The weevil beetle belongs to one of the many species of the Coleoptera family. Very often they are called elephants or mowers. Such a harmless name hides one of the most dangerous insects, destroying almost all known species of flora. The weevil family (lat. Curculionidae) belongs to the order Coleoptera, one of the largest among this species of beetles. Their number reaches seventy thousand. Elephants mainly live in tropical countries. About five thousand species of beetles have been recorded in Russia.
Pests of fields, gardens and vegetable gardens
The elephant beetle (another name is the mower) is a representative of the Coleoptera family. The harmless name hides one of the most dangerous insects, capable of destroying almost all existing plant species in the shortest possible time.
Weevils (from the Latin Curculionidae) belong to the order Coleoptera, one of the largest families of beetles. There are more than 70 thousand of them on the globe. The priority habitat for insects is countries with a hot tropical climate. More than 5 thousand species of weevils have been recorded in Russia.
Appearance
Representatives of the fauna are mostly small bugs, not exceeding 8-10 millimeters in length. Only certain species of tropical inhabitants can grow to truly gigantic sizes - up to 5-6 centimeters. The appearance of adults can vary significantly depending on habitat, feeding habits and potential threats. Species classification divides beetles into the following groups:
- by dimensions;
- by body shape (spherical, diamond-shaped, pear-shaped, rod-shaped);
- by the color of the chitinous cover (the color range is wide, some individuals have a specific coating on the skin of pollen or scales).
Anatomical features
The entire family of mowers, depending on the structure of the front part of the head, called the rostrum, can be divided into the following types:
- Long-proboscis. The rostrum is elongated, in most specimens it is curved and thinned towards the apex. The larvae live on plant branches or spreading leaves.
- Short-proboscis. The rostrum is small in size, it does not exceed twice the width of the base. In the ground the larvae feel protected.
In adults, the oral apparatus is located at the end of the proboscis. Elbowed antennae with a characteristic club grow from the apical recesses.
Female insects are larger than males and are physically more advanced. There are species without external sexual differences. An adult female, ready to reproduce, gnaws holes in the tissues of leaves or stems and lays eggs there. There can be 25-30 larvae in one clutch.
Life cycle
Male elephant beetles are distinguished by their ferocious disposition and stage entire battles for the right to fertilize a female, trying to hook each other with their horns and throw them on their backs. A fertilized female lays 12-20 eggs in the trunk of an old rotten tree to a depth of 25 cm. The embryonic stage of egg development lasts about a month, then the larvae appear. They are quite unpretentious in food and feed on any wood rot, quickly gaining weight. In a year and a half, they can gain weight up to 100 g and go through several developmental phases before pupating.
The formation of the pupa occurs within 2-3 months, after which it darkens, and then the process of hatching the beetle begins, which can last up to 2 days. Emerging adults have soft white elytra, which harden and darken within 4 days, and the elephant beetle takes on its final appearance. The lifespan of adults, as a rule, does not exceed 4 months.
Weevil larvae
Long-proboscis representatives of the species lay eggs in apples, nuts and other fruits. Short-proboscis relatives develop in the soil, where they feed on plant roots. The worm-like body is thickened and fleshy. The shape of the larva is curved, resembling the letter “C”. The outer shell is covered with sparse bristles. The head is covered with a dense, dark-colored chitinous shell. The deterioration of the condition of a young individual can be determined by a change in color - it can vary from white to brown. After some time, the weevil beetle larva turns into a pupa. The legs, the rudiments of a head with a proboscis and wings will be clearly visible on it.
Gray bud weevil
Appearance
This pink-gray beetle reaches 6.5 millimeters in size. The proboscis and head are quite short. The elytra is convex, and the wings are not developed. The larvae of this beetle are white in color with a beige head.
The beetle overwinters directly in the ground and comes out only at the very end of March. The beetles almost immediately find fruit trees and crawl towards their crown. At first they feed on the buds, and then on the leaves and buds. As a result, the foliage deteriorates greatly, and the buds remain without interior.
Reproduction of these small weevils begins in early May. Female insects lay from twenty to forty eggs on the foliage of a tree in one clutch. After a few weeks, the larvae mature, which immediately fall to the ground and become buried almost half a meter deep. Their further development takes place there, because the main food of the larvae is tree roots. In the rhizomes of fruit trees they survive the cold season, and in August of the following year the larvae pupate.
By September, full-fledged adult individuals appear, which also overwinter in the ground and emerge only in the spring. Thus, the growing season of these pests lasts two years.
