#$%^&*AU2013263706A120150611.pdf#####ABSTRACT The present invention relates to a method of controlling weeds in a crop fields, land under perennial crops, or a non-crop 5 land, the method comprising applying an effective amount of crystal of flumioxazin which shows a powder X-Ray diffraction pattern having diffraction peaks with 20 values (0) shown in Table 1, said pattern being obtained by CuKce rays diffraction analysis, 10 Table 1 20 value (0) 9.8 +0.1 11.4 +0.1 12.7 +0.1 13.8 +0.1 16.0 +0.1 16.4 +0.1 16.7 +0.1 to soil where the weeds are grown or to be grown, or weeds. According to the present invention, a wide range of weeds can be controlled in a crop field, land under perennial crops, or a non-crop land.