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Elms are deciduous and semi-deciduous trees comprising the genus Ulmus in the plant family Ulmaceae. The genus first appeared in the Miocene geological period about 20 million years ago, originating in what is now central Asia. These trees flourished and spread over most of the Northern Hemisphere, inhabiting the temperate and tropical-montane regions of North America and Eurasia, ranging southward across the Equator into Indonesia.
Elms are components of many kinds of natural forests; during the 19th and early 20th centuries, many species and cultivars were also planted as ornamental street, garden, and park trees in Europe, North America, and parts of the Southern Hemisphere, notably Australasia. Some individual elms reached great size and age. However, in recent decades, most mature elms of European or North American origin have died from Dutch elm disease, caused by a microfungus dispersed by bark beetles. In response, disease-resistant cultivars have been developed, capable of restoring the elm to forestry and landscaping.
Elm leaves are alternate, with simple, single- or, most commonly, doubly serrate margins, usually asymmetric at the base and acuminate at the apex. The genus is hermaphroditic, having apetalous perfect flowers which are mostly wind-pollinated, although bees do visit them. The fruit is a round wind-dispersed samara flushed with chlorophyll, facilitating photosynthesis before the leaves emerge. All species are tolerant of a wide range of soils and pH levels but, with few exceptions, demand good drainage.
The other genera of the Ulmaceae are Planera (water elm) and Zelkova (zelkova). The genus Celtis (hackberry or nettle tree), formerly included in the Ulmaceae, is now included in the family Cannabaceae.
- 1 Taxonomy
- 2 Pests and diseases
- 3 Uses of elms in landscaping
- 4 Other uses of elms
- 5 Genetic resource conservation
- 6 Notable elm trees
- 7 The elm in art
- 8 The elm in mythology and literature
- 9 The elm in politics
- 10 The propagation of elms
- 11 Organisms associated with elm
- 12 See also
- 13 References
- 14 Monographs
- 15 Further reading
- 16 External links
'Sapporo Autumn Gold', IPP Monna Giovannella nursery, Antella, Florence
Wych elm (Ulmus glabra) leaves and seeds
Asymmetry of leaf, Slippery Elm U. rubra
Mature bark, Slippery Elm U. rubra
Flowers of the hybrid elm cultivar 'Columella'
Corky wings, Winged Elm U. alata
There are about 30 to 40 species of Ulmus (elm); the ambiguity in number results from difficulty in delineating species, owing to the ease of hybridization between them and the development of local seed-sterile vegetatively propagated microspecies in some areas, mainly in the field elm (Ulmus minor) group. Rackham describes Ulmus as the most difficult critical genus in the entire British flora, adding that 'species and varieties are a distinction in the human mind rather than a measured degree of genetic variation'. Eight species are endemic to North America, and a smaller number to Europe; the greatest diversity is found in Asia.
The classification adopted in the List of elm species, varieties, cultivars and hybrids is largely based on that established by Brummitt. A large number of synonyms have accumulated over the last three centuries; their currently accepted names can be found in the list List of elm Synonyms and Accepted Names.
The name Ulmus is the classical name for these trees, with the English name "elm" and many other European names derived from it.
The more abundant or better-known species of Ulmus include:
- Ulmus americana—American Elm, White Elm
- Ulmus davidiana—David Elm, Father David's Elm
- Ulmus davidiana var. japonica—Japanese Elm, Wilson's Elm
- Ulmus glabra—Wych Elm, Scots Elm
- Ulmus laevis—European White Elm, Fluttering Elm, Spreading Elm, (USA) Russian Elm
- Ulmus minor—Field Elm
- Ulmus parvifolia—Chinese Elm, Lacebark Elm
- Ulmus procera—English Elm, Atinian Elm
- Ulmus pumila—Siberian Elm
- Ulmus rubra—Slippery Elm, Red Elm
- Ulmus alata—Winged Elm, Wahoo
Pests and diseases
Dutch elm disease
Dutch elm disease (DED) devastated elms throughout Europe and much of North America in the second half of the 20th century. Owing to its geographical isolation and effective quarantine enforcement, Australia has so far remained unaffected by Dutch Elm Disease, as have the provinces of Alberta and British Columbia in western Canada.
