The information in this profile may be out-of-date. It was last revised in 1996. EXTOXNET no longer updates this information, but it may be useful as a reference or resource.

Please visit the National Pesticide Information Center (NPIC) to find updated pesticide fact sheets. If you don't find a fact sheet related to your question, feel free to call 1-800-858-7378. NPIC is open five days a week from 8:00am to 12:00pm Pacific Time.


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Pesticide Information Profiles

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TRADE OR OTHER NAMES: The active ingredient acetochlor is found in a variety of commercial herbicides. Some trade names for products containing acetochlor include Acenit, Guardian, Harness, Relay, Sacemid, Surpass, Top-Hand, Trophy and Winner (205, 206, 207). Most formulations come as emulsifiable concentrates.

REGULATORY STATUS: Acetochlor has a conditional registration in the United States to the Acetochlor Registration Partnership (ARP) composed of Monsanto Co., The Agricultural Group and ZENECA Ag. Products. The registration allows for automatic cancellation if use of several alternative corn herbicides is not reduced by a specified amount. Groundwater contamination may also be grounds for cancellation. Acetochlor is considered a restricted use pesticide (RUP) with a toxicity classification of I (Highly toxic). Check with specific state regulations for local restrictions which may apply. Products containing acetochlor must bear the signal word "Danger" on their label (206).

INTRODUCTION: Acetochlor is used for control of most annual grasses and certain broadleaf weeds and yellow nutsedge. Crops include cabbage, citrus, coffee, corn (all types), cotton, green peas, maize, onion, orchards, peanuts, potatoes, rape, soybeans, sugarbeets, sugarcane, sunflower, and vineyards. Acetochlor is applied preemergence, preplant incorporated and is compatible with most other pesticides and fluid fertilizers when used at recommended rates. Usually 0.3-0.6 inches of rainfall will activate the product if it occurs within 7-10 days (205, 206, 207, 210).





Physical Properties:

Exposure Guidelines:


Monsanto Co.
800 N. Lindbergh Blvd.
St. Louis, MO 63167
Telephone: 314-694-6640
Emergency: 314-694-4000

ZENECA Ag Products
1800 Concord Pike
Wilmington, DE 19897
Fax: 302-886-1552
Telephone: 800-759-4500
Emergency: 800-759-2500


References for the information in this PIP can be found in Reference List Number 10

DISCLAIMER: The information in this profile does not in any way replace or supersede the information on the pesticide product label/ing or other regulatory requirements. Please refer to the pesticide product labeling.