Females and juveniles are olive green with yellowish stomachs and undersides. Male orchard orioles have deep ochre chestnut markings on their stomach, shoulders and backsides. They are black everywhere else with white wing bars. Young males don’t get their colorful plumage until they are about two years old. The females and juveniles are easy to confuse with warblers. 

Smaller and slimmer than a Baltimore oriole, orchard orioles are typically about 6 to 7 inches (15 to 18 centimeters) long with a wingspan of 10 inches (25 centimeters) and weigh about 1 ounce (28 grams). 

Orchard orioles live in semi-open areas with deciduous trees, including farmland, gardens and suburban yards. They can also be found in in open woodland parks, especially along lakes and streams.  

The oldest recorded orchard oriole was 11 years old. Average lifespan is unknown.

Males sing from treetops to attract mates during the breeding season. Their songs are whistle-like, almost comparable to a high-pitched American robin, though the orchard oriole’s songs are more varied, like that of a finch. Their call notes include a soft “chuck” and quiet chatters. 

During courtship displays, both sexes use body language to communicate, including bowing, bobbing and begging. Males also use a flight display that includes bobbing their heads and tails while flying.

Orchard orioles prefer nectar, fruit and insects. During the summer months they mostly eat insects and small arthropods, including crickets, wasps, caterpillars, beetles, grasshoppers, spiders and ants, as well as agricultural pests like cotton boll weevils and plant lice. Shortly before migration in late summer, they begin eating as much fruit and nectar as they can, including mulberries, chokecherries and other berries. In the wintering grounds they eat mainly nectar and fruit. 

Except during migration they are active during the day—especially at dawn and dusk—and sleep at night. They migrate in flocks through the darkest parts of the night. 

Orchard orioles migrate in large flocks. They are loosely territorial and will nest in the same trees as kingbirds or even other orchard orioles. 

Males sing to attract females and will also feed potential mates. Breeding pairs may bond for life or find new mates each year. They typically only have one brood per year, but if a nest fails early enough in the season they may start again.

Females weave hanging cup-shaped nests out of grasses, preferring trees like willows, elms and pecans with small branches that let plenty of light penetrate. They line their nests with soft materials including fine grasses, animal wool and feathers. One week after finishing the nest, the female lays between four and six eggs. The eggs are a very pale blue with dark brown or purple speckles, mostly on the wide end of the egg.

The female sits on the eggs 12 to 14 days while the male brings her food. The male defends the nesting territory from larger birds including grackles and, in the Southwest U.S., roadrunners. After hatching, both parents feed the babies for 11 to 14 days. Once the fledglings leave the nest, they stay in trees or other densely covered habitat close to their nest for about one week while their parents continue to feed them occasionally.

After that week, the males begin migrating to the warmer wintering grounds. The females and young remain slightly longer before flying south in flocks with other females and adolescents.

Orchard orioles are a species of least concern, though their numbers have been decreasing. Urbanization, especially changes to rivers, and climate change may be the biggest threats they face. Spraying for pesticides may also decrease their populations.