Herbicides have negligible effects on ants and springtails in an Australian wheat field

The effects of herbicides applied to a direct drilled and traditionally tilled wheat field on trap catches of the abundant Collembola and Formicidae were examined. Significantly higher abundances of Collembola and species richness of ants were found on the direct-drilled plots. A significant effect of the herbicides, bromoxynil (C 7H 3Br 2NO) and hoegrass (diclofop-methyl), on the activity of two of the fourteen species of surface-dwelling Collembola was detected but no effect was observed on surface-active Formicidae. Jeannenotia stachi numbers were significantly more reduced on the direct-drilled compared to the traditionally tilled plot after herbicide treatment possibly because of higher predator abundance on the latter. In the short term, herbicides have a minimal effect on most species of surface-active arthropods although Collembola were more adversely affected than Formicidae.