Fig. 6 Relative importance values (%) of main weeds in the herbicide treated plots in 1998 (from left to right: lavender-cotton (Sanvitalia procumbens Lam.), Cynodon sp., Neomillspaughia emarginata, Cenchrus insertus, Ruellia nudiflora, southern sida, Elytraria imbricata R. Br. Unknown Asteraceae, bitterweed (Parthenium hysterophorus L.)