''Ulmus thomasii'', the rock elm
or cork elm (or orme liège in
Québec
Quebec ( ; )According to the Government of Canada, Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is ...
), is a
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 ...
tree native primarily to the
Midwestern United States
The Midwestern United States, also referred to as the Midwest or the American Midwest, is one of four census regions of the United States Census Bureau (also known as "Region 2"). It occupies the northern central part of the United States. I ...
. The tree ranges from 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 Ca ...
and
Quebec
Quebec ( ; )According to the Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is one of the thirtee ...
, south to
Tennessee
Tennessee ( , ), officially the State of Tennessee, is a landlocked state in the Southeastern region of the United States. Tennessee is the 36th-largest by area and the 15th-most populous of the 50 states. It is bordered by Kentucky to th ...
, west to northeastern
Kansas
Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the ...
, and north to
Minnesota
Minnesota () is a state in the upper midwestern region of the United States. It is the 12th largest U.S. state in area and the 22nd most populous, with over 5.75 million residents. Minnesota is home to western prairies, now given over to ...
.
Etymology
The tree was named in 1902 for David Thomas, an American
civil engineer
A civil engineer is a person who practices civil engineering – the application of planning, designing, constructing, maintaining, and operating infrastructure while protecting the public and environmental health, as well as improving existing ...
who had first named and described the tree in 1831 as ''Ulmus racemosa''.
Description
''Ulmus thomasii'' grows as a tree from tall, and may live for up to 300 years. Where forest-grown, the crown is cylindrical and upright with short branches, and is narrower than most other elms. Rock elm is also unusual among North American elms in that it is often
monopodial
Vascular plants with monopodial growth habits grow upward from a single point. They add leaves to the apex each year and the stem grows longer accordingly. The word ''Monopodial'' is derived from Greek "mono-", ''one'' and "podial", "foot", in refe ...
.
[Bean, W. J. (1981). ''Trees and shrubs hardy in Great Britain'', 7th edition. Murray, London.] The
bark is grey-brown and deeply furrowed into scaly, flattened ridges. Many older branches have 3–4 irregular thick corky wings. It is for this reason the rock elm is sometimes called the cork elm.
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 long and wide,
oval
An oval () is a closed curve in a plane which resembles the outline of an egg. The term is not very specific, but in some areas (projective geometry, technical drawing, etc.) it is given a more precise definition, which may include either one or ...
to
obovate
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 ...
with a round, symmetrical base and acuminate apex. The leaf surface is shiny dark green, turning bright yellow in autumn; the underside is
pubescent The adjective pubescent may describe:
* people or animals undergoing puberty
* plants that are hairy, covered in trichomes
* insects that are covered in setae
In biology, setae (singular seta ; from the Latin word for "bristle") are any of a ...
. The
perfect apetalous
Petals are modified leaves that surround the reproductive parts of flowers. They are often brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corolla''. Petals are usually ...
,
wind-pollinated
Anemophily or wind pollination is a form of pollination whereby pollen is distributed by wind. Almost all gymnosperms are anemophilous, as are many plants in the order Poales, including grasses, sedges, and rushes. Other common anemophilous plan ...
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 red-green and appear in racemes up to long two weeks before the leaves from March to May, depending on the tree's location. 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 broad ovate
samara
Samara ( rus, Сама́ра, p=sɐˈmarə), known from 1935 to 1991 as Kuybyshev (; ), is the largest city and administrative centre of Samara Oblast. The city is located at the confluence of the Volga and the Samara (Volga), Samara rivers, with ...
long covered with fine hair, notched at the tip, and maturing during May or June to form drooping clusters at the leaf bases.
[White, J & More, D. (2003). ''Trees of Britain & Northern Europe''. Cassell's, London.]
Although ''U. thomasii'' is
protandrous
Sequential hermaphroditism (called dichogamy in botany) is a type of hermaphroditism that occurs in many fish, gastropods, and plants. Sequential hermaphroditism occurs when the individual changes its sex at some point in its life. In particular, ...
, levels of self-pollination remain high.
