Nut-Weevil
(Balaninus nucum). It has probably occurred to most persons, when eating Hazels or Filberts, to find some of the shells filled with a black, nauseous powder, instead of with the healthy kernel; or, occasionally, a fat, white maggot may be found feeding on the kernel. The cause of these disappointments is the Nut-Weevil, a curious-looking beetle remarkable for the length and slenderness of its beak, on the middle of which are situated the antennae. The beetle is about 1/3in. long. The body is egg-shaped; it is dark brown or black, but is covered with grey, yellowish-grey, or white hairs, which form irregular, oblique, paler spots on the shoulders, and on the wing-covers. The hairs can be readily rubbed off, leaving the dark ground colour visible. The beak is red-brown; it is a little thickened towards the tip, but beyond the antennae it curves downwards, slightly in the male, strongly in the female. The antennae have a long joint at the base, followed by a number of short ones; the end ones are thicker, so that they form a knob at the tip. There is a sharp bend, like an elbow, formed just at the tip of the long joint.
In June, when the nuts are about half-grown, the female Weevils may be found boring holes in the still soft nutshell. One egg is laid in each nut, and it is pushed, by aid of the long beak, into the nut. The hole very quickly closes up, and hardly a scar even can be detected. From the egg emerges a little grub, which feeds upon the seed or kernel, and leaves, in its stead, only a mass of dark, powdery excrement. The grub is yellowish-white, wrinkled, and footless, and lies curled round on one side. Its head is small, and yellowish-brown. When full-fed, it eats a round hole through the shell of the nut, falls to the earth, and burrows under it, there to become a pupa. The beetles emerge from the soil in May of the following year; and, for a time, they feed on the young buds of the Hazel-bushes.
Remedies. When the nuts are attacked, the grubs cannot be detected or removed, except when the nuts fall from the bushes. The latter should be well shaken during the autumn, occasionally; and all the nuts that fall should be gathered and burned, before the grubs come out. In April, and the beginning of May, gas-lime or soot may be scattered below the bushes, in preparation for the beetles coming up from the soil. Beating the bushes in dull weather will cause the beetles to fall from the branches; and tarred boards, or other appliances, to prevent their escape, should be placed below, to receive them when they fall; or they may be swept up at once from cloths laid on the soil. It is well not to allow wild Hazel-bushes to grow near plantations of cultivated Hazels or Filberts.