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Common ragweed is an annual, commonly growing to 18 inches. Found throughout the Midwest, it quickly comes up in disturbed areas or following a fire. Leaves are simple, alternate, smooth and deeply lobed. Often the lobes are lobed again. The wind-dispersed pollen is a strong allergen to many people with hay fever. It emerges in the late spring and sets seed in later summer or fall.

Common ragweed is a very competitive weed and can produce yield losses in some crops. If not controlled, the ragweed will grow and mature and produce seed in the small grain stubble. Several herbicides are effective against common ragweed, although resistant populations are known to exist.