) native to northwest North America, the bark of which is the source of cascara sagrada.

药鼠李树原产北美洲西北部的一种药鼠李树（珀希鼠李鼠李属），其树皮是药鼠李皮剂的原料。

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A buckthorn(Rhamnus purshiana) native to northwest North America, the bark of which is the source of cascara sagrada.

药鼠李树原产北美洲西北部的一种药鼠李树（珀希鼠李鼠李属），其树皮是药鼠李皮剂的原料。

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