Fig. 4

Stress-strain curve of plant roots (a) 1-year-old H. rhamnoides; (b) 4-year-old H. rhamnoides; (c) 10-year-old H. rhamnoides.

Stress-strain curve of plant roots (a) 1-year-old H. rhamnoides; (b) 4-year-old H. rhamnoides; (c) 10-year-old H. rhamnoides.