1 F. pennsylvanica var. lanceolata (Borkh.) Sarg. (syn. var. subintegerrima (Vahl) Fern. was combined with F. pennsylvanica Marshall. 2 F. excelsior var.aurea was combined with F. excelsior L. 3F. rhynchophylla Hance and F. chinensis rhynchophylla(=F. chinensis Roxb. subsp. rhynchophylla (Hance) A. E. Murray) were combined with F. chinensis Roxb. 4 The sample size was too small to be included in one-way ANOVA. 5Canopy index: 1 = over 80% live crown; 2 = 60%-79%; 3 = 40%-59%; 4 = 20%-39%; 5 = below 20%. 6 bark splits: 0 = absent; 1 = present; 5-7. Means within a column followed by different lowercase letters are significantly different (Tukey test, α=0.05).