DED is caused by a micro-fungus transmitted by two species of Scolytus elm-bark beetle which act as vectors. The disease affects all species of elm native to North America and Europe, but many Asiatic species have evolved anti-fungal genes and are resistant. Fungal spores, introduced into wounds in the tree caused by the beetles, invade the xylem or vascular system. The tree responds by producing tyloses, effectively blocking the flow from roots to leaves. Woodland trees in North America are not quite as susceptible to the disease because they usually lack the root-grafting of the urban elms and are somewhat more isolated from each other. In France, inoculation with the fungus of over three hundred clones of the European species failed to find a single variety possessed of any significant resistance.
The first, less aggressive strain of the disease fungus, Ophiostoma ulmi, arrived in Europe from the Far East in 1910, and was accidentally introduced to North America in 1928, but was steadily weakened by viruses and had all but disappeared in Europe by the 1940s. The second, far more virulent strain of the disease Ophiostoma novo-ulmi was identified in Europe in the late 1960s, and within a decade had killed over 20 million trees (approximately 75%) in the UK alone. Approximately three times more deadly, the origin of the new strain is again most likely the Far East; the hypothesis that it arose from a hybrid between the original O. ulmi and another strain endemic to the Himalaya, Ophiostoma himal-ulmi now discredited.
There is no sign of the current pandemic waning, and no evidence of a susceptibility of the fungus to a disease of its own caused by d-factors: naturally occurring virus-like agents that severely debilitated the original O. ulmi and reduced its sporulation.
Elm phloem necrosis
Elm phloem necrosis (elm yellows) is a disease of elm trees that is spread by leafhoppers or by root grafts. This very aggressive disease, with no known cure, occurs in the Eastern United States and southern Ontario in Canada. It is caused by phytoplasmas which infect the phloem (inner bark) of the tree. Infection and death of the phloem effectively girdles the tree and stops the flow of water and nutrients. The disease affects both wild-growing and cultivated trees.
Most serious of the elm pests is the elm leaf beetle Xanthogaleruca luteola, which can decimate foliage, although rarely with fatal results. The beetle was accidentally introduced to North America from Europe. Another unwelcome immigrant to North America is the Japanese beetle Popillia japonica. In both instances the beetles cause far more damage in North America owing to the absence of the predators present in their native lands. In Australia, introduced elm trees are sometimes used as foodplants by the larvae of hepialid moths of the genus Aenetus. These burrow horizontally into the trunk then vertically down.
Sapsucker woodpeckers have a great love of young elm trees.
Development of trees resistant to Dutch elm disease
Efforts to develop resistant cultivars began in the Netherlands in 1928 and continued, uninterrupted by World War II, until 1992. Similar programmes were initiated in North America (1937), Italy (1978), and Spain (1990s). Research has followed two paths:
Species and species cultivars
In North America, careful selection has produced a number of trees resistant not only to disease, but also to the droughts and extremely cold winters afflicting the continent. Research in the USA has concentrated on the American Elm U. americana, resulting in the release of highly resistant clones, notably the cultivars 'Valley Forge' and 'Jefferson'.
In Europe, it is the unique example of the European White Elm Ulmus laevis which has received the most attention. Whilst this elm has little innate resistance to Dutch elm disease, it is not favoured by the vector bark beetles and thus only becomes colonized and infected when there are no other choices, a rare situation in western Europe. Research in Spain has suggested that it may be the presence of a triterpene, alnulin, which makes the tree bark unattractive to the beetle species that spread the disease. However this possibility has not been conclusively proven.
Owing to their innate resistance to Dutch elm disease, Asiatic species have been crossed with European species, or with other Asiatic elms, to produce trees which are both highly resistant to disease and tolerant of native climates. After a number of false dawns in the 1970s, this approach has produced a range of reliable hybrid cultivars now commercially available in North America and Europe.
