^BGenetically modified maize.^b Tractor in a field of genetically modified (GM) maize plants ^IZea ^Imays,^i during a field trial. This GM maize has had one application of a Glyphosate type herbicide to which it is resistant but which has killed weeds. This herbicide is neutralised on contact with the soil and leaves no groundwater pollution which is a problem with herbicides used with non- GM maize. The GM maize has had its DNA (^Ideoxyribonucleic acid^i) genetic code modified to withstand the new herbicide. It is controversial whether GM foods are healthy to eat. This field trial was conducted by Agrevo in Lincolnshire, England.