All about sawflies

Sawflies pose a huge threat to future fruit crops. Insects are resistant to adverse natural conditions, and the only way to combat them is the use of insecticides. On the territory of Russia, there are about 2000 species of this pest. They harm not only horticultural crops, significantly reducing yields, but also forest plantations in the wild.

A small insect 5-7 mm long with two pairs of transparent wings. The sawfly belongs to the hymenoptera insects. Depending on the species, the color of the insect's body varies from light yellow to dark brown. Adults have a large head with two round large eyes on the sides and 3 simple ones in the center. Outwardly, some species look like flies or beetles, others are similar to bees or wasps.

The sawfly got its name due to the similarity of its ovipositor (an appendage at the tip of the body of an insect female, with the help of which she makes a hole in a plant shoot and lays eggs there) with a saw blade.

An adult insect does not feed, and its life is short-lived. The main purpose of an adult insect is reproduction. The female is able to lay eggs 3-4 times in one summer. Each clutch can contain up to 100 eggs. The female lays eggs in soft young shoots, making a small incision. She walled up the hole so that the eggs would not die.

After hatching, the larvae begin to actively devour foliage, shoots or fruits of shrubs and trees. Most often, the larvae are smooth, less often covered with fluff or hairs. The larvae of some species are covered with mucus with a specific odor. Compared to adults, they are larger in size (approximately 20-25 mm in length) and cause tremendous harm and damage to fruit crops. Sawfly larvae are real gluttons, after which only veins of foliage remain on the trees.

Larvae (larvae) develop for about a month. They were named false caterpillars because of the similarity with the caterpillars of ordinary harmless butterflies. You can distinguish a pest from a harmless caterpillar by the number of eyes and legs. The sawfly larva has 2 eyes, and the real caterpillar has 6. The larvae have 6 or more pairs of legs (some of which are false), and the caterpillars have less than 5. False caterpillars from the same clutch keep in groups on one plant. A month after hatching, the grown caterpillars descend to the ground, where the pupation process takes place. And already in the middle of summer, young individuals appear, ready to lay eggs. The cycle takes place until the end of autumn. Cocoons are most often hidden shallow in the upper layer of soil under a tree or shrub on which the caterpillar lived.

The first generation of larvae pupates, turns into adults. And by the middle of summer, it gives birth to a new generation of larvae, which continue to eat the castings and make tunnels inside the trunks. This worship manages to pupate by autumn, cocoons survive the winter under a layer of soil and fallen leaves. And by the end of May, adults appear, ready to lay a new clutch of eggs. In favorable climatic conditions and sufficient food, the number of generations can increase to 4 in one season.

Irreparable damage to fruit crops is caused not by adults, but by larvae that feed on leaves, shoots or fruits, some species make tunnels in shoots and trunks... Pest larvae eat and destroy foliage in different ways, depending on the type of insect. Some leave holes behind, others leave only veins (leaves skeletonized). Some species weave webs, creating nests (large cocoons), others fold individual leaves into tubes, creating a refuge for themselves.

A small number of false caterpillars and minor damage to a tree or bush can be easily removed by cutting off the affected shoots. While more serious damage can harm a fertile crop, and sometimes even destroy an entire tree or shrub, leaving the grower without a crop.

For the most part, sawflies are common in the temperate climatic zone. But their species can be found all over the world, and some genera live in the cold, harsh climate of the north. The spread of a certain type of pest is associated with the spread of the fruit crop that it feeds on, since the larvae of a certain type or subspecies feed on the leaves and shoots of a certain plant. Some insects lay their eggs on deciduous trees, others only on conifers. Other species prefer horticultural fruit crops and lay eggs on currants, strawberries, and apple trees.

By the name of the sawfly species, it is easy to understand which plant it prefers to inhabit and eat, and it is just as easy to determine its habitat. Most insects of this species prefer deciduous trees and the temperate climate of the middle zone. But there are species that live in South America and Australia, in places with a hotter climate.

Scientists have more than 6,000 species of this pest.... The species and subspecies of insects are distinguished depending on the habitat and food preferences. The most common and numerous types of this pest: apple, cherry slimy beetle, sawfly on roses, bread, red-headed, plum, mace, barberry and many others.

A little more than 2000 species of this pest are found on the territory of Russia. They cause great harm not only to garden plots with fruit crops, but also to forest plantations.

One rape sawfly larva can destroy more than 70-80% of the harvest of cabbage, radish or rapeseed. Plants damaged by larvae are not able to set fruits, gardeners are left without a crop. Yellow adults lay eggs in green plant shoots.

Gooseberry view lays eggs on gooseberry and currant bushes. Larvae can kill a large bush by eating foliage and young shoots. After the invasion of larvae, the bush is not able to withstand frosts and dies in the winter.

