Ambrosia psilostachya

from WordNet (r) 3.0 (2006)
Ambrosia psilostachya
    n 1: coarse perennial ragweed with creeping roots of dry barren
         lands of southwestern United States and Mexico [syn:
         {western ragweed}, {perennial ragweed}, {Ambrosia
         psilostachya}]
    

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