Washington, Norton said, was interested in planting hemlock trees on his property.

诺顿表示，华盛顿有意在庄园里种植一些铁杉。

A tree expert at Washington Park Arboretum, Shea Cope, said that you can see evidence of tree stress in maple and hemlock trees.

华盛顿公园植物园的树木专家谢伊·科普说，你可以在枫树和铁杉上看到树木受到压力的证据。