Although the locust tree is very robust, it can still happen that some pests bother it. But if you intervene in time, you can prevent worse things from happening.
The robinia, also called Robinia pseudoacacia, is one of the robust trees. Life-threatening diseases or life-threatening pest infestations rarely occur in he althy robinias.
However, robinia leaf miners, aphids or phloespora leaf spot disease often cause problems for the owner of the trees. Here you can find out how you can easily get these problems with your robinia under control again.
Common diseases and pests at a glance:
✢ Black Locust leaf miner
As the name suggests, the black locust leaf miner is a pest that specializes in black locust leaves for food. The leaf miner has only been present in Europe since 1983 and has no natural predators here.
➜ Recognize:
An infestation is easy to recognize by the characteristic damage pattern of a meandering feeding track in the leaves.
➜ Fight:
The caterpillars can simply be collected from the affected leaves. However, the measure is not really necessary, because despite the visual damage, the he alth of the robinia is not permanently impaired by the leaf miners.
✢ Phloespora leaf spot
Phloespora leaf spot is a relatively common disease of black locust that is caused by the fungus Phloeospora robiniae and occurs mainly after a rainy spring.
➜ Identify:
The damage appears as brown spots on the leaves, which reach a diameter of between half a centimeter and one centimetre. In the course of the year, the leaves often appear deformed and are torn at the edges. Phloespora leaf spot can also affect shoots or petioles.
➜ Fight:
The infestation is not immediately life threatening, but should be fought. First try to solve the problem manually: remove all diseased leaves in autumn and shorten the branches on which you have infected shootsdetermine. The use of fungicides is not advisable until the following spring when the same symptoms appear again.
✢ Aphids
An infestation of aphids is also quite common on robinia. If you recognize the pests early, it is often sufficient to spray the leaves with a hard jet of water. If that doesn't help, you can try soapy water. To do this, dissolve a tablespoon of curd soap in a liter of lukewarm water and spray the leaves regularly.
Oil-based pesticides, which suffocate the aphids, have also proven successful in practice. Alternatively, you can also settle beneficial insects such as hoverflies, lacewings or parasitic wasps on the robinia. However, there is always a risk that the beneficial insects will look for their food on plants other than the infested black locust.