"The aspen has been called a very poetical tree, because it is the only one whose leaves tremble when the wind is apparently calm. It is said, however, to suggest fickleness and caprice, levity and irresolution--a bad character for any tree. The small American aspen, which is quite common, has a smooth, pale-green bark, which gets whitish and rough as the tree grows old. The foliage is thin, but a single leaf will be found, when examined, uncommonly beautiful. A spray of the small aspen, when in leaf, is very light and airy-looking, and the leaves produce a constant rustling sound. 'Legends of no ordinary interest linger around this tree. Ask the Italian peasant who pastures his sheep beside a grove of _Abele_ why the leaves of these trees are always trembling in even the hottest weather when not a breeze is stirring, and he will tell you that the wood of the trembling-poplar formed the cross on which our Saviour suffered.'"