File:The North American sylva; or, A description of the forest trees of the United States, Canada and Nova Scotia. Considered particularly with respect to their use in the arts and their introduction into (14778570501).jpg, ''U. racemosa'' ''U. thomasii''diagnostic illustration (1865)
File:A guide to the trees (Page 123) (8434849285).jpg, ''U. racemosa'' ''U. thomasii''diagnostic illustration (1900)
File:The tree book - A popular guide to a knowledge of the trees of North America and to their uses and cultivation (1920) (14782984355).jpg, ''U. thomasii'' shoot and buds (1920)
File:Ulmus thomasii (meisse) leaves 2.jpg, ''U. thomasii'' leaves, Meisse
File:SHHG Rock Elm leaf.jpg, ''U. thomasii'' leaves, Sir Harold Hillier Gardens, England
File:Ulmus thomasii (meisse) bark.jpg, ''U. thomasii'' bark, Meisse
File:Ulmus thomasii (meisse) corky wings.jpg, ''U. thomasii'' corky twig, Meisse
Ecology
''Ulmus thomasii'' is moderately shade-tolerant. Its preferred habitat is moist but well-drained sandy loam, loam, or silt loam soil, mixed with other
hardwood
Hardwood is wood from dicot trees. These are usually found in broad-leaved temperate and tropical forests. In temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen. Hardwood (which comes from ...
s. However, it also grows on dry uplands, especially on rocky ridges and
limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...
bluffs.
Pests and diseases
Like most North American
elm
Elms are deciduous and semi-deciduous trees comprising the flowering plant genus ''Ulmus'' in the plant family Ulmaceae. They are distributed over most of the Northern Hemisphere, inhabiting the temperate and tropical-montane regions of North ...
s, ''U. thomasii'' is very susceptible to
Dutch elm disease
Dutch elm disease (DED) is caused by a member of the sac fungi (Ascomycota) affecting elm trees, and is spread by elm bark beetles. Although believed to be originally native to Asia, the disease was accidentally introduced into Americas, America ...
.
Cultivation
There are no known
cultivar
A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture, ...
s of ''Ulmus thomasii'', nor is it known to be any longer in commerce. It appeared in some US nursery catalogues in the early 20th century. The species is occasionally grown beyond its native range as a specimen tree in
botanical garden
A botanical garden or botanic gardenThe terms ''botanic'' and ''botanical'' and ''garden'' or ''gardens'' are used more-or-less interchangeably, although the word ''botanic'' is generally reserved for the earlier, more traditional gardens, an ...
s and
arboreta
An arboretum (plural: arboreta) in a general sense is a botanical collection composed exclusively of trees of a variety of species. Originally mostly created as a section in a larger garden or park for specimens of mostly non-local species, man ...
, for example in northwestern Europe, but not commonly cultivated in northern Europe, being unsuited to the region's more temperate, maritime climate. However, the tree was propagated and marketed in the UK by the Hillier & Sons nursery,
Winchester, Hampshire
Winchester is a cathedral city in Hampshire, England. The city lies at the heart of the wider City of Winchester, a local government district, at the western end of the South Downs National Park, on the River Itchen. It is south-west of Londo ...
, from 1965 to 1977, during which time 49 were sold.
[Hillier & Sons (1977). ''Catalogue of Trees & Shrubs''. Hillier, Ampfield, UK.][Hillier & Sons ''Sales inventory 1962 to 1977'' (unpublished).]
''Ulmus thomasii'' was crossed experimentally with
Japanese elm Japanese elm is a common name for several plants and may refer to:
* ''Ulmus davidiana'' var. ''japonica''
*''Zelkova serrata
''Zelkova serrata'' (Japanese zelkova, Japanese elm or keyaki or keaki; ja, 欅 (ケヤキ) keyaki /槻 (ツキ) tsu ...
(''U. davidiana'' var. ''japonica'') at the
Arnold Arboretum
The Arnold Arboretum of Harvard University is a botanical research institution and free public park, located in the Jamaica Plain and Roslindale neighborhoods of Boston, Massachusetts. Established in 1872, it is the oldest public arboretum in N ...
in
, but no clones were released to commerce.
Seedlings arising from crossings with
Siberian elm
''Ulmus pumila'', the Siberian elm, is a tree native to Asia. It is also known as the Asiatic elm and dwarf elm, but sometimes miscalled the 'Chinese Elm' (''Ulmus parvifolia''). ''U. pumila'' has been widely cultivated throughout Asia, Nor ...
(''U. pumila'') at the Lake States Forestry Experimental Station in the 1950s all perished,
[Sholtz, H. F. (1957). Rock Elm (Ulmus thomasii). ''Lake States Forest Experimental Station Paper'' 47:16.] a classic case of
hybrid lethality.
Notable trees
The US National Champion, measuring high in 1989, grows in
Cass County, Michigan
Cass County is a county in the U.S. state of Michigan. As of the 2020 Census, the population was 51,589. Its county seat is Cassopolis.
Cass County is included in the South Bend–Mishawaka, IN-MI, Metropolitan Statistical Area which has a t ...
.
