Content
Leaf roller on an apple tree is a fairly common occurrence. To prevent this pest from causing a lack of harvest, urgent measures must be taken as soon as characteristic signs of damage appear. Therefore, you should know what the leaf roller looks like, what can trigger its appearance, basic control methods and preventive measures.
Leaf rollers are nocturnal
What does a leaf roller look like on an apple tree?
This pest is a small-sized butterfly, the wingspan of which does not exceed 2.5 cm. The leaf roller belongs to the Lepidoptera family. In appearance it is similar to a moth or moth. The body is thickened, densely covered with hairs, gray in color.
A characteristic feature of the leaf roller is its triangular or trapezoidal wings. The pattern on them may consist of oblique, transverse stripes, depending on the variety. In a calm state, the leaf roller's wings are folded horizontally, completely covering its body, and not vertically, like most butterflies.
The caterpillar larvae of this apple tree pest are almost naked, with sparse short hairs.Their body length reaches 1-2 cm. They have eight pairs of legs, yellowish-green color with a black or brown head.
What harm does
Female leaf rollers are very fertile. After emerging from the pupae on the third day, they begin to mate and after a few hours lay eggs between the leaves, on young shoots, in the forks of branches, ovaries, and inflorescences of the apple tree.
It is the voracious larvae of the pest that cause serious damage to the tree. Until the moment of pupation, they constantly eat in order to fully develop. The first generation of offspring damages the flower buds, which leads to a decrease in the ovary. After this, the leaf roller caterpillars move to young foliage and eat the tops of the shoots. This leads to a delay in the development of the tree. In the second half of summer, a new generation of pests can be found on fruits in which they eat holes.
Leaf roller larvae can cause the greatest harm to young apple tree seedlings, since the process of photosynthesis is disrupted in damaged leaves. And this significantly weakens the tree and can lead to freezing in winter.
The leaf roller may also appear when purchasing an infected seedling.
Signs of defeat
The sooner a leaf roller can be detected on an apple tree, the less damage it will cause. The lesion can be identified by characteristic signs. But depending on the period of the year they may differ.
Main features:
- During flowering and leaf opening, cobwebs appear on the buds and tops of young shoots, eaten petals, and plates.
- At the end of spring, the first ten days of June, you can see curled leaves.And cocoons appear on the veins.
- In the second half of summer, young branches are entwined with a thick white web with a silvery tint. The active years of adults begin.
- In early September, when examining the plates, oviposition can be detected. They are covered with a damp coating.
- In mid-autumn, many twisted leaves appear on the affected apple tree, covered with a thick web in which the pest’s overwintering cocoons are located.
Reasons for appearance
Insufficient and improper tree care can provoke the appearance of leaf rollers on apple trees. Since this leads to a decrease in their resistance to adverse external factors.
Main reasons:
- lack of fertilizing;
- untimely use of nitrogen fertilizers;
- crown density;
- failure to carry out preventive treatments.
The pest attacks not only apple trees in the garden, but also pears, rowan and cherries. And the close placement of such trees contributes to its massive spread in the garden.
Measures to combat leaf rollers on apple trees
To get rid of the leaf roller on an apple tree and prevent its mass reproduction, comprehensive control measures should be used. To do this, you can use chemicals, folk remedies, as well as mechanical and biological methods. In this case, it is necessary to treat not only the infected apple tree, but also all fruit and berry crops that grow nearby.
Chemical preparations for leaf rollers on apple trees
This method of control helps to quickly reduce the number of pests. But it cannot be used during the flowering and harvesting period. It should also be borne in mind that a one-time treatment will not be enough. Since the destructive effect of insecticides does not apply to oviposition.
It is recommended to spray apple trees against leaf rollers with the following preparations:
Coragen Expert Garden. A systemic drug against a complex of pests, including helping to get rid of leaf rollers on apple trees. The active ingredient is chlorantraniliprole. To spray an apple tree against leaf rollers, dissolve 4 ml of the drug in 10 liters of water.
- Fufanon. The drug has contact-intestinal and fumigation effects. When processing, it is necessary to apply the solution evenly to the leaves, trunk and branches of the apple tree. The active ingredient is malathion at a concentration of 570 g per liter. Visible results are already visible within a day. To spray an apple tree, you need to dilute 10 ml of the drug in a bucket of water.
