''Halesia'', also known as silverbell or snowdrop tree, is a small

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of four or five species of

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, ...

large shrubs or 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 ...

s in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Styracaceae.

Range

They are

native Native may refer to: People * Jus soli, citizenship by right of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Native Americans (disambiguation) In arts and entert ...

to eastern Asia (southeast China) and eastern North America (southern

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central C ...

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

south through

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 eastern

Texas Texas (, ; Spanish: ''Texas'', ''Tejas'') is a state in the South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2020, it is the second-largest U.S. state by ...

, United States).

Description

They grow to tall (rarely to ), and have alternate, simple ovate leaves 5–16 cm long and 3–8 cm broad. 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 pendulous, white or pale pink, produced in open clusters of 2–6 flowers, each flower being 1–3 cm long. 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 distinctive, oblong dry drupe 2–4 cm long. All species except ''H. diptera'' have four narrow longitudinal ribs or wings on fruit; ''diptera'' only has two, making it the most distinctive of the group.

Species

*''

Halesia carolina ''Halesia carolina'', commonly called Carolina silverbell or little silverbell, is a species of flowering plant in the family Styracaceae, native to the southeastern United States. Description It is a vigorous, fast-growing deciduous shrub o ...

'' L.; little silverbell – eastern North America ( syn. ''H. parviflora'' Michx. or ''H. tetraptera'' var. ''parviflora'' (Michx.) Schelle) *''

Halesia diptera ''Halesia diptera'', the two-wing silverbell or two-winged snowdrop tree, is a species in the family Styracaceae, native to the southeastern United States from South Carolina and Florida west to eastern Texas. It is cultivated as an ornamental ...

'' Ellis; two-wing silverbell – southeastern North America *''

Halesia macgregorii ''Halesia macgregorii'' is a species of flowering plant in the family Styracaceae. It is endemic to southeastern China, where it grows at moderate altitudes of 700–1,200 m. It is threatened by habitat loss.Flora of China''Halesia macgregorii' ...

'' Chun; Chinese silverbell or Macgregor's silverbell – eastern China *''

Halesia tetraptera ''Halesia tetraptera'', commonly known as the common silverbellKY State Nature Preserves Commission''Halesia tetraptera'' or mountain silverbell (or Carolina silverbell; syn. ''Halesia carolina'' auct. non L.), is a species in the family Styra ...

'' L.; common silverbell – eastern North America;
which includes a variety treated by some as a full species: *''

Halesia monticola ''Halesia'' (''tetraptera'' var.) ''monticola'', the mountain silverbell, is a species of flowering plant in the small family Styracaceae. This large deciduous shrub was originally included in '' H. carolina'', but was identified first as a subs ...

'' (Rehd.) Sarg.; mountain silverbell – southern

Appalachians 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 ...

and southwards ( syn. ''H. carolina'' var. ''monticola'' Rehder; ''H. carolina'' subsp. ''monticola'' (Rehder) A.E.Murray; ''H. tetraptera'' var. ''monticola'' (Rehder) Reveal & Seldin)^''cf.'' ''Halesia monticola'' is the largest of the genus, with specimens up to tall known in the

Great Smoky Mountains National Park Great Smoky Mountains National Park is an American national park in the southeastern United States, with parts in North Carolina and Tennessee. The park straddles the ridgeline of the Great Smoky Mountains, part of the Blue Ridge Mountains, w ...

North Carolina North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia and ...

; the second-largest is ''H. macgregorii'', reaching in China. The others rarely exceed tall. ''H. monticola'' is considered by some to be a subspecies of ''H. carolina'' (aka ''H. tetraptera''). However, there appears to be a consistent size difference between the two taxa.

Taxonomy

The taxonomy and naming of the American species is confused and extensively disputed. The first dispute is over the exact identity of the specimen first named by

Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

as ''H. carolina''; some contend that it is the same as ''H. parviflora'',Germplasm Resources Information Network
''Halesia''
while others say it is the same as ''H. tetraptera''. The second dispute is over whether ''H. monticola'' is sufficiently distinct from the other species to merit specific recognition or not (with its varietal placing depending on the above question, too). Neither question has yet been conclusively answered. The treatment here includes both ''H. carolina'' (small) and ''H. monticola'' (large). A

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

study suggests that ''Halesia'' is not monophyletic and as a result, the Chinese species ''Halesia macgregorii'' has been transferred into a new genus ''

Perkinsiodendron ''Perkinsiodendron'' is a genus of flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, ...

,'' named after American botanist and Styracaceae expert Janet Russell Perkins. The genus was named after

Stephen Hales Stephen Hales (17 September 16774 January 1761) was an English clergyman who made major contributions to a range of scientific fields including botany, pneumatic chemistry and physiology. He was the first person to measure blood pressure. He al ...

by John Ellis, publishing the name in the tenth edition of Linnaeus's '' Systema Naturae'' in 1759. The name is conserved as the same name had been used in an obscure earlier publication in 1756 for a different plant.

Fossil record

One

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

endocarp Fruit anatomy is the plant anatomy of the internal structure of fruit. Fruits are the mature ovary or ovaries of one or more flowers. They are found in three main anatomical categories: aggregate fruits, multiple fruits, and simple fruits. Aggr ...

of †''Halesia crassa'' has been described from a middle Miocene stratum of the Fasterholt area near

Silkeborg Silkeborg () is a Danish town with a population of 49,747 (1 January 2022).Jutland Jutland ( da, Jylland ; german: Jütland ; ang, Ēota land ), known anciently as the Cimbric or Cimbrian Peninsula ( la, Cimbricus Chersonesus; da, den Kimbriske Halvø, links=no or ; german: Kimbrische Halbinsel, links=no), is a peninsula of ...

Denmark ) , song = ( en, "King Christian stood by the lofty mast") , song_type = National and royal anthem , image_map = EU-Denmark.svg , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of Denmark , establish ...

.Angiosperm Fruits and Seeds from the Middle Miocene of Jutland (Denmark) by

Else Marie Friis Else Marie Friis (born 18 June 1947) is a Danish botanist and paleontologist. She is Professor Emerita in the Department of Geoscience at Aarhus University. Her work has been fundamental in the phylogenetic analysis of angiosperms, with widespr ...

, The Royal Danish Academy of Sciences and Letters 24:3, 1985

Cultivation and uses

Silverbells are popular

ornamental plant 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 ...

s in large gardens, grown for their delicate pendant flowers in late spring.

References

{{Taxonbar, from=Q2719926 Ericales genera Trees of the Eastern United States Flora of the Appalachian Mountains Trees of the Southeastern United States