Gooseberry sawfly: photo, control and prevention measures

Gooseberry sawfly (lat. Nematus ribesii) is one of the most dangerous pests of gooseberry and currant bushes. If you do not fight the sawfly on the gooseberry, carrying out the recommended agrotechnical measures, then crop loss and plant death will be inevitable.

What does the gooseberry sawfly look like?

There are two types of pest: yellow gooseberry sawfly and pale-footed:

• Adults (adults) of the yellow sawfly are reddish-yellow;

  

• The second, pale-legged, type of dangerous beetle is black in color, interspersed with light spots on the body and legs. The length of insects is no more than 8 mm.

  

In the larval stage, sawflies resemble their relatives, but, unlike them, they have not 8, but 10 pairs of legs. Experts call gooseberry sawfly larvae caterpillars. The color of the larvae of the yellow sawfly is bluish-green, the insects are covered with black growths, similar to warts, which grow up to 18 mm in length. At the same time, in the black sawfly they are smaller, no more than 1 cm, green.

Larvae at the end of summer go into the ground under the bushes to a depth of 6-12 cm, where they pupate and winter safely. With the advent of spring, adult insects appear from the pupae, their active phase coincides with the beginning of the flowering of red or black currants.

During this period, young gooseberry leaves are just beginning to unfold, and sawfly females begin laying eggs, cutting small depressions along the main vein of the leaf. Each female lays up to 60 eggs on the underside of leaves.

In cuts – “pockets” sawfly larvae quickly appear and grow. First, they gnaw through small holes, and then completely destroy the leaf blade. Sawfly larvae have five growth stages, each lasting 20 to 25 days. Then the insects fall to the ground and pupate. This is the first, spring generation of the sawfly pest.

In total, during the summer in central Our Country, 3-4 generations of the sawfly manage to develop on the gooseberry. The last generation leaves for wintering, the cocoon of whose representatives is denser and darker than the summer one. Gooseberries need regular inspection of the leaves, since the fight against the sawfly should be started as early as possible.

What harm does the sawfly gooseberry

Yellow and pale-legged gooseberry sawflies literally gnaw on the leaves of gooseberries and currants, leaving only veins. They harm crops while in the larval phase. Particularly voracious and dangerous are the second – fourth generations, that is, summer representatives. It is not easy to remove the first layer of the parasite, but the fight against the second and third generation takes even more time and effort.

The first generation usually remains invisible to gardeners. The first leaves eaten dry up, never having time to grow, and there is no fight against the sawfly. However, the first generation, skipped and not destroyed, gives life to the second, which already causes much more harm to the gooseberries.

The second generation flies out before the berries ripen, in the middle of summer. It is the most numerous and causes the most significant damage. Sometimes the fight starts too late. Insects attack currants and then move on to gooseberries. For one or two weeks, the bushes may be left without leaves, which weakens the plants, reduces growth and winter hardiness.

Due to the defeat by the sawfly, small, prematurely falling berries are formed. A strong pest infestation reduces the productivity of the bushes in the current year and prevents the future crop from forming. Noticing signs of the sawfly’s presence, you must immediately begin the fight. The third and fourth generations are smaller and develop mainly on gooseberries.

Methods of dealing with the gooseberry sawfly

The harm from sawflies for gooseberry bushes can become enormous if you do not fight and let everything take its course. Bushes should be inspected regularly in order to take timely measures and prevent pests from multiplying. The gooseberry sawfly damages the gooseberry with foci and nests. The number of pests in different years is more or less.

If such insects are found in a summer cottage, it is urgent to take control measures. Moreover, if you know the enemy of currants and gooseberries “by sight” from the description and photo. The following year, a comprehensive struggle should begin in early spring. This will greatly reduce the subsequent summer hassle associated with the fight against the gooseberry sawfly.

Photo of the gooseberry sawfly:

How to deal with a sawfly on a gooseberry with folk remedies

Methods that have long been used by the people are very good at destroying sawfly larvae, and at the same time other pests. These are mainly infusions or decoctions. For their preparation, substances and plants that are harmless to humans are used.

Folk methods are good because they can be used at any time: during flowering, filling and ripening of berries. They do not kill beneficial insects, do not interfere with pollination. You can eat berries sprayed with folk remedies on the same day. They just need to be washed well.

In addition to the protective effect, many folk remedies are at the same time feeding gooseberries. Due to this, the immunity of plants increases, they grow better, become stronger and are less affected by pests.