Uses
The
wood
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin th ...
of the rock elm is the hardest and heaviest of all elms, and where forest-grown remains comparatively free of knots and other defects. It is also very strong and takes a high polish, and consequently was once in great demand in America and Europe for a wide range of uses, notably
boatbuilding
Boat building is the design and construction of boats and their systems. This includes at a minimum a hull, with propulsion, mechanical, navigation, safety and other systems as a craft requires.
Construction materials and methods
Wood
Wo ...
,
furniture
Furniture refers to movable objects intended to support various human activities such as seating (e.g., stools, chairs, and sofas), eating (tables), storing items, eating and/or working with an item, and sleeping (e.g., beds and hammocks). Fu ...
,
agricultural tools, and
musical instrument
A musical instrument is a device created or adapted to make musical sounds. In principle, any object that produces sound can be considered a musical instrument—it is through purpose that the object becomes a musical instrument. A person who pl ...
s.
Much of the timber's strength is derived from the tight grain arising from the tree's very slow rate of growth, the trunk typically increasing in diameter by less than a year. Over 250 annual growth rings were once counted in a log square being sawn for
gunwale
The gunwale () is the top edge of the hull of a ship or boat.
Originally the structure was the "gun wale" on a sailing warship, a horizontal reinforcing band added at and above the level of a gun deck to offset the stresses created by firing ...
s in an English boatyard, while a tree once grown at
Kew Gardens
Kew Gardens is a botanical garden, botanic garden in southwest London that houses the "largest and most diverse botany, botanical and mycology, mycological collections in the world". Founded in 1840, from the exotic garden at Kew Park, its li ...
,
London
London is the capital and largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary down to the North Sea, and has been a majo ...
, attained a height of only in 50 years.
[Elwes, H. J. & Henry, A. (1913). ]
The Trees of Great Britain & Ireland
'. Vol. VII. 1848–1929. Republished 2004 Cambridge University Press,
Accessions
;North America
*
Arnold Arboretum
The Arnold Arboretum of Harvard University is a botanical research institution and free public park, located in the Jamaica Plain and Roslindale neighborhoods of Boston, Massachusetts. Established in 1872, it is the oldest public arboretum in N ...
,
, US. Acc. no. 444-88.
*
Brenton Arboretum
The Brenton Arboretum is a 141-acre arboretum and public garden in Dallas Center, Iowa, United States, established in 1997. The arboretum displays 175 native Iowa trees and shrubs suitable to the site, as well as many other tree species which ca ...
,
Dallas Center
Dallas Center is a city in Dallas County, Iowa, United States. The population was 1,901 during the 2020 census. It is part of the Des Moines–West Des Moines Metropolitan Statistical Area.
History
Dallas Center got its start in the year 1869, f ...
,
Iowa
Iowa () is a state in the Midwestern region of the United States, bordered by the Mississippi River to the east and the Missouri River and Big Sioux River to the west. It is bordered by six states: Wisconsin to the northeast, Illinois to the ...
, US. No acc. details available.
*
Dominion Arboretum
The Dominion Arboretum (french: Arboretum du Dominion) is an arboretum part of the Central Experimental Farm of Agriculture and Agri-Food Canada in Ottawa, Ontario, Canada. Originally begun in 1889, the Arboretum covers about of rolling land ...
,
Ottawa
Ottawa (, ; Canadian French: ) is the capital city of Canada. It is located at the confluence of the Ottawa River and the Rideau River in the southern portion of the province of Ontario. Ottawa borders Gatineau, Quebec, and forms the core ...
, Canada. No acc. details.
*
Morton Arboretum
The Morton Arboretum, in Lisle, Illinois, United States, is a public garden, and outdoor museum with a library, herbarium, and program in tree research including the Center for Tree Science. Its grounds, covering 1,700 acres (6.9 square kilometres ...
,
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 ...
, US. Acc. no. 178-84, wild collected from
Reedsville, Wisconsin
Reedsville is a village in Manitowoc County, Wisconsin, United States. The population was 1,206 at the 2010 census.
History
The village was named after Judge George Reed, who, with his partner, Jacob Lueps, bought a section of land in the town ...
; 843-2005 (
Kelleys Island
Kelleys Island is both a village in Erie County, Ohio, and the island which it fully occupies in Lake Erie. The British originally called it Sandusky Island. Later the United States took it over and officially designated it as Island Number 6 ...
,
Erie County,
Ohio
Ohio () is a state in the Midwestern region of the United States. Of the fifty U.S. states, it is the 34th-largest by area, and with a population of nearly 11.8 million, is the seventh-most populous and tenth-most densely populated. The sta ...
); 122-2006 (
Dixon County
History
Dixon County was formed in 1856. Dixon was named for an early settler.
Dixon County is a county in the U.S. state of Nebraska. As of the 2010 United States Census, the population was 6,000. Its county seat is Ponca. The county was creat ...
