The experts met in Ellerhoop in the Pinneberg district on Tuesday to share their findings. These include the first results of an EU- and state-funded project in Heide, Husum and Lübeck, which is testing 20 different tree species and varieties for their future viability. One is in the process of expanding the range of trees in cities for greater diversity and response potential, Wrede said. This is necessary because trees are needed for a wide variety of places that fit right in. “The location conditions and the tree species requirements must match, then it will work. That's what we're looking for.' Wrede is convinced that birches and hornbeams, often cited as losers among urban tree species, can be viable in the right location. There is no tree species that can survive without water. For example, St. John's wort tolerates heat well, but needs a lot of water to evaporate. "If it doesn't have water, its heat tolerance is over." (Ellerhoop (dpa / lno)