Arnica Diversifolia, or more commonly know as Rayless Arnica, is a forb/herb (a forb/herb is a non-woody plant that is not a grass) with green foliage and yellow flowers of the genus Arnica. It has a moderate growth rate and a height of 1.25 feet at maturity. Its duration is perennial which means it will grow year after year. It's active growth period is summer, blooms during summer, is somewhat tolerant of shade and is routinely available commercially. Arnica Diversifolia or Rayless Arnica's floral region is North America US Lower 48, specifically in the states of Alaska, California, Idaho, Montana, Nevada, Oregon, Utah and Washington.
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