''Oxydendrum arboreum'', the sourwood or sorrel tree, is the sole

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

in the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

''Oxydendrum'', in the family

Ericaceae The Ericaceae are a family of flowering plants, commonly known as the heath or heather family, found most commonly in acidic and infertile growing conditions. The family is large, with c.4250 known species spread across 124 genera, making it th ...

. It is native to eastern

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

, from southern

Pennsylvania Pennsylvania (; ( Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, ...

south to northwest

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

and west to southern

Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. Its largest metropolitan areas include the Chicago metropolitan area, and the Metro East section, of Greater St. Louis. Other smaller metropolita ...

; it is most common in the lower chain of the

Appalachian Mountains The Appalachian Mountains, often called the Appalachians, (french: Appalaches), are a system of mountains in eastern to northeastern North America. The Appalachians first formed roughly 480 million years ago during the Ordovician Period. They ...

. The tree is frequently seen as a component of oak-heath forests. Oxydendron arboreum-foliage

Growth

Sourwood is a small

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...

or large

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

, growing to tall with a trunk up to diameter. Occasionally on extremely productive sites, this species can reach heights in excess of 30 meters and 60 cm diameter. The

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

are alternately arranged,

deciduous In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...

, long and broad, with a finely

serrated Serration is a saw-like appearance or a row of sharp or tooth-like projections. A serrated cutting edge has many small points of contact with the material being cut. By having less contact area than a smooth blade or other edge, the applied p ...

margin; they are dark green in summer, but turn vivid red in fall. The

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

s are white, bell-shaped, 6–9 mm ( 1/4 to 1/3 inch) long, produced on long

panicle A panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a panicle are of ...

s. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

is a small woody capsule. The

root In vascular plants, the roots are the organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often below the sur ...

s are shallow, and the tree grows best when there is little root competition; it also requires

acidic soil Soil pH is a measure of the acidity or basicity (alkalinity) of a soil. Soil pH is a key characteristic that can be used to make informative analysis both qualitative and quantitatively regarding soil characteristics. pH is defined as the neg ...

s for successful growth. The leaves can be chewed (but should not be swallowed) to help alleviate a dry-feeling mouth.

Description

The bark is gray with a reddish tinge, deeply furrowed and scaly. Branchlets at first are light yellow green, but later turn reddish brown. The wood is reddish brown, with paler sapwood; it is heavy, hard, and close-grained, and will take a high polish. Its specific gravity is 0.7458, with a density of 46.48 lb/cu ft. The winter buds are axillary, minute, dark red, and partly immersed in the bark. Inner scales enlarge when spring growth begins. Leaves are

alternate Alternative or alternate may refer to: Arts, entertainment and media * Alternative (''Kamen Rider''), a character in the Japanese TV series ''Kamen Rider Ryuki'' * ''The Alternative'' (film), a 1978 Australian television film * ''The Alternative ...

, four to seven inches long, 1.5 to 2.5 inches wide, oblong to

oblanceolate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...

, wedge-shaped at the base, serrate, and acute or

acuminate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...

. Leaf veins are

feather-veined A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, st ...

, the

midrib This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary o ...

is conspicuous. They emerge from the bud revolute, bronze green and shining, and smooth; when full-grown, they are dark green, shining above, and pale and glaucous below. In autumn, they turn bright scarlet. Petioles are long and slender, with

stipule In botany, a stipule is an outgrowth typically borne on both sides (sometimes on just one side) of the base of a leafstalk (the petiole). Stipules are considered part of the anatomy of the leaf of a typical flowering plant, although in many speci ...

s wanting. They are heavily laden with acid. In June and July, cream-white flowers are borne in terminal panicles of secund

raceme A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the s ...

s seven to eight inches long; rachis and short pedicels are downy. The calyx is five-parted and persistent; lobes are valvate in bud. The corolla is ovoid-cylindric, narrowed at the throat, cream-white, and five-toothed. The 10

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filame ...

s are inserted on the corolla; filaments are wider than the

anther The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filam ...

s; anthers are two-celled. The

pistil Gynoecium (; ) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) ''pistils'' ...

is ovary superior, ovoid, and five-celled; the style is columnar; the stigma is simple; the disk is ten-toothed, and ovules are many. The fruit is a capsule, downy, five-valved, five-angled, and tipped by the persistent style; the

pedicels In botany, a pedicel is a stem that attaches a single flower to the inflorescence. Such inflorescences are described as ''pedicellate''. Description Pedicel refers to a structure connecting a single flower to its inflorescence. In the absenc ...

are curving.

Cultivation and uses

The sourwood is perfectly hardy in the north and a worthy

ornamental tree Ornamental plants or garden plants are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars that i ...

in lawns and parks. Its late bloom makes it desirable, and its autumnal coloring is particularly beautiful and brilliant. The leaves are heavily charged with acid, and to some extent have the poise of those of the

peach The peach (''Prunus persica'') is a deciduous tree first domesticated and cultivated in Zhejiang province of Eastern China. It bears edible juicy fruits with various characteristics, most called peaches and others (the glossy-skinned, non-fu ...

. The leaves are also a

laxative Laxatives, purgatives, or aperients are substances that loosen stools and increase bowel movements. They are used to treat and prevent constipation. Laxatives vary as to how they work and the side effects they may have. Certain stimulant, lubri ...

. It is renowned for

nectar Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists ...

, and for the

honey Honey is a sweet and viscous substance made by several bees, the best-known of which are honey bees. Honey is made and stored to nourish bee colonies. Bees produce honey by gathering and then refining the sugary secretions of plants (primar ...

which is produced from it.''National Audubon Society Field Guide to Trees, Eastern Region, North America'', 2003, page 626 Juice from its blooms is used to make sourwood jelly. The shoots were used by the

Cherokee The Cherokee (; chr, ᎠᏂᏴᏫᏯᎢ, translit=Aniyvwiyaʔi or Anigiduwagi, or chr, ᏣᎳᎩ, links=no, translit=Tsalagi) are one of the indigenous peoples of the Southeastern Woodlands of the United States. Prior to the 18th century, t ...

and the

Catawba Catawba may refer to: *Catawba people, a Native American tribe in the Carolinas *Catawba language, a language in the Catawban languages family *Catawban languages Botany *Catalpa, a genus of trees, based on the name used by the Catawba and other N ...

to make arrowshafts.

In Appalachian culture

Sourwood Mountain "Sourwood Mountain" is a traditional American folk song. Like many folk songs, there are numerous lyrical versions extant; however, there are certain commonalities. The song's theme is a lament over the narrator's true love, from whom he is separ ...

is a popular old-time tune in the Appalachian region of the United States.

Gallery

Image:Oxydendron arboreum JPG1.jpg, Trunk and leaves Image:Sourwood in autumn (foliage closeup).JPG, Sourwood in autumn foliage on top of Pilot Mtn., NC. (10-30-2008)

References

External links

''Oxydendrum arboreum'' images at bioimages.vanderbilt.edu
{{Authority control Vaccinioideae Trees of the Southeastern United States Trees of the Northeastern United States Trees of the North-Central United States Trees of the Great Lakes region (North America) Flora of the Appalachian Mountains Natural history of the Great Smoky Mountains Medicinal plants of North America Monotypic Ericaceae genera