If pest larvae appear in the stems of the rose, the bush begins to dry out and wither. The insect of this species settles not only on roses, but also on strawberries and raspberries. You can check for the presence of pest larvae by cutting off one shoot.

In adults of the birch sawfly, the abdomen is orange or reddish-orange with tints, the wings are completely transparent, with black markings. The adult reaches 2.5 mm in length. The first larvae appear in May - early June, with the first really warm days and nights. The larvae are light green or light green with a dark stripe along the entire body. Caterpillars feed exclusively on birch foliage, leaving only veins from leaves.

The very small spruce sawfly larvae (only 1.5 mm in length) cause significant damage to all types of conifers. They are able to completely destroy young soft needles, which is why the tree stops developing and growing.

The star weaver lays the larvae on the pines. Its caterpillars entwine young needles with cobwebs and eat needles. Larvae can destroy up to 45% of needles on one pine tree.

Adults of the ash sawfly look like regular flies, their body is completely black, apart from the yellowish spots on the sides of the abdomen. This species is common in the ash forests of the European part of Russia and central Europe. Adult larvae are quite voracious, they can eat leaves entirely, leaving only a solid central vein. A distinctive feature of this species is the ability of females to self-fertilize.

In the fight against pests and hordes of their larvae, both special means and folk help gardeners. It is good to carry out preventive measures in the spring before planting seeds and in the fall after harvest. In the fight against pests, the main thing is not to miss the moment. As soon as you have seen adult insects, have noticed eggs or caterpillars, you need to start fighting them. If you miss precious time, it will be very difficult to get rid of pests, there are great chances to lose most of the crop. The affected bushes must be removed, and the remaining shoots must be treated with insecticides, or with a decoction of tobacco or wormwood.

One of the most popular means is spraying affected fruit crops. Treatment of infected plants with poisonous drugs is carried out in two stages. First, the plants are sprayed at the end of May, when the first leaves and young shoots have already appeared. The procedure is repeated 14-16 days after the first, usually in June. But you need to be in time before flowering. During flowering and fruit formation, it is strictly forbidden to treat plants with chemicals.

Spraying can be repeated towards the end of summer, when the fruits have already formed. This must be done in order to destroy the second generation of pests and prevent insects from spreading throughout the garden. It is necessary to carry out the treatment with poisonous substances not only of the tree itself, but also of the trunk circles, where the sawfly cocoons are hidden.

Shoots and ovaries affected by sawfly larvae must be cut off. It is best to burn the cut parts to avoid the spread of the pest throughout the site. For tall trees (for example, an apple tree), it is recommended to use trapping belts or special glue. The larvae will not be able to develop, pupate and lay new clutches.

It is recommended to regularly dig the soil around the trees (conifers and deciduous), where the larvae hide for pupation... Digging up near-trunk circles, you can easily find nests with larvae or cocoons. They must be burned, and the place of detection must be treated with insecticides.

Of the specially developed drugs against the sawfly and its larvae, such as Karbofos, Chlorofos, Kemifos, Fufanon, Benzophosphate, Aktara, Mospilan and other poisons from this category. When choosing an insecticide, you need to be sure that the larvae that appear on the plants belong to the sawfly. And, based on this, a remedy is selected against the pest. Note that some insecticides are useless when killing the sawfly.

Some gardeners (opponents of chemical weapons against pests) advise planting odorous, fragrant plants in areas to attract natural enemies of the sawfly and its caterpillars, such as lacewing, soft beetle or trichogramma.

With few pests, natural remedies can be used., for example, infusions of tobacco or wormwood, wood ash or garlic. Every seasoned gardener has his own tried and true recipe. But such infusions and solutions are more suitable for preventive measures than in a real fight against a pest.

As folk remedies to protect against the sawfly, gardeners recommend sprinkling trees and shrubs with various herbal infusions. Infusions of chamomile, wormwood or needles need to be infused for 2-3 days, then the concentrated infusion is diluted with running water, 1-2 tablespoons of soda can be added. Garlic infusion can be used immediately after preparation. But such spraying is suitable for plants where there are relatively few larvae. After spraying, the affected branches and fruits will still have to be removed.

From preventive measures, gardeners distinguish:

• regular weeding and loosening of the soil;

• removal and disposal of damaged shoots, leaves and fruits;

• shaking bushes and spraying;

• digging up the soil after harvesting.

For spraying, you can use soap solution (laundry or tar soap) or insecticide solution.

Never leave cut infected shoots, fruits and tree branches on the site. The larvae from them can move to healthy plants, or remain in the soil, from where adults will appear in the spring. And also some types of sawflies use old cut trees for wintering. It is best to immediately burn the affected shoots and branches of trees and found nests, this will prevent the sawfly from spreading throughout the site.