As with the majority of native trees, there are also pests that cause problems for the birch. In addition to the very common fungal infestation, to which birch trees are relatively susceptible, various creatures feast on the trees. You can find out which ones don't cause any harm and when you should intervene here.
Which pests often occur on birch trees and how can you combat them?
Common pests on birch trees include birch leaf rollers, large birch sawflies, thrips, aphids and birch bugs. Collection strategies include removing infected leaves, pesticides and preventive measures such as fine-mesh window nets.
Pests in the birch tree – these are the most common
Birch trees can be affected by a wide variety of parasites. In German-speaking countries these are mainly the following species.
Birch leaf roller
As its name suggests, the birch leaf roller causes curled leaves. These just hang brown and dead on the birch trees and some other types of trees. It is a three to five millimeter large beetle with a punctured elytra. Usually no major damage is caused. You can prevent the annoying sight by removing an affected birch leaf as quickly as possible. Removing the leaf wraps will reduce infestation next year.
Great Birch Sawfly
The birch sawfly caterpillars, which are approximately 25 millimeters long, cause heavy damage to the edges of the leaves. This can extend to trees that are completely bare. However, the damage is generally limited and does not require any countermeasures. It may be advisable to remove leaves that are heavily covered with caterpillars.
Thrips
Silvery, speckled leaves are usually an indication that so-called thrips or fringed winged beetles have attached themselves to the birch tree. However, if it is not a life-threatening, high-level invasion, you do not need to intervene. If necessary, the tree regulates the problem itself by shedding affected leaves prematurely.
Various types of aphids
What is recommended for thrips also applies in the case of aphids: observe the tree and only use pesticides if there is a severe infestation. Lavender placed near the tree may help.
birch bug
If your birch tree is inhabited by brown animals about five millimeters small with black dots, they are probably birch bugs. They make themselves noticeable through their pronounced feeding behavior, but in principle do not harm the tree.
Rather, they become a nuisance for the garden owner, because the bugs multiply extremely quickly and like to get from the birch tree in the garden directly into the house. There they chirp annoyingly and cause an acrid smell. The only thing that helps here is prevention, ideally with fine-mesh window nets. You can spray pests that have already arrived in the house with lavender water and then carefully sweep them away.
