Raspberry stem fly: control methods, spring, summer, photo

The raspberry fly is a dangerous pest that can cause not only the lack of a crop, but also the death of the entire raspberry. In order for the gardener to take timely measures to destroy it, you need to know the first signs of defeat. Because any delay only exacerbates the problem. And then it will take much more effort to eliminate it.

Raspberry stem fly lays up to 90 eggs per season

What does a raspberry fly look like

This is a small insect. The raspberry stem fly (Chortophila dentiens), as seen in the photo, resembles a midge in appearance. The length of her body does not exceed 7 mm. The color of the insect is gray-brown, the wings are transparent. The raspberry fly has three pairs of black paws.

Eggs are oval-oblong, light. Their size is 3 mm. The caterpillar larvae of the raspberry fly are off-white in color, without paws, move due to body contractions. Mouth apparatus gnawing type. The pupae of the raspberry fly are brown in color, their length is 5-7 mm. The cocoon is barrel-shaped.

Signs of damage to the bushes

A characteristic sign of raspberry damage by a stem fly is the withering tops of young shoots. Moreover, the loss of turgor occurs regardless of watering. Subsequently, the affected shoots acquire a bluish tint, the leaves on them begin to turn yellow from top to bottom, and then they dry out completely.

What harm does

In the spring, as soon as the soil warms up to +10 °C, sexually mature individuals of the raspberry fly appear from the pupae. Their active years begin at the end of April or May, depending on the climatic conditions of the region. After the mating season, female raspberry flies lay their eggs in the leaf axils on growing young shoots. After 8-9 days, small caterpillar larvae appear from them. They bite into the shoot and feed on its core. This leads to disruption of metabolic processes in tissues. As a result, the top of the shoot does not receive nutrition and begins to fade.

As the larva of the raspberry fly moves inside, the stem of the fruit bush turns black and dries out. As a result, the caterpillar of the raspberry fly reaches the base of the shoot and goes into the soil to pupate.

With the mass reproduction of the pest, most of the young growing shoots suffer, which leads to a significant decrease in yield this season in remontant raspberries and in the future in ordinary crops.

The pest initially attacks weakened plants

Causes of appearance

There are several provoking factors that contribute to the appearance of a stem fly in a raspberry.

Among them:

1. Close placement of plantings of blackberries, meadowsweet, meadowsweet. These crops are also susceptible to stem fly attack. And in the case of planting raspberries near them, sooner or later the raspberry fly moves to the neighboring area.
2. Aphid. Untimely control of this pest can lead to the appearance of a stem fly, as it is tempted by copper dew. Ants contribute to the mass spread of aphids in the garden. Therefore, the fight must be waged with them.
3. Lack of preventive treatments for bushes. In the spring, be sure to spray raspberries with insecticides during the period of bud swelling to prevent the appearance of pests.
4. Poor-quality humus, mulch. Pupated larvae can be found in organic fertilizer and peat. Using them, you can also bring a stem fly into the raspberries.

How to deal with raspberry fly in spring and autumn

If a raspberry is attacked by a stem fly, then urgent measures must be taken to save the fruit bush. To do this, you can use insecticides, biological preparations and folk remedies. Only complex control methods will help get rid of the pest and maintain high crop yields.

Insekticidы

Fighting the stem fly on raspberries should be done with special chemicals. They must be used for spraying shrubs during the growing season, as well as for watering to kill insect larvae and pupae.

When wilted tops appear, you need to cut them off, capturing a few sentiments of a healthy shoot, and burn them along with the larvae of the raspberry fly. And only after that carry out the treatment with insecticides.

The most effective means:

1. Karbofos. A highly toxic preparation that can be used once to treat raspberries during the period of active leaf growth, as well as spraying the soil at the base of the bushes. When using this tool, you must observe increased safety measures. Karbofos has a detrimental effect on bees. To prepare the working fluid, dilute 60 g of the product in 10 liters of water.
   
   

   Karbofos can be sprayed on raspberries at temperatures below 15 ° C

2. Spark. Broad-spectrum systemic insecticide. To control the raspberry fly in spring, it can be used to water shrubs to destroy pupae, and in summer when signs of damage appear. To prepare the working fluid, it is necessary to dissolve one tablet of the drug in 10 liters of water.
   
