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Ragweed Identification

Ragweed Form Ragweed Leaf Ragweed Flowers Ragweed Stem
Form Leaf Flowers Stem

Common Ragweed

Scientific Name: Ambrosia artemisiifolia 
Height: 1 to 5 feet 
Stems: green, hairy 
Leaves: divided into narrow segments, each irregularly lobed. 
Flowers: 2 to 4 inch long terminal spikes of green to yellow flowers.

Interesting Notes

  • There are 17 species of ragweed in North America.
  • Ambrosia is the generic name of ragweed and in the Latin means "food of the gods."
  • Ragweed grows the best in sunny, newly-disturbed soils, free from competition with other weeds and grasses. It is often found along roadsides, vacant lots, river banks, and abandoned fields.
  • Ragweed starts blooming in Pennsylvania in mid-August as the days become shorter and the nights longer. Pollen production ends mid-September as temperatures start dropping below 60 °F.
  • It is estimated that one ragweed plant can produce up to 1 billion pollen grains.