3,6-dichloro-2-methoxybenzohydroxamic acid derivatives and use as herbicidal agents

A compound of the formula:

• ##STR20## wherein A is O-alkylene of 1 to 5 carbon atoms, O-alkenylene of 3 to 6 carbon atoms in which the unsaturation is non-adjacent the oxygen atom thereof or NH-alkylene in which the alkylene is 1 to 5 carbon atoms, the O-- and NH-- thereof being attached to the NH which is adjacent to A,
• Z is oxygen or sulfur,
• R is H, C.sub.1 -C.sub.12 alkyl, C.sub.3 -C.sub.8 alkenyl, C.sub.3 -C.sub.8 alkynyl, C.sub.2 -C.sub.10 haloalkyl containing 1 to 6 halogens of atomic weight of 18 to 80, C.sub.2 -C.sub.10 alkoxyalkyl, cycloalkyl or cycloalkenyl of 3 to 8 ring carbon atoms optionally substituted by 1 or 2 halogens of atom weight of 18 to 80 or C.sub.1 -C.sub.2 alkyl groups, cycloalkylalkyl or cycloalkenylalkyl of 4 to 10 carbon atoms in the alkyl portion is of 1 to 3 carbon atoms and the cycloalkyl or cycloalkenyl ring is of 3 to 8 carbon atoms and is optionally mono- or di-ring substituted by halo of atom weight of 18 to 80 or C.sub.1 -C.sub.2 alkyl groups or ##STR21## m is 0 to 3, R' and R" are independently H, C.sub.1 -C.sub.4 alkyl, C.sub.1-4 alkoxy, C.sub.1 -C.sub.4 alkylthio, CF.sub.3, halo of atomic weight of from 18 to 80 or NO.sub.2,
• R" is H, C.sub.1 -C.sub.3 alkyl or halo of atomic weight of 18 to 80, or
• two of R', R" and R'" together form C.sub.1 -C.sub.2 alkylenedioxy with the other being H, in non-salt or in salt form.