Carrot Grubs
(Psila rosae). The grub of the Carrot Fly, which plays such havoc among Carrots, is cylindrical, and of a pale yellow colour; the body tapers slightly towards the mouth, while the other end is rounded; its skin is smooth and shining; the tail has two little black tubercles. When the larva is full grown, it quits the Carrot, and, burrowing into the earth, becomes a pupa, light brown in colour, and oval. The perfect fly is shining black, slightly tinged with a greenish lustre. It has yellowish legs, white "balancers," and hyaline transparent wings; the head is reddish-yellow, and the antennae and palpi tipped with black.
These grubs are probably the most destructive insects that attack Carrots. They bore into the roots, causing the tops to turn brown and eventually to die. The crop is almost entirely lost in some gardens in consequence. As soon as any plants are observed to be sickly, they should be pulled up, and either burned or destroyed by some other means. Dressing the ground with lime the previous autumn, or the drills with lime and soot when sowing, is sometimes a good preventative. It is also important not to use the same ground for Carrots two successive years, especially if these insects or any wireworms are present in the soil.