A completely revised edition of Williams' previous work with the late Ruth Ashton Nelson. this edition uses simple and clear keys to identify more than 350 species of plants found in the Rocky Mountain region from the United States to Canada.
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A completely revised edition of Williams' previous work with the late Ruth Ashton Nelson. this edition uses simple and clear keys to identify more than 350 species of plants found in the Rocky Mountain region from the United States to Canada.
Read Less