You can repeat such treatments after 7-10 days, if necessary, you can do it more often. It is useful to alternate treatments with ash and herbal infusions. The main means used:

1. Infusion of tomato leaves. It is prepared at the end of flowering (for this, stepsons and lower leaves of tomatoes are taken): 1 kg of green mass is poured with boiling water and cooled. A solution of liquid laundry soap (50 ml) is added to the filtered solution for better adhesion. This amount of infusion is enough for 2 – 3 bushes. Treatments can be repeated several times during the summer, they also destroy aphids well.
2. Ash infusion. Obtained from wood ash. Take 1 kg of sifted ash per 10 liters of hot water, insist for three days. Leaves are treated with a filtered solution from the lower and upper sides.

   Currant and gooseberry bushes are also watered with the help of sprinkling. After watering, sprinkle wood ash over wet leaves.

3. Chamomile infusion. To prepare it, take 1 kg of medicinal chamomile plants, cut and pour hot water. After insisting for 10 – 12 hours, the infusion is filtered, diluted in half with water. Add soap and spray the bushes.
4. Infusion of bitter wormwood. A remedy is prepared from 1,2 kg of grass in 10 liters of water. After a three-day infusion, the infusion is filtered, 70 grams of baking soda are added and the plants are sprayed.
5. Infusion on needles. Pour 2 kg of coniferous branches into a bucket and fill it with water. Insist for 6 – 8 days in the dark and filter. This is a concentrated product, before use it is diluted with water three to five times.

How to destroy the sawfly on the gooseberry with chemicals

Chemical preparations should be used in the garden plot in critical cases, because part of the chemical gets into the berries.

During the period when buds appear on currants and gooseberries, karbofos is sprayed. To do this, take 75 g of powder per 10 liters of water.

Good help against pests that eat leaves, preparations “Iskra”, “Decis”, “Aktara”, “Confidor”, “Kinmiks”.

Chemicals can be processed in the evening and morning hours. At this time, the activity of beneficial entomophagous insects (ladybugs, hoverflies), which eat pest larvae, is reduced.

To prevent the plants from getting chemical burns, in dry weather they need to be watered before spraying.

Mechanical control measures for the gooseberry sawfly

Among the mechanical methods of controlling the gooseberry pest, the following have proven their effectiveness:

1. Before the buds open in the spring, the soil should be loosened shallowly under the currants and gooseberries, having previously scattered around each bush 2 cups of wood ash mixed with 1 tbsp. a spoonful of dry mustard and 1 tbsp. a spoonful of red ground pepper. Then you need to bring under the bushes, a film or roofing material, the edges of which should be covered with earth. This method helps to simultaneously fight the gooseberry moth: adults flying out of the pupae collide with an obstacle – a film and die under it.
2. Hilling is considered an effective way to destroy sawfly beetles flying out of the ground. To do this, you need to take the soil from the row spacing or humus. The trunk circle under the currants and gooseberries should be covered with a layer of soil clean from pests to a height of 10 cm: sawflies will not be able to get through such an obstacle.
3. Throughout the season, it is important to shake off the found larvae on a bedding film and destroy them. In addition, damaged berries in which the larva sits should be burned. For convenience, you can put a bucket of soapy water near a currant or gooseberry bush and throw insects into it.
4. In autumn, it will be useful to re-dig the soil under the bushes. This measure will help to destroy the larvae that have left for the winter.

Preventive measures

Each pest recognizes “its prey” by smell. Preventive methods for controlling the sawfly on gooseberries are aimed at repelling or “confusing” the parasite. So that insects do not smell the plant that is attractive to them, plants with sharp, interrupting aromas are planted around currants and gooseberries. In addition, you can place the source of the interrupting smell in a jar next to the bushes. Plants and substances that repel pests include:

• tansy;
• garlic;
• tomatoes;
• elderberry branches;
• tar;
• turpentine;
• Creolin.

Against the sawfly, traps with pheromones are an effective method: substances that, on the contrary, attract sawflies. Moving towards an attractive smell, the beetles get on an adhesive tape, from which they can no longer peel off.

Conclusion

It is necessary to fight the sawfly on the gooseberry promptly, paying attention in time to the first signs of the appearance of the pest – the first leaves of the shrub eaten by its larvae. After that, it is important to choose the appropriate control methods – folk or chemical plant protection products. The gooseberry sawfly is a very dangerous pest of currants and gooseberries, because of which the gardener can completely lose the berry crop.