The waiting period after using Fufanon is three weeks
- Dursban. An insecto-acaricide that is effective not only against leaf rollers, but also against ticks. Resistant to being washed off by rain two hours after treatment. The active ingredient is chlorpyrifos at a concentration of 480 g per liter. To spray an apple tree, you need to dissolve 8-15 ml of the drug in a bucket, depending on the degree of infection.
The protective effect of Dursban lasts for two weeks
- Chord. A systemic insecticide belonging to the category of pyrethroids. The active ingredient is alpha-cypermethrin. Its content in the product reaches 100 g per liter. After spraying, the active component quickly penetrates the leaves and spreads through the vascular system to all parts of the tree. The duration of the protective effect can be up to four weeks. To process, you need to dissolve 3 ml of the product in 10 liters of water.
Accord begins to act three hours after spraying
It is recommended to treat apple trees against leaf rollers with chemicals at the stage of bud break and after flowering, as well as in the fall after the fruit is harvested. However, medications should be alternated to prevent pests from becoming addicted.
Folk remedies for leaf rollers on apple trees
You can treat apple trees against leaf rollers in the spring and during the season using folk remedies. They are especially relevant during the period of ovary formation and fruit ripening, when the use of chemicals is unacceptable. However, it should be understood that folk remedies are unable to cope with the massive spread of the pest. They help solve the problem at the initial stage of the lesion and as a preventive measure.
Effective folk remedies:
- Sagebrush. To combat the pest, you need to prepare a special decoction. You will need to chop the above-ground part of the plant and add warm water and leave for a day. When using fresh herbs, the ratio should be 1:1, and for dry wormwood 1:3. After the waiting period, simmer the mixture over low heat for half an hour. Then it needs to be cooled and strained. Before spraying, the concentrate should be diluted with water in a ratio of 1:2.
- Tobacco. To get rid of the misfortune, you need to pour 500 g of the component into 10 liters of hot water and mix. The mixture should be left for 72 hours and then strained through cheesecloth. Before processing, the resulting product must be diluted with water 1:1 and pour 40 ml of liquid soap into it and mix.
- Tomato tops. To combat the leaf roller, you need to finely chop the shoots, leaves and roots of tomatoes and add warm water in a 1:1 ratio. The resulting mixture should be left for a day and then boiled for 30 minutes.After cooling, strain the product and add the same volume of water before spraying.
Folk remedies have a repellent effect on the leaf roller
Mechanical method
It is also recommended to combat the pest using special traps. This allows you to significantly reduce the number of sexually mature females.
To do this, in the garden you need to hang a plastic container with the neck cut off on the branches of trees, into which you need to pour kvass, fermented jam, and beer. However, traps must be used at night so that they do not attract the attention of pollinating insects.
Biological method
It is recommended to combat leaf rollers on apple trees after flowering and during fruit formation using biological preparations. They have a gentle toxic effect and have a short waiting period.
Among them:
- Fitoverm;
Fitoverm has an insecticidal and acaricidal effect
- Lepidocide;
Lepidocide is safe for humans and warm-blooded animals
- Guapsin.
Guapsin can be combined with fungicides and growth promoters in one tank mix
Prevention
To prevent the massive spread of leaf rollers not only on the apple tree, but also in the garden, it is necessary to adhere to simple preventive measures. However, their effectiveness directly depends on the regularity of their implementation.
Prevention measures:
- feed trees in a timely manner, taking into account their stage of development;
- remove fallen leaves;
- carry out whitewashing of trunks and skeletal branches before the beginning of the growing season and at its end;
- spray the crown with insecticides several times a season;
- treat newly acquired seedlings with preparations;
- pluck curled leaves and burn them;
- In the fall, clean trunks and branches from exfoliated areas of bark and moss.
Conclusion
The leaf roller on an apple tree not only leads to a decrease in yield, but can also cause the death of young seedlings. However, it is not difficult to prevent the massive spread of this pest if you regularly inspect the leaves and shoots of trees, and also take timely measures to destroy the larvae at the initial stage of the attack.
