It resembles the known European hybrid
between a species of the section Vetrix ( S. caprea or S. cinerea ) and S. viminalis . This hybrid was recorded
from SE Massachusetts under the name S. x smithiana . The characters of this tree, however,
don't completely match S. x smithiana . Alternatively this could be a spontaneous
hybrid between the only two willows common in the Forest: the native
S. occidentalis ( S. tristis ) and introduced invasive S. atrocinerea . To test this hypothesis, one should either try to
obtain an artificial cross between the two willows and compare it with the
willow in question or apply molecular methods.