The present invention relates to substituted 1,2,5-oxadiazole compounds of the formula I and the N-oxidesand saltsthereof 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 X
1 is N or CR
1 ; X
2 is N or CR
2 ; X
4 is N or CR
4 ; provided that a least one of X
1 , X
2 and X
4 is N; R is e.g. selected from the group consisting of hydrogen, cyano, nitro, halogen, C
1 -C
6 -alkyl, C
3 -C
7 -cycloalkyl, C
3 -C
7 -cycloalkyl-C
1 -C
4 -alkyl, C
1 -C
6 -haloalkyl, C
2 -C
6 -alkenyl, C
2 -C
6 -haloalkenyl, C
2 -C
6 -alkynyl, C
2 -C
6 -haloalkynyl, C
1 -C
4 -alkoxy-C
1 -C
4 -alkyl, C
1 -C
4 -haloalkoxy-C
1 -C
4 -alkyl, O-R
a , Z-S(O)
n -R
b , Z-C(=O)-R
c , Z-C(=O)-OR
d , Z-C(=O)-N R
e R
f , Z-NR
g R
h , Z-phenyl and Z-heterocyclyl; R
1 is e.g. selected from the group consisting of Z
1 -cyano, halogen, nitro, C
1 -C
8 -alkyl, C
2 -C
8 -alkenyl, C
2 -C
8 -alkynyl, C
1 -C
8 -haloalkyl, C
1 -C
8 -alkoxy, C
1 -C
4 -alkoxy-C
1 -C
4 -alkyl, Z
1 -C
1 -C
4 -alkoxy-C
1 -C
4 -alkoxy, C
1 -C
4 -alkylthio-C
1 -C
4 -alkyl, Z
1 -C
1 -C
4 -alkylthio-C
1 -C
4 -alkylthio, C
2 -C
6 -alkenyloxy, C
2 -C
6 -alkynyloxy, C
1 -C
6 -haloalkoxy, C
1 -C
4 -haloalkoxy-C
1 -C
4 -alkyl, Z
1 -C
1 -C
4 -haloalkoxy-C
1 -C
4 -alkoxy, Z
1 -S(O)
k -R
1b , Z
1 -phenoxy and Z
1 -heterocyclyloxy; R
2 , R
3 are identical or different and e.g. selected from the group consisting of hydrogen, halogen, Z
2 -OH, Z
2 -NO
2 , Z
2 -cyano, C
1 -C
6 -alkyl, C
2 -C
8 -alkenyl, C
2 -C
8 -alkynyl, Z
2 -C
3 -C
10 -cycloalkyl, Z
2 -C
3 -C
10 -cycloalkoxy, C
1 -C
8 -haloalkyl, Z
2 -C
1 -C
8 -alkoxy, Z
2 -C
1 -C
8 -haloalkoxy, Z
2 -C
1 -C
4 -alkoxy-C
1 -C
4 -alkoxy, Z
2 -C
1 -C
4 -alkylthio-C
1 -C
4 -alkylthio, etc., R
4 is selected from the group consisting of hydrogen, halogen, cyano, nitro, C
1 -C
4 -alkyl and C
1 -C
4 -haloalkyl; R
5 is selected from the group consisting of hydrogen, halogen, cyano, nitro, C
1 -C
4 -alkyl and C
1 -C
4 -haloalkyl.