How to sign: any plant that crowds out cultivated plants
Categories: tracheophyte, vascular plant
Within this category: alligator weed, Barnaby's thistle, bastard feverfew, carpetweed, cat's-ear, cocklebur, corn cockle, corn spurry, fireweed, groundsel, horseweed, jointed charlock, king devil, knawel, nettle, orange hawkweed, oxtongue, pennycress, ragweed, ragwort, sand spurry, thistle, threadleaf groundsel, tumbleweed, wild parsnip, wormseed mustard, yellow rocket