Oxydendrum

Oxydendrum arboreum

Oxydendron arboreum-foliage

Sourwood raceme Keeler

Oxydendron arboreum JPG1

Sourwood in autumn (foliage closeup)

Oxydendrum is a genus of flowering plants in the family Ericaceae, native to eastern North America. This genus is monotypic, containing only one species, Oxydendrum arboreum, commonly known as the sourwood or sorrel tree. The sourwood is notable for its distinctive summer flowers, brilliant autumn foliage, and the sour taste of its leaves, from which its common name is derived.

Description

Oxydendrum arboreum is a deciduous tree that can grow up to 10-20 meters (about 30-65 feet) tall, with a slender trunk and a narrow, oval to rounded crown. The leaves are alternate, simple, lanceolate to oblong, 5-20 cm long and 2-5 cm broad, with a finely serrated margin. They are green above and paler below, turning vibrant shades of red, orange, and purple in the fall.

The flowers are white, bell-shaped, 6-10 mm long, arranged in slender, drooping panicles 15-25 cm in length, blooming in late summer. The fruit is a small, five-valved capsule containing numerous seeds.

Habitat and Distribution

Oxydendrum arboreum is found in the eastern United States, from Pennsylvania south to Florida and west to Louisiana. It prefers acidic, well-drained soils and is commonly found in the understory of hardwood forests, often on slopes and ridges.

Ecology

The sourwood tree is an important source of nectar for bees, and its honey is highly prized for its unique flavor. The tree is also host to various species of butterflies and moths.

Uses

While not widely used for timber due to its small size and irregular form, sourwood is valued for ornamental purposes because of its attractive summer flowers and brilliant fall foliage. Sourwood honey is a sought-after varietal honey, celebrated for its complex, spicy-sweet flavor.

Conservation

Currently, Oxydendrum arboreum does not face any immediate threats and is not listed on the IUCN Red List of Threatened Species. However, like many forest species, it could be affected by changes in land use and climate change.

See Also

• Ericaceae
• Deciduous trees
• Flora of the Eastern United States