Harm
The beetle easily destroys the flowers of trees such as cherries, apricots, sweet cherries, apple trees, as well as plums and pears. Mass reproduction of this bug leads to partial damage or complete destruction of the entire green mass of the fruit tree. Weevils eat away pistils and stamens, so flowers and young tree buds suffer greatly.
The harmful activity of this small beetle leads to the complete death of seedlings, so this beetle can cause great harm to forestry and gardening.
What does an elephant eat?
The insect is not selective in food; it consumes leaves, stems, and eats the fruits and roots of the plant. Depending on what the elephant beetle eats, entomologists divide insects into the following groups:
- Monophages are pests that consume strictly one type of plant.
- Oligophages are beetles that feed on garden crops that are similar in appearance.
- Polyphages are omnivores that destroy any vegetation in their path.
These features mainly determine the habitats of weevils.
Some representatives of the species can be beneficial to humans. We are talking about mass destruction of weeds. Such insects are widespread in Brazil and Australia. Several types of useful mowers were brought to Russian territory, where to this day they continue to fight against salvinia, which pollutes water bodies.
Nutrition and lifestyle
Elephant beetles appear between September and December. They fly well and are able to travel long distances in search of food, although they prefer to move on the ground and tree trunks. The main activity is at dusk and at night, although sometimes beetles eating food can be seen during the day. But still, more often in the daytime they rest, hiding among the branches and leaves of trees.
Insects feed on the sap of leguminous and rutaceous trees, for which they gnaw the bark with their jaws and drink the secreted sap. They also enjoy eating ripe pineapples, bananas and other tropical fruits. In captivity, an animal can eat one avocado or other fruit of a similar size per day. Interestingly, in the event of a cold snap, beetles can maintain their own body temperature at the desired level, like warm-blooded animals.
Main varieties of elephants
It is impossible to describe all the larvae of weevil beetles and adult individuals living in the territory due to their countless numbers. Below is a brief description of the most common types.
Barn weevil. A small representative of the species with underdeveloped wings. It has spread around the world with grain crops, which it actively eats, thereby posing a danger to the contents of barns. Females make holes in grains of cereals or legumes and lay up to 300 eggs at a time. Damage to the crop is caused by both adults and larvae. Due to the extensive extent of the damage, grain after a weevil invasion is not suitable for food. The barn elephant beetle has several subspecies: rice, corn, and rice broad-proboscis.
Nodule striped weevil. The length of an adult pest reaches 5 millimeters. Affects legumes. The larvae destroy the root system, and mature insects eat the leaves and stems. During the season, the female of the species lays a record number of eggs - up to 3 thousand!
Beet mower. A large beetle with a short trunk. The body is lined with thick ash-gray scales. How dangerous are elephant beetles of this species? They destroy the sugar beet crop. The pest appears on agricultural land in early spring and feeds on weeds before beets germinate. Sexually mature individuals eat young shoots of the sweet crop. The larvae damage the root. As a result, the quality indicators of beets are sharply reduced.
The weevil is a fruit pest. It poses a particular danger to fruit trees, destroying all their parts, from the ovary and young shoots to flowers, bark and wood. The most widespread are vetch, Crimean, cherry, black and other types of garden pests.
Acorn elephant beetle. It is distinguished from its relatives by an elongated thin proboscis, the dimensions of which are equal to the dimensions of the body. The nose ends with strong jaws that turn into a drilling apparatus. Females lay eggs in oak acorns that have reached maturity. Drilling a hole in the fruit sufficient to create a clutch takes up to 8 hours for a female individual. The inside of an acorn is a favorable environment for the growth and development of larvae, which feed on its juicy pulp. Upon reaching maturity, the insects gnaw through the outer shell of the fruit and burrow deep into the soil. In the spring, pupation occurs.
Berry weevil. Destroys harvests of raspberries, strawberries, strawberries, blackberries, grapes and other sweet crops. The most common pest of this group in Russia is called the earthen elephant. It hibernates in winter and parasitizes plant bushes in the spring.
Buckwheat or Ussuri mower. Destroys crops and valuable crops. Adult representatives of the species cause damage to mature kernels, while the larvae eat stems and foliage.
To begin the fight against the weevil and protect the crop from destruction or damage, it is necessary to become more familiar with its development, feeding method and reproduction characteristics.
Five-spotted weevil
Appearance
The length of an adult five-spot weevil is four millimeters. It has a white belly, a red pronotum, and two spots on the elytra. The curved beetle larva grows up to 7 millimeters and is yellow in color with a brown head. The five-spotted weevil spends the winter under the remains of various plants and climbs to the surface in early May. With the appearance of the very first bean shoots, the pests migrate and then feed on the early shoots of various beans, peas, and field radishes.
