Home › A › Apple or Codlin Grub

Apple or Codlin Grub

(Carpocapsa pomonana). During the month of May, the well-known Codlin Moth lays its eggs in the calyces, usually one in each, of the young, quickly-growing apple. The moth itself is a small insect; the fore-wings are grey, prettily speckled with delicate, darker streaks, and with a curved golden mark on the hinder part, inclosing one of a reddish-brown colour. The hind wings are usually dark, as is also the body. The caterpillar, when hatched, is white, with black head and neck, and with four rows of black marks along the whole body. The colours soon, however, become less decided, taking an indistinct brownish or grey hue. After being hatched, the caterpillar gnaws its way down the fruit, keeping clear of the core, and gradually forces its gallery towards the rind of the fruit, which it finally pierces, the opening serving as the outlet for the dirt. When nearly full grown, it pierces the core and feeds upon the pips, which injury speedily causes the fruit to drop. The insect then emerges therefrom, and finds a suitable shelter in a cranny of the bark, where it spins a cocoon; and, according to British authorities, it remains in the larval state for some weeks, finally assuming the chrysalis form, and thus passing the winter; the moth emerges the following season. Shortly after development, the moths pair, the female depositing eggs in the fruit in June or July, according to the season.

Practically, there is no preventive; but the following hints will serve to greatly reduce the numbers. All apples that fall ere they are ripe should be picked up as promptly as possible, and be given to the pigs; or pigs should be turned into the orchard to clear off the fallen fruit. The following is the only serviceable remedy:

Hayband Trap. This is simply a loosely made hayband twisted around the stems of the trees, about 1ft. from the ground. The grubs, in searching for a suitable place in which to make a cocoon, will generally choose the bands. At the end of the season, all the haybands should be collected and burnt, and the stems of the trees from which they were removed should be cleared of any cocoons which may adhere to them. All loose bark and other rubbish should be removed from the tree trunks, and also from the ground below.