Handsome small songbird of fields and wetlands with extensive reedy cover. Both sexes light brown with white-bordered dark mask. Male has a gray crown with rufous tones in wings and neck, female more uniformly colored above. Flies lightly and bouncily; flying flocks cluster tightly together. Forms large flocks in the winter, when they sometimes feed with reed buntings. Calls are high-pitched and thin, often with a rasping quality.