The leaves of Salix babylonica are simple, alternate and the margins are toothed. The youngest branches tend to be long and pendulus, being the source of the name "weeping willow". It has the potential to become a large tree. Among the simple, alternate-leaved trees, the genus Salix shares the unique character of a single visible outer bud scale, making the willows as a group relatively easy to recognize. In addition to the 7 species of willow trees listed in this web page there are 17 species of willow shrubs in Wisconsin. The willow species are difficult to distinguish and any "shortcuts" around the proven keys are likely to result in frequent errors. See the key to willows for helpful characters to identify the species, or try the more thorough keys in Michigan Flora vol 2.

Salix babylonica is an alien species in Wisconsin. It is widely planted, and seldom or never escapes, but people are fond of planting it in wet areas along lakes and streams where its origin may be difficult to determine. It does not appear to be invasive.