Any coarse weedy herb.
An umbelliferous plant, of genus Heracleum, most species of which are phototoxic.
Certain plants from the genera Ambrosia, Erigeron, or Heracleum.
Any of various weedy plants sometimes used as pig fodder
Polygonum aviculare (common knotgrass)
Amaranthus species
Portulaca bicolor, of Australia
Heracleum sphondylium
Chenopodium album, white goosefoot