Preplant weed control

paraquat (Gramoxone SL 2.0 and other trade names)

Rate 0.5 to 1 lb ai/A (2 to 4 pints/A Gramoxone SL 2.0)

Time Apply to emerged weeds 1 to 6 inches tall, but before crop emerges.

Remarks Form seedbeds as far ahead of treatment as possible to permit maximum weed emergence. Use the higher rate for heavier weed populations. It is essential to obtain complete coverage of target weeds to obtain good control. Can be used in fallow bed/stale seedbed for weed control. Seeding should be done with a minimum amount of soil disturbance. Add a nonionic surfactant containing 80% or more active ingredient at a minimum of 0.125% v/v (1 pint/100 gal spray). A nonphytotoxic crop oil concentrate or methylated seed oil containing 15 to 20% approved emulsifier may be used at 1% v/v (1 gal/100 gal spray). Rain occurring 15-30 minutes or more after application will have no effect on Gramoxone SL activity. REI 24 hr.

Caution Restricted use pesticide due to acute toxicity for retail sale to and use only by certified applicators - not to be used by uncertified persons working under the supervision of a certified applicator. Wear a long-sleeved shirt, long pants, shoes and socks, protective eyewear, chemical-resistant gloves (Category A), and a NIOSH-approved respirator with any N, R, P, or HE filter when handling and spraying. Avoid contact with eyes and skin. Do not breathe spray mist. Do not allow spray to drift from target site.

Site of action Group 22: photosystem I electron diversion

Chemical family Bipyridilium

glufosinate-ammonium (Ignite 280SL, Rely 280, Liberty 280 SL and other trade names)

Rate 0.59 to 0.66 lb ai/A (32 to 36 fl oz/A Liberty 280 SL)

Time Apply to emerged weeds 1 to 6 inches tall, but before crop emerges.

Remarks Apply to actively growing small weeds and use a minimum spray volume of 15 gal per acre to ensure uniform, thorough spray coverage. Warm temperatures, high humidity, and bright sunlight improve weed control efficacy. To avoid the possibility of reduced weed control, applications must be made between dawn and 2 hr before sunset. Weed control may be reduced if application is made when heavy dew, fog, and mist/rain are present; or when weeds are under stress due to environmental conditions including drought, cool temperatures, or extended periods of cloudiness. Ammonium sulfate (AMS) can be used at 1 .5 lb/A to 3 lb/A. AMS improves weed control under difficult environmental conditions (low relative humidity) or hard water.

Caution. Do not apply more than 36 fl oz/A (0 .66 lb ai/A) per year for non glufosinate-resistant sugar beet. Do not make more than one application per year.

Site of action Group 10: glutamine synthase inhibitor

Chemical family Phosphinic acid