In the pathways eaten by the larvae of the Carrot Fly, you can find droppings which lend a rusty coloring to affected plant parts. When the larvae start eating, you can find rusty coloring on the root tips even at an early stage of infestation. If seedlings become infested, they die. Heavy infestation can lead to limited water circulation and the general withering of affected plants. Carrot Flies have a length of between 4 and 5 mm. Head, legs and antennae are yellow. Carrot Fly larvae are 0.5 to 0.7 mm in size, white-yellowish and shiny.
The flies hibernates as pupae at a depth of 5 to 8 cm in the soil. The first generation of Carrot Flies start flying in spring, the second from late summer until the first frost.
Cover your carrot beds with cultivation protection nets to protect them against Carrot Fly.
Use Lambda-Cyhalothrin to fight Carrot Flies.