Greenish-buff head, central crown stripe, and nape; dark striping on head; wings dark chestnut with some buff markings; tail dark with chestnut markings; streaking on chest and flanks; belly white. 13 cm (5 in) in length. The head appears flat and large, and the tail is forked. The song of the Henslow's Sparrow is a short se-lick.
The breeding season begins in mid-May, peaks later that month until mid-June, and extends into early July. Breeding habitat includes wet grassy areas. The nest is usually either on the ground or suspended in the vegetation up to 15 cm (6 in) above the ground. Ground nests are commonly near the base of a tuft of grass to provide some protection. Occasionally, birds will create a roof by bending and weaving vegetation over the nest. The nest is built out of grass and other plant material. The female lays 3-5 eggs that she incubates for approximately 11 days. The young are altricial and fledge 9-10 days after hatching. Both adults feed and brood the young while they are in the nest and feed them for a period after they leave the nest.
Habitats other than those for breeding includes wet grassy areas in pine woodlands. The Henslow's Sparrow is mostly insectivorous, but also eats spiders, snails, and seeds. Most of the food is found by searching the ground and low vegetation. This species is migratory, but most birds spend the winter in the United States
Most Henslow's Sparrows breed in the northern areas of eastern United States. They spend winters in southern coastal areas in the Southeast, and during this time may breed in low numbers in Virginia and Kentucky. Within Georgia, wintering Henslow's Sparrows occur in the southern two-thirds of the state.
The Henslow's Sparrow is a species of concern throughout most of its southeastern range. Because of its preferences for moist grasslands, mowing and draining low-lying fields causes great disturbance for these birds.
In the eastern United States, the most similar species are the Savannah Sparrow and the Grasshopper Sparrow. The Savannah Sparrow has distinctive yellow on the lores,the area between the bill and the eyes, and on its eyebrow. The Grasshopper Sparrow lacks the greenish color of the head and has almost no streaking on the breast and belly.