   

   Spark contains two active components, which increases its effectiveness

3. Actellik. A pyrethroid insecticide belonging to the organophosphorus group of drugs. The active ingredient is pirimiphos-methyl. Actellik has an insecticidal effect. The first results of the application become noticeable two hours after treatment. To prepare the working fluid against the raspberry fly, it is necessary to dissolve 2 ml of the drug in 2 liters of water.
   
   

   Actellik is effective against a complex of pests and also helps against ticks

4. Fufanon Nova. Universal insectoacaricide belonging to the class of organophosphorus compounds. The active ingredient is malathion, the concentration of which is 440 g per 1 liter. To prepare the working liquid against the raspberry fly, it is necessary to dissolve 10 ml of the product in 10 liters of water. It is recommended to spray berry bushes with Fufanon in the spring 2-3 weeks before flowering. The multiplicity of permissible treatments is not more than two.
   
   

   Fufanon Nova has a contact effect and has a fumigation effect

Biological preparations from the raspberry fly

You can also get rid of the raspberry fly with the help of biological preparations. They are characterized by a low level of toxicity and a short waiting time. Therefore, these raspberry fly control measures should be applied in June, when the berries begin to ripen. However, biological preparations are effective at temperatures not lower than +20 °C.

Valid biopreparations:

1. Fitoverm. This drug belongs to the category of insectoacaricidal, having a contact-intestinal effect. For the treatment of bushes against the raspberry fly, it is necessary to dissolve 2 ml of the drug in 1 liter of water. Spraying should be carried out in the evening or in the morning in dry calm weather.
   
   

   Fitoverm can not be used during the flowering period of raspberries

2. Aktofit. The drug is a clear liquid of a light or dark yellow hue with a specific odor. The active ingredient is aversectin. It provides safe protection for raspberries during ripening and picking. This bioinsecticide is not addictive and breaks down into safe components within two days after treatment. To prepare a working solution against the raspberry fly, dilute 4 ml of the concentrate in 1 liter of water.
   
   

   Aktofit does not harm the environment

Folk remedies

You need to start fighting the raspberry fly in early spring. During this period, the most relevant use of folk remedies. With their help, you can create unfavorable conditions for the transformation of pupae into sexually mature individuals. To do this, experienced gardeners recommend loosening the top layer of soil in the raspberries in the spring with the addition of mustard powder, wood ash or tobacco dust. All these components create an aggressive environment in the ground, which leads to the death of pupated larvae.

Also, birch tar can be used to scare away the raspberry stem fly from fruit bushes. To do this, add 10 g of this product to 10 liters of water and mix thoroughly. In order for the resulting solution to adhere well to the leaves, it is recommended to pour in an additional 30 ml of liquid soap. After that, spray the shrubs and the soil at their base against the raspberry fly. Repeat the procedure every week.

preventive measures

Proper and timely care of raspberries helps reduce the likelihood of stem flies in the garden. But preventive measures can give results only if they are carried out regularly.

To protect the raspberry from the pest you need:

1. Avoid dense plantings, thin out the growing young shoots.
2. Regularly feed the bushes, treat for diseases in order to maintain immunity at a high level.
3. Plant garlic, marigolds, coriander, celery next to raspberries. The smell of these plants repels the pest.
4. To combat the raspberry fly in the fall, it is necessary to remove plant residues in a timely manner and burn them. And you should also loosen the soil to a depth of 5 cm so that the raspberry fly pupae freeze out in winter.
5. In the spring, a mulch of humus or peat with a thickness of at least 8 cm should be laid at the base of the bushes. Not many flies can overcome such a barrier, trying to get out.
6. Spray raspberries with insecticides once a month at the beginning of the growing season to prevent infection.

Pest-resistant raspberry varieties

There are varieties of raspberries that are resistant to the raspberry stem fly. The more pubescent the shoots of the shrub, the lower the likelihood of pest damage.

Resistant varieties:

1. Vera;
   
   

   Vera – an early variety with small and medium purple berries

2. Zorenka Altai;
   
   

   Zorenka Altai – a large-fruited species, included in the State Register in 1990

3. Bell;
   
   

   Bluebell is suitable for cultivation in the central and northern regions

4. Reward;
   
   

   The tasting score of the Naprada variety is 4,5 points out of a possible five

5. Balm.
   
   

   Balm – in aroma and taste reminiscent of wild raspberries

Conclusion

The raspberry fly is a pest, the appearance of which is easier to prevent than to subsequently deal with it. Indeed, even a small number of these insects can significantly reduce the yield not only in the current, but also in subsequent seasons. And it will take a long time to restore the productivity of the raspberry.