The species comprises two distinct subspecies that may merit specific status.
"Yellow Palm-Warbler" (D. p. hypochrysea) of the eastern third of the breeding range has brownish-olive upper parts and thoroughly yellow underparts with bold rufous breast and flank streaking. It migrates later in the fall than its western counterpart.
"Western Palm-Warbler" (D. p. palmarum) inhabits the remaining western two-thirds of the breeding range. It has much less yellow below, with less colorful streaking, and cold grayish-brown upper parts.
Palm Warblers breed in open coniferous bogs and edge east of the Continental Divide, across Canada and the northeastern United States. Their nests take the form of an open cup, usually situated on or near the ground in an open area.
Palm Warblers forage on the ground much more than other warblers, sometimes flying to catch insects. These birds mainly eat insects and berries.
The song of this bird is a monotonous buzzy, trill. The call is a sharp chek.
- ^ "Palm Warbler". All About Birds. Cornell Laboratory of Ornithology. http://www.birds.cornell.edu/AllAboutBirds/BirdGuide/Palm_Warbler.html. Retrieved 2008-10-12.