Small flycatcher, extremely similar to several other species. Prefers shrubby open areas, especially around marshes. Western population prefers understory in riparian woods. Brownish above and pale below with barely any eyering. Wings dark with distinct white wingbars (brownish in Western population). Nearly identical to Alder Flycatcher; once considered the same species. Also compare with Least Flycatcher, which is very similar but has slightly shorter wingtips and a bolder eyering. Willow is larger, larger-headed, and longer-billed than other species of small flycatcher in the West; also note lack of a distinct eyering. Best identified by voice: song is a sneezing "FITZ-bew"; call is a dry "whit." Silent birds, especially in migration, often best left unidentified.