Since 2020, a project on various tree species has been running together with the Humboldt Universität zu Berlin.
For this purpose, various climate trees and long-established urban tree species in the metropolitan regions of Hamburg and Berlin (street and park sites as well as plant container trials) are being applied with Trichoderma, in granule form, to strengthen vitality.
So far, surveys on vitality, the occurrence of virus-suspicious symptoms and sampling have been taken from the trees. The project will continue at least until 2024.
Overview of the trees treated with Trichoderma:
- 6 Fraxinus ornus (street trees of which 3 are infested with Emara virus)
- 7 Amelanchier (street trees including 4 powdery mildew-susceptible juneberry and 3 non powdery mildew-susceptible juneberry ‘Robin Hill’’)
- 15 Betula pendula (street trees on park-like central strip, two of which are clearly damaged)
- 4 Betula pendula (park trees, combination treatment of Trichoderma with the product “Waldleben”)
- 30 Populus tremula (container plants, 7-year-old)
- 30 Quercus robur (container plants, 4-year-old with naturally occurring powdery mildew infection pressure)
- 2 Betula (large container plants, 10-year-old, infected with a virus associated with birch leaf curling)
- 3 Sorbus aucuparia (large container plants, 25-year-old, infested with Emara virus)
- 2 Ulmus laevis (large container plants, 20-year-old, infested with Carla virus)