Patent ID: 6908882

Claim:
A method of enhancing herbicidal activity of a glyphosate herbicide, comprising adding to said glyphosate herbicide a first surfactant and a second surfactant at a weight ratio of total surfactant to form a composition consisting essentially of glyphosate, a first surfactant, and a second surfactant to glyphosate acid equivalent of about 1.30 to about 2:1, wherein said first surfactant has a chemical structure comprising a cationic or protonatable amino group and a C 8-24 hydrocarbyl group, and said second surfactant has the chemical formula R—CO—NR′—(CR′ 2 ) n —COOM where R is a C 7-23 hydrocarbyl group, n is 1 to 4, M is hydrogen or a cationic counterion, and R′ groups are each independently hydrogen, C 1-4 alkyl or a group —(CH 2 ) m —COOM where m is 1 to 4 and M is as defined immediately above, with the proviso that no more than one R′ group is such a group —(CH 2 ) m —COOM and the weight ratio of said first surfactant to said second surfactant being about 1:10 to about 10:1.