Pests and diseases endanger the medlar and cause the leaves to discolour. Responsible for these damage images are not only faulty maintenance measures.
If the medlar gets brown spots, a disease or pests can be behind it
These are causes:
- frost damage
- parasite infestation
- leaf tan
frost damage
In winter, photinas often get patchy leaf discoloration when the ground is frozen deep down and the winter sun that falls directly on it draws moisture from the leaves. In the frozen ground, the roots cannot absorb water, after which the leaves become stained.
parasite infestation
Aphids feed on the sap of plants. While sucking the sap from the leaf webs with their proboscis, they inject their saliva. This creates brown spots. The vine weevil eats the leaf mass, which first leads to discoloration of the leaves and finally to death.
leaf tan
The spores of various fungi attack the young leaves in windy and rainy weather and first cause a spotty whitening of the leaves. In severe infestations, the spots turn red, brown, or black and spread across the leaves.