Lactofen (trade name Cobra 2E) is a contact diphenylether herbicide that kills susceptible broadleaf weeds by disrupting cell membranes. It has a broad spectrum of activity an troublesome broadleaf weeds. Cobra was introduced as an over-the-top product for soybeans in 1987. While development work was still underway for the soybean label, the spectrum of control was noted to include some weeds that were difficult to control in cotton, such as prickly sida (Sida spinosa L.), spotted spurge (Euphorbia maculata) and common cocklebur (Xanthium strumarium L.). In-house and cooperative university research since that time has identified rates, timing and additives necessary to control these weeds in cotton (Gossypium hirsutum L.). Valent U.S.A. has submitted a petition to the U.S. Environmental Protection Agency for registration of Cobra 2E as a post-directed herbicide to be applied to 6-8 inch cotton. Data which supports this petition suggests that for most applications a broadcast equivalent rate of Cobra 2E at .2 lb ai/Ac plus 1 pint/Ac crop oil concentrate will be sufficient. For less susceptible species, such as morningglories (Ipomoea sp.) and sicklepod (Cassia obtusifolia), Cobra tank-mixes with MSMA and other cotton herbicides are being investigated.