Until the beginning of June, these beetles “occupy” all bean fields. At this time, reproduction and egg laying occurs. The latter, after gnawing through the shell of the bean, is deposited inside the seed.
A week later, the already mature harmful larva gnaws away the tasty bean contents for a month. During this time, the entire development of the small beetle larva is completed, and it falls out of the pod onto the ground and begins to pupate.
Adults of the five-spotted beetle are born around August. They spend the winter in the soil until spring.
Harm
This type of weevil can be found in many regions of Russia. It damages a variety of legumes - peas, china, lentils. What is the harmfulness of an adult? The beetle gnaws holes up to five millimeters in the leaves and stems. The larvae of the five-spotted weevil gnaw away the tasty contents of the grain. As a result, the plant simply dies. After all, the beans become deformed and immediately stop in their development.
To effectively protect this pest, the following methods are currently used:
- Early plowing of agricultural fields.
- Treatment of all seedlings with special insecticides.
- Spatial isolation of all lentil and pea plantings from the wintering site of five-spotted bugs.
Basic methods of dealing with elephants
Agronomists and gardeners starting to grow crops must take a set of measures to destroy and prevent the appearance of weevils. It is also necessary to get rid of pests at the household level.
Large agricultural companies practice the following methods of combating elephant beetles:
- Deep plowing and loosening of the soil in the spring-autumn period is a real opportunity to destroy eggs laid in the ground or larvae preparing for wintering.
- Infected plants are removed and burned.
- Practice rational crop rotation.
- Application of modern insecticides.
The measures described above to combat weevils in combination will ensure a significant reduction in the number of insects in the fields and in storage facilities.
Prevention measures
Of course, prevention will not provide a complete guarantee that beetles will not appear on the site. But the number of weevils can be significantly reduced if you follow simple rules.
- follow agricultural practices and care rules;
Weevil beetle.
- choose your neighbors correctly;
- carry out pruning and digging, plowing in the fields;
- remove carrion and litter;
- feed and monitor the health of the plant in a timely manner;
- carry out preventive spring spraying.
Mower in residential premises
The weevil in an apartment or private house is a common phenomenon. In a human home it is always warm, cozy, and there is something to eat. This is the most favorable environment for reproduction. In order not to say goodbye to stocks of grain and cereals, owners of apartments and houses must respond in a timely manner to the appearance of unwanted guests and systematically carry out preventive measures in order to prevent their return.
First of all, all cereal stocks must be sorted out, the flour sifted, and any pests found must be collected and destroyed. An effective way to disinfect damaged cereals is by frying or freezing. The described method also has its drawbacks: after prolonged exposure to extreme temperatures, the room will have to be thoroughly cleaned.
Traditional methods of fighting weevils
Insects with a long trunk do not tolerate ash, mustard, ammonia and laundry soap. Solutions with one of the above components, evenly sprayed over the surface of the plantings, if not completely get rid of the invasion, will significantly reduce the number of pests.
No less effective are infusions of tansy, wormwood and capsicum.
When folk remedies fail, homeowners resort to using chemicals. To prevent fruit poisoning, processing must be carried out in strict accordance with the instructions. The following drugs are popular today: karbofos, Inta Vir, Actellik, Antonem-E, Nemabakt, etc.
Rational application of the pest control methods described above will allow you to get rid of it for a long time and protect the crop.
Types of plant pests
Some representatives of weevils can consume only one type of plant or representatives of one family, but there are also completely unpretentious polyphages.
Acorn
The fruiting oak beetle is a small brown-red beetle with a long trunk and a body covered with scales. Flight occurs throughout the summer. The beetle affects all parts of oak, birch and linden.
Strawberry
The flower beetle on strawberries and wild strawberries spoils the roots, buds, stems and fruits. The fight against them is carried out very carefully in order to preserve the harvest and not spoil it.
Apple
A small beetle, inconspicuous, but very malicious. It affects the buds of garden crops: apple trees, pears, hawthorn. Doesn't disdain berries either. Reproduces quickly.
Raspberry-strawberry
Pest of rose flowers and all berry crops. They eat holes in the leaves, eat buds, and the larvae can damage the roots. Epidemics often occur when landing close together.
Beetroot
The pest is a monophage and is very widespread, but it does not change its preferences. They gnaw on young leaves; if there are not enough beets, they switch to weeds.
Klubenkovy
Affects legumes, alfalfa, lupine, china, astragalus, clover. There are many beetles of this species, the most dangerous ones are striped and bristly.
Pine
It can be big or smaller. A beetle with a long proboscis and an excellent appetite. The larvae eat only the roots of coniferous trees, while the adults eat all sorts of deciduous trees.