However, some of these cultivars, notably those with the Siberian Elm U. pumila in their ancestry, will probably have a comparatively small mature size and lack the forms for which the iconic American Elm and English Elm were prized. Moreover, several exported to northwestern Europe have proven unsuited to the maritime climate conditions there, notably because of their intolerance of anoxic conditions resulting from ponding on poorly drained soils in winter. Dutch hybridizations invariably included the Himalayan Elm U. wallichiana as a source of anti-fungal genes and have proven more tolerant of wet ground; they should also ultimately reach a greater size. A number of highly resistant Ulmus cultivars has been released since 2000, notably 'Morfeo'.
Cautions regarding novel cultivars
Elms take many decades to grow to maturity, and as the introduction of these disease-resistant cultivars is relatively recent, their long-term performance and ultimate size and form cannot be predicted with certainty. The National Elm Trial in North America, begun in 2005, is a large-scale scientific effort to assess strengths and weaknesses of the leading cultivars over a ten-year period.
Uses of elms in landscaping
From the 18th century to the early 20th century, elms were among the most widely planted ornamental trees in both Europe and North America. They were particularly popular as a street tree in avenue plantings in towns and cities, creating high-tunnelled effects. Their tolerance of air-pollution and the comparatively rapid decomposition of their leaf-litter in the fall were further advantages. In North America, the species most commonly planted was the American elm (Ulmus americana), which had unique properties that made it ideal for such use: rapid growth, adaptation to a broad range of climates and soils, strong wood, resistance to wind damage, and vase-like growth habit requiring minimal pruning. In Europe, the wych elm (U. glabra) and the smooth-leaved elm (U. minor var. minor) were the most widely planted in the countryside, with the former in northern areas including Scandinavia and northern Britain), and the latter further south. The hybrid between these two, Dutch elm (U. × hollandica), occurs naturally and was also commonly planted. In much of England, it was the English elm (Ulmus procera) which later came to dominate the horticultural landscape. Most commonly planted in hedgerows, the English elm sometimes occurred in densities of over 1000 per square kilometre. In Australia, large numbers of English elms, as well as other species and cultivars, were planted as ornamentals following their introduction in the 19th century. From about 1850 to 1920, the most prized small ornamental elm in parks and gardens was the Camperdown elm (Ulmus glabra 'Camperdownii'), a contorted weeping cultivar of the Wych Elm grafted onto a non-weeping elm trunk to give a wide, spreading and weeping fountain shape in large garden spaces.
During the 18th and 19th centuries, elm cultivars enjoyed much popularity as ornamentals in Europe by virtue of their rapid growth and variety of foliage and forms. This "belle époque" lasted until the First World War, when the consequences of hostilities, notably in Germany whence at least 40 cultivars originated, and the outbreak of Dutch elm disease saw the elm slide into horticultural decline. The devastation caused by the Second World War, and the demise in 1944 of the huge Späth nursery in Berlin, only accelerated the process. The outbreak of the new, three times more virulent, strain of Dutch elm disease Ophiostoma novo-ulmi in the late 1960s brought the tree to its nadir.
Since circa 1990 however, the elm has enjoyed a renaissance through the successful development in North America and Europe of cultivars highly resistant to the new disease. Consequently, the total number of named cultivars, ancient and modern, now exceeds 300, although many of the older clones, possibly over 120, have been lost to cultivation. Enthusiasm for the newer clones often remains low owing to the poor performance of earlier, supposedly disease-resistant Dutch trees released in the 1960s and 1970s. In the Netherlands, sales of elm cultivars slumped from over 56,000 in 1989 to just 6,800 in 2004, whilst in the UK, only four of the new American and European releases were commercially available in 2008.
Other uses of elms
Elm wood was valued for its interlocking grain, and consequent resistance to splitting, with significant uses in wagon wheel hubs, chair seats and coffins. The elm's wood bends well and distorts easily making it quite pliant. The often long, straight, trunks were favoured as a source of timber for keels in ship construction. Elm is also prized by bowyers; of the ancient bows found in Europe, a large portion of them are elm. During the Middle Ages elm was also used to make longbows if yew was unavailable.
