The sycamore is usually a tree of floodplains, stream-sides and moist banks. Here, however, sycamores are growing on a ridge. This suggests that a water source seeps beneath this ridge and provides the sycamores with adequate moisture. To recognize a sycamore, look for a tree with white bark on the upper portions. Sycamore Ridge is a good example of an esker, a long ridge of gravel and other sediment, typically having a winding course, deposited by meltwater from a retreating glacier or ice sheet.