13-15 cm (5-6") Common in boreal forests, swamps, bogs; deciduous forests during migration.
Proportionately large-headed and short-tailed. Greenish upperparts, yellowish below - from throat to belly. Distinct eye ring. Distinct wing bars. No other eastern empidonax has a yellow throat.
Song: a soft "che-bunk" similar to Least Flycatcher's; best told by its call - an ascending two note whistled "per-wee".