Plants are often attacked by hundreds of parasitic insects. These insects can cause aesthetic and qualitative damage, also compromising the future vegetative recovery of the affected species. There are parasitic insects that are dangerous only in the larval stage, others that damage plants only as adults, still others are fearsome both by larvae and adults. Among the latter we must remember the oziorrinco, a beetle belonging to the family of weevils. This beetle looks very similar to the beetles that are seen coming out at night in the countryside. However, he does not limit himself to walking or collecting dung, but prefers to devour young ornamental and fruit plants. The plants we are talking about are the shrub species, the trees, in short, on which the oziorrinco and its larvae feed.
As mentioned in the previous paragraph, the oziorrinco is a beetle belonging to the weevil family. The weevils are scarabs that have a proboscis-shaped head with a mouth in the final part. Like all weevils, the oziorrinco is a phytophagous, that is, it feeds on plants. The difference between this insect and others belonging to the same family lies in the place where the females lay their eggs. Those of the oziorrinco do it under the ground, while in the other insects, above the leaves. Whether above, under the ground or the leaves, the larvae of oziorrinco and adult specimens are capable of causing considerable damage to plants. The adult beetle, in addition to the proboscis head, has a round or hemispherical back, thorax and abdomen. The back is colored black and sometimes mottled with yellow specks. The insect can be between eighteen millimeters and one centimeter in size. The larva, on the other hand, has a white body, a reddish head and the same size as the adult insect.
The adult oziorrinco attacks young fruit and ornamental trees. During the day, the insect lives hidden in the ground, where it digs shelters to lay its eggs. At night, however, it goes out into the open to hunt for food. During its long nocturnal walk, the oziorrinco climbs the tree trunk and devours the leaves, and then returns to the shelters the next morning. The larvae are also very harmful. These, overwintering in the ground, feed on the roots of the tree, causing its death. Damage to plants is both aesthetic and productive. The young seedlings, due to the action of the larvae, will no longer be able to develop, while the more adult tree will see the structure of its crown compromised. The attack of the adult insect is recognizable by the crescent erosions present on the leaves. These structures, in addition to suffering aesthetic damage, also undergo severe vegetative damage because their photosynthetic capacity is compromised.
The fight against oziorrinco is essentially biological. With this beetle, in fact, it is impossible to practice chemical control, because the infestation takes place over a period of about four months, at the beginning of summer (May-June) and at the beginning of autumn (September-October). The chemical fight against this insect would involve a massive use of very toxic fungicides. In fact, to kill it, it would be necessary to administer them continuously for at least two weeks, risking systemic damage to the plant and pollution of the environment. On the other hand, biological control is very effective, which uses methods to prevent the insect from rising along the tree trunk. To prevent the oziorrinco from reaching the leaves, the base of the trunk must be protected with special bands impregnated with natural substances that block its movement. These wraps can also be made with cardboard impregnated with natural mistletoe. The mistletoe is spread with a brush on the outer surface of the band, which will have to band precisely the circumference of the trunk starting from the base and up to a height of forty centimeters. In the absence of mistletoe you can also use other gluing substances, always natural and available in gardening shops. The beetles already present on the leaves can be eliminated by shaking the foliage and letting them fall on a cloth or a straw surface placed at the base of the tree. Once captured, specimens of oziorrinco they must be burned. On the other hand, the fight against the larvae is different. The latter live hidden in the ground and need products capable of flushing out or trapping them. Excluding a priori the use of chemical substances, which are not needed in the case of oziorrinco, products based on nematodes can be used. These are worms comprising thousands of species. Among these there are also worms antagonists of the larvae of oziorrinco. The nematodes insert themselves into the soil through irrigation tools. It should be remembered, however, that these worms act at temperatures between fifteen and thirty degrees and in well-humid and drained soils. The biological fight against the larvae of oziorrinco works, in fact, on soft and sandy soils, while it is not very effective in clayey and too compact soils, which prevent the worms from moving or crawling easily.