The present invention relates to substituted 1,2,5-oxadiazole compounds of the formula I and the N-oxides and salts thereof and to compositions comprising the same. The invention also relates to the use of the 1,2,5-oxadiazole compounds or of the compositions comprising such compounds for controlling unwanted vegetation. wherein X1 is N or CR1； X2 is N or CR2； X4 is N or CR4； provided that a least one of X1, X2 and X4 is N； R is e.g. selected from the group consisting of hydrogen, cyano, nitro, halogen, C1-C6-alkyl, C3-C7-cycloalkyl, C3-C7-cycloalkyl-C1-C4-alkyl, C1-C6-haloalkyl, C2-C6-alkenyl, C2-C6-haloalkenyl, C2-C6-alkynyl, C2-C6-haloalkynyl, C1-C4-alkoxy-C1-C4-alkyl, C1-C4-haloalkoxy-C1-C4-alkyl, O&mdash；Ra, Z&mdash；S(O)n&mdash；Rb, Z&mdash；C(&boxH；O)&mdash；Rc, Z&mdash；C(&boxH；O)&mdash；ORd, Z&mdash；C(&boxH；O)&mdash；NReRf, Z&mdash；NRgRh, Z-phenyl and Z-heterocyclyl； R1 is e.g. selected from the group consisting of Z1-cyano, halogen, nitro, C1-C8-alkyl, C2-C8-alkenyl, C2-C8-alkynyl, C1-C8-haloalkyl, C1-C8-alkoxy, C1-C4-alkoxy-C1-C4-alkyl, Z1&mdash；C1-C4-alkoxy-C1-C4-alkoxy, C1-C4-alkylthio-C1-C4-alkyl, Z1&mdash；C1-C4-alkylthio-C1-C4-alkylthio, C2-C6-alkenyloxy, C2-C6-alkynyloxy, C1-C6-haloalkoxy, C1-C4-haloalkoxy-C1-C4-alkyl, Z1&mdash；C1-C4-haloalkoxy-C1-C4-alkoxy, Z1&mdash；S(O)k&mdash；R1b, Z1-phenoxy and Z1-heterocyclyloxy； R2, R3 are identical or different and e.g. selected from the group consisting of hydrogen, halogen, Z2&mdash；OH, Z2&mdash；NO2, Z2-cyano, C1-C6-alkyl, C2-C8-alkenyl, C2-C8-alkynyl, Z2&mdash；C3-C10-cycloalkyl, Z2&mdash；C3-C10-cycloalkoxy, C1-C8-haloalkyl, Z2&mdash；C1-C8-alkoxy, Z2&mdash；C1-C8-haloalkoxy, Z2&mdash；C1-C4-alkoxy-C1-C4-alkoxy, Z2&mdash；C1-C4-alkylthio-C1-C4-alkylthio, etc., R4 is selected from the group consisting of hydrogen, halogen, cyano, nitro, C1-C4-alkyl and C1-C4-haloalkyl； R5 is selected from the group consisting of hydrogen, halogen, cyano, nitro, C1-C4-alkyl and C1-C4-haloalkyl.La présente invention concerne des composés
