In wooded areas coast to coast, throughout late spring and summer, some of the most characteristic sounds are the songs of wood-pewees. The sound changes abruptly at mid-continent because two species — Eastern and Western Wood-Pewees — divide the lower 48 states almost exactly in half, along a line extending from the Dakotas south to Texas.
These trim gray flycatchers tend to perch high, often among foliage, so they are heard more often than they are seen. That’s just as well because they are far more distinctive by sound than by sight. Both are relatively plain, a little larger than the tricky Empidonax flycatchers, with wing bars but no eye-rings. No diagnostic visual marks will help you tell them apart.