Abstract:After the girdled trunk of Eucommia ulmoides Oliv. was locally damaged usually no bark was regenerated at the injured area. However, abnormal structures were observed in the newly-formed bark in the adjacent region. Similar results also occurred in simulated experiments. After girdling, a strip about 10×2 cm2 and 1 mm in depth was scraped in the exposed area ensuring no bark regeneration in this artificially ruined area. Hence one month after the treatment it was seen that new vascular cambium developed in the regenerated bark around the destroyed area. However, the newly-formed bark above the harmed area was about two-fold thicker than that below the area. The differentiation of cambium and starch distribution were quite different on both sides.