Perennial; spreads by creeping rootstock; found across U.S. (not AK or CA) and southern Canada, as vine or shrub; flowers in May and June.
Entire plant is toxic. Wear protective gloves and clothing. Cut plant at base, let it dry out, and bury or put vines in trash. Do not compost or burn (inhaling smoke can be fatal). Mulch with cardboard.
Photo: (cc) H. Spauldi/Flickr
Annual/biennial; spreads by seeds; height to 5 feet; found across U.S. except southernmost Florida; flowers July through September.
Hoe or pull plants as you see them, or cut taproot below soil line. Wear gloves. Attracts beneficial insects and so may be fine for outlying areas, but can play host to lettuce diseases.
Photo: US Geological Survey USGS/Ft. Collins, CO