The first written references to elm occur in the Linear B lists of military equipment at Knossos in the Mycenaean Period. Several of the chariots are of elm (« πτε-ρε-ϝα », pte-re-wa), and the lists twice mention wheels of elmwood. Hesiod says that ploughs in Ancient Greece were also made partly of elm.
The density of elm wood varies between species, but averages around 560 kg per cubic metre.
Elm wood is also resistant to decay when permanently wet, and hollowed trunks were widely used as water pipes during the medieval period in Europe. Elm was also used as piers in the construction of the original London Bridge. However this resistance to decay in water does not extend to ground contact.
The Romans, and more recently the Italians, used to plant elms in vineyards as supports for vines. Lopped at three metres, the elms' quick growth, twiggy lateral branches, light shade and root-suckering made them ideal trees for this purpose. The lopped branches were used for fodder and firewood. Ovid in his Amores characterizes the elm as "loving the vine": ulmus amat vitem, vitis non deserit ulmum (:the elm loves the vine, the vine does not desert the elm), and the ancients spoke of the "marriage" between elm and vine.
The mucilaginous inner bark of the Slippery Elm Ulmus rubra has long been used as a demulcent, and is still produced commercially for this purpose in the United States with approval for sale as a nutritional supplement by the U.S. Food and Drug Administration.
Elms also have a long history of cultivation for fodder, with the leafy branches cut to feed livestock. The practice continues today in the Himalaya, where it contributes to serious deforestation.
As fossil fuel resources diminish, increasing attention is being paid to trees as sources of energy. In Italy, the Istituto per la Protezione delle Piante is (2012) in the process of releasing to commerce very fast growing elm cultivars, able to increase in height by more than 2 m (6 ft) per annum.
Elm bark, cut into strips and boiled, sustained much of the rural population of Norway during the great famine of 1812. The seeds are particularly nutritious, comprising 45% crude protein, and less than 7% fibre by dry mass.
Elm has been listed as one of the 38 substances that are used to prepare Bach flower remedies, a kind of alternative medicine promoted for its effect on health. However according to Cancer Research UK, "there is no scientific evidence to prove that flower remedies can control, cure or prevent any type of disease, including cancer".
Genetic resource conservation
In 1997, a European Union elm project was initiated, its aim to coordinate the conservation of all the elm genetic resources of the member states and, among other things, to assess their resistance to Dutch elm disease. Accordingly, over 300 clones were selected and propagated for testing.
Notable elm trees
Many elm (Ulmus) trees of various kinds have attained great size or otherwise become particularly noteworthy; among these are the following.
American Elm Ulmus americana
- The Treaty Elm, Philadelphia, Pennsylvania. In what is now Penn Treaty Park, the founder of Pennsylvania, William Penn, is said to have entered into a treaty of peace in 1683 with the native Lenape Turtle Clan under a picturesque elm tree immortalized in a painting by Benjamin West. West made the tree, already a local landmark, famous by incorporating it into his painting after hearing legends (of unknown veracity) about the tree being the location of the treaty. No documentary evidence exists of any treaty Penn signed beneath a particular tree. On March 6, 1810 a great storm blew the tree down. Measurements taken at the time showed it to have a circumference of 24 feet (7.3 m), and its age was estimated to be 280 years. Wood from the tree was made into furniture, canes, walking sticks and various trinkets that Philadelphians kept as relics.
- The Washington Elm, Cambridge, Massachusetts. George Washington is said to have taken command of the American Continental Army under the Washington Elm in Cambridge on July 3, 1775. The tree survived until the 1920s and "was thought to be a survivor of the primeval forest". In 1872, a large branch fell from it and was used to construct a pulpit for a nearby church. The tree, an American White Elm, became a celebrated attraction, with its own plaque, a fence constructed around it and a road moved in order to help preserve it. The tree was cut down (or fell – sources differ) in October 1920 after an expert determined it was dead. The city of Cambridge had plans for it to be "carefully cut up and a piece sent to each state of the country and to the District of Columbia and Alaska," according to The Harvard Crimson. As late as the early 1930s, garden shops advertised that they had cuttings of the tree for sale, although the accuracy of the claims has been doubted. A Harvard "professor of plant anatomy" examined the tree rings days after the tree was felled and pronounced it between 204 and 210 years old, making it at most 62 years old when Washington took command of the troops at Cambridge. The tree would have been a little more than two feet in diameter (at 30 inches above ground) in 1773. In 1896, an alumnus of the University of Washington, obtained a rooted cutting of the Cambridge tree and sent it to Professor Edmund Meany at the university. The cutting was planted, cuttings were then taken from it, including one planted on February 18, 1932, the 200th anniversary of the birth of George Washington, for whom Washington state is named. That tree remains on the campus of the Washington State Capitol. Just to the west of the tree is a small elm from a cutting made in 1979.
