Allergy Suffer's Worst Nightmare

ambrosia trifida, buffalo weed or giant ragweed, is a very competitive native plant that grows 3-12 feet tall. it is the major cause of hayfever in north america.

it depends on the wind for pollenation and attracts few insects. it has herbal uses, and oil from its seeds is rich in linolenic acid. also, a red dye can be obtained from its crushed flower heads.