Firethorn is one of the relatively hardy garden shrubs. With a good choice of location and not too moist soil, it thrives healthy and strong. Some varieties may develop scabs. Therefore, choose a species in advance that is robust against this fungus.
fungal attack by scab
In humid weather conditions, the mycosis can spread like an epidemic. The fungal spores overwinter both in the fruit and in the bark and fallen leaves of firethorn. In the spring, the young leaves and fresh shoots are infected first. As soon as firethorn fruit forms, these also show the typical damage pattern.
The bad image
The berries turn an unsightly brown or gray color and have a cracked, scaly surface. The leaves show the typical grey-brown fungal growth. The mycelium of the fungus runs through the entire leaf and parts of the bark.
The fight
Due to the long period of infection, combating scab is difficult. It is usually impossible to pick off all the affected leaves and flowers. Therefore, cut back all affected branches deep into the healthy wood. Since the fungal spores also survive in the compost, you must dispose of the removed plant parts in the household waste. To ensure that the fungus is not transferred to other garden plants, you must then meticulously disinfect the cutting tool.
Spraying with pesticides, on the other hand, is not very promising.
When pruning, make sure that the trees are loose and permeable to air. This allows dripping water after rain showers to evaporate quickly and minimizes the risk of infection.
Fire blight infection
Fire blight is increasingly spreading in some regions of Germany. Provided they have good living conditions, it is impossible to permanently keep the bacteria away from the affected areas. Fire blight spreads quickly over large areas and damages not only firethorn but also numerous fruit trees. Because of its danger, this plant disease is notifiable.
The bad image
In spring, firethorn flowers and leaves wither and turn brown-black; they look burnt. The tips of the shoots typically curve downward. An initially colorless, later yellow-brown bacterial mucus emerges at the infection sites of the shoots. In winter, dead spots appear on the trunks and branches of the affected plants, resembling canker sores.
The fight
There is no effective pesticide against fire blight. In order to prevent the disease from spreading, the affected trees must be precisely cut out or cleared and destroyed by a specialist. The experts at the responsible plant protection office will provide information on suitable measures.