Pyrithiobac (Staple) was developed and is registered for use as a postemergence herbicide in cotton (Gossypium hirsutum L.). It is low in mammalian toxicity, has a low leaching potential, and effectively controls common cocklebur (Xanthium strumarium L.), pigweeds (Amaranthus spp.), and other broadleaf weeds. However, it is less effective on large morningglories (Ipomoea spp.) and does not control sicklepod (Cassia obtusifolia L.). An additional tank-mix herbicide may be necessary to overcome these weaknesses.