How To Protect Fruit Trees From Bark Beetles

2024 Author: Sebastian Paterson | [email protected]. Last modified: 2023-12-16 13:47

Do not let bark beetles into the garden

Bark beetle

As practice shows, bark beetles are dangerous pests that can not only infect fruit trees in areas, but also lead to their death. Based on personal experience and the experience of other summer residents and gardeners, I tried to remove frequently asked questions from the land owners and give them more specific recommendations.

The bark beetles include, first of all, wrinkled and apple bark beetles, often called sapwood, as well as unpaired bark beetles, which are found everywhere in our zone, and the first and the last affect all fruit crops. All bark beetles are small beetles with a short body reaching 4 mm, and the beetles themselves and their passages through which they got out of the tree can be seen. The larvae of beetles lead a hidden lifestyle, are white-colored, with a brown head, have no legs and are usually curved, and their size is almost 2 mm larger than beetles.

Both larvae and beetles feed on living tissues and sap of trees, making passages under the bark, in which the larvae hibernate and pupate. All of these bark beetles usually affect weakened or diseased trees with wounds, burns, cracks, cracks, frost cracks, etc. in the bark. The unpaired bark beetle quite often affects young trees, which are characterized by abundant sap flow.

To consider and determine the varieties of bark beetles, their size, color and the nature of the moves made after removing the bark in this place help. As a rule, wrinkled bark beetle has a smaller size - 2.5 mm, apple - about 3 mm, and unpaired 3.5-4 mm, and males are smaller than females.

The color of the wrinkled bark beetle is usually black-brown, apple and unpaired bark beetles are often red-brown. Females of wrinkled and unpaired bark beetles lay eggs directly in the course, and females of apple trees for this purpose grind a chamber between bark and wood, from which the uterine passages depart and lay eggs in their walls. Determinants of the species of bark beetle can also be the species of trees that they affect most often.

For example, wrinkled bark beetle usually prefers plums and cherries, apple also harms pear and bird cherry, and only unpaired has no preferences, affecting all breeds. Note that, contrary to literary sources, neither the peculiarities of development, nor the time of emergence of beetles can be the determinants of these bark beetles, since all of them develop only one generation, and the time of departure, depending on the weather, can stretch until the end of July.

Wrinkled bark beetle

It is pertinent to note that in recent years, scientists have revealed that bark beetles have a very fine sense of smell, which makes it possible not only to choose the desired tree species, but also to distinguish a weakened tree from a healthy one by smell.

Moreover, as soon as the tree becomes the prey of bark beetles, and the beetles, penetrating into it, begin to throw out the dust of the bark, it attracts more and more groups of beetles to the tree. The larvae of bark beetles, having rich food, quickly grow up, and in the abandoned course, mushroom embryos accumulate, serving as an additional supplement to food for new groups of beetles. It is noteworthy that the processes of destruction of wood in the garden are more rapid than in the forest, where the number of beetles and their larvae is noticeably limited by woodpeckers and other insectivorous birds.

Judging from my own experience, it is quite difficult to fight the invasion of the bark beetle garden. Therefore, first of all, it is necessary to take preventive measures against them, and in addition to general agricultural recommendations related to providing conditions for the best growth and development of fruit trees (fertilization, fertilizing, watering, pruning, etc.), which are known from the literature, the following is very effective:

- covering the wounds on trees with garden pitch to eliminate the possibility of beetles laying eggs;

- coating the boles with clay with casein glue (200 g per bucket) and adding Karbofos to the mixture (90 g per bucket) to prevent beetles from flying out from under the bark and introducing their females under the bark for laying eggs;

- whitewashing of boles in the pre-winter period with the "Protection" emulsion or water-based paint to protect trees from the formation of defects (frost holes, cracks, etc.), in which beetles lay their eggs.

Apple bark beetle

If you have taken all the above measures, and the pests still appeared in the garden, then fruit trees should be treated with insecticides before flowering. At the same time, one should not use the Kinmix, Rovikurt and Fury recommended by the literature, since they are not allowed for use in summer cottages and garden plots due to excessive toxicity according to the RF law "On the safe handling of pesticides and agrochemicals".

According to the experience of gardeners against sapwoods, it is most effective to use the biological products permitted by the mentioned law: Bitoxibacillin at a dose of 60 g per bucket of water or Lipidocide at a dose of 25 g per bucket of water. Against the unpaired bark beetle, it is more effective to spray the trunks and branches with Karbofos (100 g per bucket of water) or Intavir (1 tablet per bucket of water).

I think that today any summer resident or gardener has every opportunity to ensure that bark beetles do not appear in the garden and do not damage the crop.