MSMA
Action/Use:
- Herbicide
Use:
Preplant in cotton, bearing citrus (except Florida), nonbearing orchards. Postemergent for johnsongrass, other grassy weeds and cocklebur in cotton. For crabgrass, broadleaf control in turf.
Identification
Common Name(s): MSMA (WSSA for monosodium salt)
Chemistry
Class: Organic arsenical.
Properties: Tech: clear light yellow liquid; practically odorless. Boiling point >100°C.
Mode of Action / Resistance Management
Chemical Group: organoarsenical
Mode of Action: unknown
Action Group: HRAC Group Z; WSSA Group 17
Registration
U.S.A.: US EPA phases out MSMA. All uses except for cotton will be canceled in two phases. 1) Many uses were canceled September 30, 2009. 2) Golf courses, sod farms, highway rights-of-way will be canceled December 31, 2012 with use of existing stocks permitted through 2013.
Outside U.S.A.: Mesamate*, Diumate*.
Environmental Guidelines
Hazards: Fish: LC50 >167 mg/l (trout), >51 mg/l (bluegill). Bee: 68 µg/bee
Water Solubility: Very soluble
Safety Guidelines
Signal Word: CAUTION
Toxicity Class: III
Toxicity: (Rat): Oral LD50 1359 mg/kg; Inhalation LC50 >20 mg/l (4 h). (Rabbit): Dermal LD50 >2500 mg/kg. Mild eye, skin irritation
Handling/storage Cautions: Stable under moderate conditions
Protective Clothing: Long-sleeved shirt and long pants. Chemical-resistant gloves. Chemical-resistant apron when cleaning equipment, mixing, or loading. Approved respirator.
Suppliers and Branded Products
Basic Producers:
Ancom Crop Care S.B. (Ancosar*, Ansar*)
Crop Care Australasia Pty. Ltd. (Daconate*)
Luxembourg Industries Ltd. (Target*, Target* Plus)
Luxembourg-Pamol, Inc. (Target*, Target* Plus)
Pilar AgriScience (Canada) Corp. (Pilar-msma*)
Formulators' Trade Names:
Inquiport, S.A. (Konate*)
Insecticidas Internacionales, C.A. (Initox*)
Proficol (Master*)
B.V. Industrie- & Handelsonderneming Simonis (Wopro-MSMA*)
Premix Products:
+ Cacodylic Acid+ Sodium Cacodylate
- Herb-All*
+ 2,4-D+ Diuron
- Dasatox* — Ancom Crop Care S.B.
+ Diuron
- Monex* — Ancom Crop Care S.B.
Discontinued Names:
Arsonate Liquid*
Broadside*
Check-Mate*
Croak*
Dal-E-Rad*
Dessecan*
Diumate*
Drexar* 530
Fortex*
120 Herbicide
912 Herbicide
Merge 823*
Millennium Ultra Plus*
Moncide*
Monex* 3
Phyban* H.C.
Pilar*
Silvisar* 550
Super Arsonate*
Trans-Vert*
Trimec* Plus
Vegabate*
Weed-E-Rad*
