The carrot fly (Chamaepsila rosae) is a pest of gardens and farms, and mainly affects the crop of carrots, but can also attack parsnips, parsley and celery. Crop damage is caused by the creamy-yellow larvae (maggots) feeding on the outer layers of the carrot root. In autumn, they may penetrate further into the root. The legless larvae are up to 10 mm in length. Foliage becomes wilted and discoloured. Leaves turn rusty red to scarlet with some yellowing. Rusty-brown tunnels are seen under the outer skin of mature roots.
Pictures show the damage a carrot fly infestation can cause and the carrot fly larvae.