Fig. 2

Seedling total biomass of Amorpha fruticosa (a) and Robinia pseudoacacia (b) under different defoliation treatments. The values shown are mean ± SE (n = 4). Different letters indicate significant differences among different defoliation treatments (p < 0.05) with Duncan’s test. CK, no defoliation; TD, defoliation of the top down 50% of the crown; BU, defoliation of the bottom up 50% of the crown