''Hydrangea arborescens'', commonly known as smooth hydrangea or sevenbark, is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Hydrangeaceae. It is a small- to medium-sized, multi-stemmed,

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 Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...

shrub A shrub or 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 by their multiple ...

up to tall that is

native Native may refer to: People * '' Jus sanguinis'', nationality by blood * '' Jus soli'', nationality by location of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Nat ...

to the eastern United States.

Description

The inflorescence is a

corymb Corymb is a botanical term for an inflorescence with the flowers growing in such a fashion that the outermost are borne on longer pedicels than the inner, bringing all flowers up to a common level. A corymb has a flattish top with a superficial re ...

up to wide. Showy, sterile flowers are usually absent or if present they are usually less than 1 cm in diameter on the edge of the

panicles In botany, 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 p ...

. Flowering occurs May to July. Fruit is a ribbed, brown capsule about 2 mm long. Many are produced in October and persist through the winter. The leaves are large (8 to 18 cm long),

opposite In lexical semantics, opposites are words lying in an inherently incompatible binary relationship. For example, something that is ''even'' entails that it is not ''odd''. It is referred to as a 'binary' relationship because there are two members i ...

, serrated,

ovate Ovate may refer to: * Ovate (egg-shaped) leaves, tepals, or other botanical parts *Ovate, a type of prehistoric stone hand axe * Ovates, one of three ranks of membership in the Welsh Gorsedd * Vates or ovate, a term for ancient Celtic bards ...

, and

. The lower leaf surface is glabrous or with inconspicuous fine hairs, appearing green;

trichome Trichomes (; ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a plant ...

s of the lower surface are restricted to the midrib and major veins. The stem

bark Bark may refer to: Common meanings * Bark (botany), an outer layer of a woody plant such as a tree or stick * Bark (sound), a vocalization of some animals (which is commonly the dog) Arts and entertainment * ''Bark'' (Jefferson Airplane album), ...

has a peculiar tendency to peel off in several successive thin layers with different colors, hence the common name "sevenbark". Smooth hydrangea can spread rapidly by

stolon In biology, a stolon ( from Latin ''wikt:stolo, stolō'', genitive ''stolōnis'' – "branch"), also known as a runner, is a horizontal connection between parts of an organism. It may be part of the organism, or of its skeleton. Typically, animal ...

s to form colonies.

Taxonomy

At one time both ashy hydrangea ('' Hydrangea cinerea'') and silverleaf hydrangea ('' Hydrangea radiata'') were considered subspecies of smooth hydrangea.McClintock, E. 1957. A monograph of the genus ''Hydrangea''. Proceedings of the California Academy of Sciences 29: 147-256. However, most taxonomists now consider them to be separate species.Pilatowski, Ronald E. A taxonomic study of the ''Hydrangea arborescens'' complex. Castanea 47: 84-98.

Distribution and habitat

Smooth hydrangea is widely distributed across the eastern United States—from southern New York to the panhandle of Florida, west to eastern Oklahoma and southeastern Kansas. It is mainly found in mesic soils under the canopy of deciduous forests and is frequently found along small water courses and on woodland road waysides. It is common in the

Delaware River The Delaware River is a major river in the Mid-Atlantic region of the United States and is the longest free-flowing (undammed) river in the Eastern United States. From the meeting of its branches in Hancock, New York, the river flows for a ...

Valley and in the

Appalachian Mountains The Appalachian Mountains, often called the Appalachians, are a mountain range in eastern to northeastern North America. The term "Appalachian" refers to several different regions associated with the mountain range, and its surrounding terrain ...

. It is a host plant of the hydrangea sphinx moth.

Uses

This attractive shrub is often cultivated for ornamental use. In the UK the

cultivar A cultivar is a kind of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and which retains those traits when Plant propagation, propagated. Methods used to propagate cultivars include division, root a ...

'Annabelle' has gained the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr ...

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. It includes the full range of cultivated p ...

. The cultivar 'Grandiflora' has inflorescences which resemble

snowball A snowball is a sphere, spherical object made from snow, usually created by scooping snow with the hands and pressing the snow together to compact it into a ball. Snowballs are often used in games such as snowball fights. A snowball may also be ...

s, similar to ''

Viburnum opulus ''Viburnum opulus'', commonly known as the guelder-rose, or guelder rose (), is an Old World species of flowering plant in the family Adoxaceae. Description ''Viburnum opulus'' is a deciduous shrub growing to tall. The leaves are opposite, th ...

'' 'Roseum'. Smooth hydrangea root was used medicinally by the

Cherokee The Cherokee (; , or ) people are one of the Indigenous peoples of the Southeastern Woodlands of the United States. Prior to the 18th century, they were concentrated in their homelands, in towns along river valleys of what is now southwestern ...

, and later, by early settlers for treatment of kidney and bladder stones. It has additionally been marked as a pollinator plant, supporting and attracting bees and butterflies.

Gallery

File:Hydrangea arborescens annabelle.JPG, 'Annabelle' File:Hills-of-Snow Hydrangea arborescens 'Grandiflora' Flowers 2606px.jpg, 'Grandiflora' File:2020 year. Herbarium. Hydrangea arborescens. img-035.jpg, Leaf adaxial side. File:2020 year. Herbarium. Hydrangea arborescens. img-036.jpg, Leaf abaxial side.

References

External links

Cook, Will. Trees, shrubs, and woody vines of North Carolina. Wild Hydrangea (''Hydrangea arborescens'').
Large-format diagnostic photos and information

- Informative but non-scholarly essay on Hydrangea (Culture, History and Etymology).

{{Taxonbar, from=Q278173 arborescens Flora of the Northeastern United States Flora of the Southeastern United States Flora of the United States Flora of Alabama Natural history of the Great Smoky Mountains Plants used in traditional Native American medicine Plants described in 1753 Taxa named by Carl Linnaeus