,
Nebraska
Nebraska () is a state in the Midwestern region of the United States. It is bordered by South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Kansas to the south; Colorado to the southwe ...
).
*
Nebraska Statewide Arboretum
The grounds surrounding the Joslyn Castle included an urban farm, vegetable gardens and over 100 fruit trees.jpg, The grounds surrounding the Joslyn Castle included an urban farm, vegetable gardens and over 100 fruit trees
The Nebraska Statewide ...
, US. No details available.
;Europe
*
Grange Farm Arboretum
The Grange Farm Arboretum is a small private arboretum comprising 3 hectares accommodating over 800 trees, mostly native and ornamental species or cultivars, notably oaks, ashes, walnuts and elms, growing on a calcareous loam.Ostler, J. (2009) ' ...
,
Lincolnshire
Lincolnshire (abbreviated Lincs.) is a county in the East Midlands of England, with a long coastline on the North Sea to the east. It borders Norfolk to the south-east, Cambridgeshire to the south, Rutland to the south-west, Leicestershire ...
, UK. Acc. no. 706.
*
National Botanic Garden of Belgium
The Meise Botanic Garden ( nl, Plantentuin Meise, french: Jardin botanique de Meise), until 2014 called the National Botanic Garden of Belgium ( nl, Nationale Plantentuin van België, french: Jardin Botanique National de Belgique), is a botani ...
,
Meise
Meise () is a municipality located in the Belgian province of Flemish Brabant. The municipality comprises the towns of Meise proper and Wolvertem (a ''deelgemeente''), and, several smaller villages like Sint-Brixius-Rode, Oppem, Meusegem, Impde/I ...
, Belgium. Acc. no. 19800105.
*
National Botanic Gardens, Ireland,
Glasnevin
Glasnevin (, also known as ''Glas Naedhe'', meaning "stream of O'Naeidhe" after a local stream and an ancient chieftain) is a neighbourhood of Dublin, Ireland, situated on the River Tolka. While primarily residential, Glasnevin is also home t ...
, Ireland. Location: A3 (155)
*
Sir Harold Hillier Gardens
The Sir Harold Hillier Gardens is an arboretum comprising 72 hectares (180 acres) accommodating over 42,000 trees and shrubs in about 12,000 taxa, notably a collection of oaks, camellia, magnolia and rhododendron.
The Gardens are located nor ...
,
Hampshire
Hampshire (, ; abbreviated to Hants) is a ceremonial county, ceremonial and non-metropolitan county, non-metropolitan counties of England, county in western South East England on the coast of the English Channel. Home to two major English citi ...
, UK. Acc. no. 2008.0419, wild collected in Ontario, Canada, by Kristl Walek
*
Wakehurst Place Garden Wakehurst Place
Wakehurst, previously known as Wakehurst Place, is a house and botanic gardens in West Sussex, England, owned by the National Trust but used and managed by the Royal Botanic Gardens, Kew. It is near Ardingly, West Sussex in the High Weald (g ...
, UK. Acc. no. 1968-48603.
References
External links
*
*
Arnold Arboretum
The Arnold Arboretum of Harvard University is a botanical research institution and free public park, located in the Jamaica Plain and Roslindale neighborhoods of Boston, Massachusetts. Established in 1872, it is the oldest public arboretum in N ...
specimen, 1960
* Labeled ''U. racemosa'', RBGE specimen from
Späth nursery The Späth (often spelt ''Spaeth'') family created one of the world's most notable plant nurseries of the 19th and early 20th centuries. The nursery had been founded in 1720 by Christoph Späth but removed to the erstwhile district of Baumschulen ...
, 1902
* Labeled ''U. racemosa'', RBGE specimen from
Späth nursery The Späth (often spelt ''Spaeth'') family created one of the world's most notable plant nurseries of the 19th and early 20th centuries. The nursery had been founded in 1720 by Christoph Späth but removed to the erstwhile district of Baumschulen ...
, 1902
* Labeled ''U. racemosa'', RBGE specimen from
Späth nursery The Späth (often spelt ''Spaeth'') family created one of the world's most notable plant nurseries of the 19th and early 20th centuries. The nursery had been founded in 1720 by Christoph Späth but removed to the erstwhile district of Baumschulen ...
, 1902
{{Taxonbar, from=Q1147786
thomasii
Trees of the Northeastern United States
Trees of the Great Lakes region (North America)
Trees of the Plains-Midwest (United States)
Trees of Canada
Trees of the North-Central United States
Trees of Ontario
Trees of Quebec
Trees of the Southeastern United States
Ulmus articles with images
Elm species and varieties