Polygonum Capitatum, or more commonly know as Pinkhead Smartweed, is a subshrub forb/herb of the genus Polygonum. Its duration is perennial which means it will grow year after year. Polygonum Capitatum or Pinkhead Smartweed's floral region is North America US Lower 48 and Hawaii, specifically in the states of California, Hawaii, Louisiana and Oregon.
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