Common Ragweed (Ambrosia artemisifolia). Asteraceae. August 16, 2020 1500 × 1200 Common Ragweed (Ambrosia artemisifolia). Asteraceae. Native, invasive. Fields, roadsides. Throughout. Napeague, Aug 2019. Native, invasive. Fields, roadsides. Throughout. Long Island, August, 2019.