GB1097713A - Improvements in or relating to herbicidal compositions - Google Patents

Abstract

A herbicidal composition, especially suitable for the post-emergent inhibition or destruction of annual and perennial broad-leafed weeds growing in an arable tract of land which contains a graminaceous or leguminous crop (e.g. cereals, clover, alfalfa, peas or beans), comprises (1) at least one benzonitrile derivative of formula <FORM:1097713/A5-A6/1> wherein R1 and R2 are hydrogen atoms, R3 is a halogen atom, R5 is a halogen atom or a nitro group and R4 is a hydrogen atom or an acyl group (derived in theory by the removal of an OH group from the COOH group or sulphonic acid group of a C1-C12 aliphatic carboxylic acid, an aromatic carbocyclic carboxylic acid or an aromatic sulphonic acid), or an alkali metal, alkaline earth metal, ammonium or amine salt of a compound of the above formula wherein R4 is a hydrogen atom, together with (2) at least one herbicide which is a phenoxyalkanoic acid in the form either of the free acid or of a salt or ester thereof, the weight ratio (1): (2) being in the range 1-8: 2-20 (calculated on the basis of the free phenol for the first component and the free acid for the second component). Ingredient (2) may be MCPB, 2,4-DB, 2,4-D, MCPA, CMPP or 2,4-DP. The composition may contain solid diluents (e.g. aluminium silicate, talc, calcined magnesia, kieselguhr, tricalcium phosphate, powdered cork, absorbent carbon black and clays such as kaolin or bentonite), liquid diluents (e.g. water, tetrahydrofurfuryl alcohol, acetophenone, cyclohexanone, isophorone, dimethylformamide, ethylene glycol monomethyl ether, toluene, xylene or mineral or fatty oils) and/or surface active agents. The composition may be applied in the form of wettable powders, solutions, dispersions, emulsions or aerosols. Application may be at the rate of 1-8 ozs./acre of ingredient (1) (calculated as the free phenol) and 2-20 ozs./acre of ingredient (2) (calculated as the free acid).