Very common in deciduous trees in open areas, woodland edges, and wet areas with willows. A solidly built warbler with average proportions and smooth contours. Its song ‘sweet sweet I’m so sweet,’ is the sound of summer. Loud call note. First to leave, some heading s. by early Jul. ID: Many shades of yellow with bold yellow edges to tail feathers, a giveaway even with briefest view. Also yellow fringes to dark-centered wing feathers on a generally uniform bird. Round eyering, black eye, and dark bill stand out on plain face. Ad ♂: bright yellow with red streaks in summer, mostly gone by fall. Ad ♀/1st-yr ♂: slightly paler than ad ♂ with hint of breast streaks. 1st-yr ♀: dull, some with few yellow tones. Always check tail pattern. Many ssp. The ‘Golden’ group, mostly in W Indies, occurs in FL Keys. ♂ has bolder streaking, some ♀/imms are grayer, particularly on head. ‘Mangrove,’ given full species status by some, breeds on S Padre Is,TX. Ad ♂ has chestnut head in summer.