Leaf turgor loss point at full hydration for 41 native and introduced tree and shrub species from Central Europe

The last years, Central European forests have suffered from drought as a direct consequence of climate change. All these forests have a long management history and it lies in the landowner’s responsibility to replant damaged forests. Hence, landowners and the government are searching currently for species suitable to replant in areas affected by tree die-offs. It is a matter of fact that good knowledge of drought resistance of species is a critical measure for the current replanting efforts. We determined a widely recognized trait for leaf drought tolerance (leaf water potential at turgor loss point at full hydration, πtlp) in 41 woody species native or introduced in Central Europe. The osmometric rapid assessment method was used to measure the leaf osmotic potential at full hydration (πosm) of sun-exposed leaves and converted to πtlp. Mean πtlp of the native species was −2.33 ± 0.33 MPa. The less negative πtlp was found in the introduced species Aesculus hypocastania and was at −1.70 ± 0.11 MPa. The most negative πtlp, and thus the potentially highest drought tolerance, were found in the introduced species Pseudotsuga menzesii and was at −3.02 ± 0.14 MPa. High or less negative πtlp is associated with lower drought tolerance, whereas low or more negative πtlp stands for higher resistance to drought stress. For example, the two native species Illex aquifolium and Alnus glustinosa are species naturally associated with moist habitats and are characterized by the least negative πtlp of −1.75 ± 0.02 and −1.76 ± 0.03 MPa, respectively.