Otiorhynchus
A genus of beetles, belonging to the group of Weevils, with short beaks, and long-elbowed, twelve-jointed antennae, inserted in front of the eyes; well-formed elytra, soldered together, with usually ten rows of small, shallow pits or dots along each, no wings, and simple claws. There are numerous species, mostly about 1/3in. to 1/2in. long, by half as much broad. One or two do not exceed 1/5in. in length. They are all black or brown in colour, with the legs in some black, in others dull red. They are so much alike that it is very difficult to distinguish some of the species from each other. The following are among the more destructive kinds: O. picipes (the Pitchy-legged Weevil), 1/3in. long, pitch-brown, or earth-coloured, with the upper surface tubercled, and sprinkled with minute pale grey or yellow scales. Each pit in the rows on the elytra has a whitish scale, like the pupil of the eye, in the middle. The legs and antennae are usually rather paler than the body; each thigh is toothed. O. raucus is much like the last in size, but may be distinguished by a slight ridge down the middle of the thorax, the dots of the elytra being deeper, and not having white scales, by the black body being clouded with yellow and grey pubescence, and by the red-brown legs and antennae, and the unarmed thighs. O. sulcatus (the Black Vine Weevil) is black or dark brown in colour, with greyish-yellow tufts of hair on the deeply-furrowed elytra. The thorax is coarsely tubercled, and has a slight furrow down the middle; the beak is deeply grooved, and the thighs are toothed. This insect measures about 2/5in. in length. O. tenebricosus (the Red-legged Garden Weevil) is said to be one of the most destructive, as well as the largest species of the genus, being about 1/2in. long. It is at first black, dotted with tufts of delicate yellow down; afterwards glossy. The elytra are only slightly striated; the legs are red-brown or chestnut, and the beak is notched at the tip, and faintly ridged. O. ligustici is about 2/5in. to 1/2in. long; it is black, with greyish scales. The thorax and the almost unstriated elytra are finely granulated, and the thighs bear a short tooth. Other species also have been detected injuring plants, but are less common and less hurtful than the above. The species in this genus are destructive both as perfect beetles and as larvae. The beetles feed on buds or young shoots of Vines, Peaches, Apricots, and other choice fruit-trees, as well as on the young shoots of Raspberries; and Curtis, in "Farm Insects," mentions O. picipes as being very destructive to Peas, Turnips, Kale, &c. In consequence of the damage done, the injured parts are destroyed in a short time; and the plants may be killed, or, at least, much crippled, so as to greatly diminish their productiveness. The larvae are frequently most injurious to the roots of plants of various kinds, such as Raspberries, Strawberries, and other fruit-bearing plants, as well as to roots of a great variety of other plants in gardens; e.g., Primroses, Sedums, Saxifrages, &c., upon the shoots of which the beetles also feed. The larvae never show themselves above ground; hence, the only sign of their presence is the withering of the plants. They frequently do great harm to potted plants in greenhouses. They become pupae about 3in. or 4in. below the surface of the soil.
Remedies. As the beetles are wingless, their attacks are usually limited in area, and the damage can be much restricted by suitable means, of which the most successful are those directed against the perfect insects. As all the species have very similar habits, the same methods of destruction apply to all. The beetles conceal themselves by day in holes in walls, or under loose mortar and stones, among dead leaves, in the soil, or in any other convenient retreats, such retreats varying with the nature of the crop attacked by them, and with the habitat. At night, they come out to feed, and, owing to their not possessing wings, they require to creep up the plants to arrive at the young shoots and buds; or else, in the case of Vines, and other plants trained against walls, they may gain access to them by crawling over the walls. Prevention may be secured by the removal of all cover, such as loose mortar on walls, dead leaves, or bark, &c., and stopping up holes in the walls. This should be followed by putting a belt of soft soap, or tar mixed with oil, round the tree stems, and along the base of the walls against which Vines and other plants liable to injury are trained. Gas-lime on the soil, or soot or lime, would probably be of service, by preventing the passage of the beetles; and these applications, with or without paraffin or carbolic acid solutions, or gaswater, would help to destroy the larvae in the soil around the roots of plants. Where a Vine border is badly infested, the best course is to remove the soil to a depth of 5in. or 6in. replacing it with new material. Where the beetles are numerous, and destructive to buds and shoots, it is necessary to use means for their capture. They fall very readily off their food-plants when these are shaken, or when a light is brought into their vicinity. Hence, it is advisable to lay cloths or papers, or to invert an open umbrella beneath the plants, which should then be shaken, and the fallen beetles swept together and killed by means of boiling water; or they may be shaken into rough trays tarred inside. When plants turn sickly without evident cause, investigation should be made, and, if larvae are found, they should be destroyed.