Fig. 5

Relationship between the irreversible diameter shrinkage DSirreversible during a temperature decrease to −25 °C measured in cold-hardy branches and hardiness rating that is based on the minimum temperature range in which the species prevail in the USA (P = 0.044; Dirr 2009). The highest cold hardiness is indicated with the smallest number in the rating system. Each species is denoted with the first letters of their scientific names: Carpinus betulus (Cb), Crataegus monogyna (Cm), Ginkgo biloba (Gb), Pterocarya fraxinifolia (Pf), Quercus palustris (Qp), Malus baccata (Mb), and Sorbus aucuparia (Sa)