- The Liberty Tree, an elm on Boston Common in Boston, Massachusetts, was a rallying point for the growing resistance to the rule of England over the American colonies.
- George Washington's Elm, Washington, D.C. George Washington supposedly had a favorite spot under an elm tree near the United States Capitol Building from which he would watch construction of the building. The elm stood near the Senate wing of the Capitol building until 1948.
- The Logan Elm stood near Circleville, Ohio. The 65-foot-tall (20 m) tree had a trunk circumference of 24 feet (7.3 m) and a crown spread of 180 feet (55 m). Weakened by Dutch Elm Disease, the tree died in 1964 from storm damage. The Logan Elm State Memorial commemorates the site and preserves various associated markers and monuments. According to tradition, Chief Logan of the Mingo tribe delivered a passionate speech at a peace-treaty meeting under this elm in 1774, said to be the most famous speech ever given by a Native American.
- "Herbie" in Yarmouth, Maine, stood by present-day East Main Street (Route 88) from 1793-2010. At 110 feet (34 m) in height, it was believed to be, between 1997 and the date of its felling, the oldest and tallest Ulmus americana in New England. The tree, which partially stood in the front yard of a private residence, also had a 20-foot (6.1 m) circumference and (until mid-2008) a 93-foot (28 m) crown spread. As of 2003, only twenty of Yarmouth's original 739 elms had survived Dutch elm disease. In August 2009 it was revealed that, after battling fifteen bouts of Dutch elm disease, the tree had lost, and on January 19, 2010 it was cut down.
- The Johnstown Elm, in Johnstown, NY, as of September, 2013, does not show any signs of Dutch elm disease. It has a circumference of 196 inches (~ 16 feet), a height of 85 feet, and a crown of 88 feet. It is growing in the front yard of a house in a small upstate city, and is probably over 200 years old. See photo at right.
- The Sauble Elm. With a girth of 24 feet 9 inches and a height of over 40 meters, the Sauble Elm, a white elm (Ulmus americana) which once grew beside the banks of the Sauble River between the towns of Hepworth and Sauble Beach in the county of Bruce in the province of Ontario, was one of the largest "wild" elms in North America. The tree succumbed to Dutch Elm Disease and was felled in 1968. A ring count established that it had begun life in the year 1701.
- The Philipsburg Elm, Philipsburg, Quebec, was a 280 year-old 30 meter Ulmus americana, dubbed "the king of elms". It was cut down in March 2009 after death from Dutch Elm Disease.
- The Great Elm on Boston Common, supposed to have been in existence before the settlement of Boston, at the time of its destruction by the storm of the 15th of February 1876 measured 22 ft (6.7 m). in circumference.
- "Elmo", Brown University, Providence, Rhode Island, a large elm that "once defined the Thayer Street entrance to Brown’s new Watson Institute for International Studies," contracted Dutch Elm disease and was torn down in December 2003, according to a campus news release. The tree "was thought to have been between 80 and 100 years old. Wood from the tree, one of the largest on campus, was used in various student art projects.
- The Tabletop Elm in Provo, Utah. Next to the USU Utah County Extension Office resides possibly a one-of-a-kind elm tree. Officially it is a specimen of Ulmus americana, but is unusual because it grows sideways, making it a "tabletop" elm tree. The tree was planted in 1927, and currently its several branches are supported by specialized braces to allow movement and growth. Every fall seven dump truck loads are required to remove all the leaves.
- The Association Island Elm, New York State. The General Electric think tank organization, the Elfun Society, founded in 1928 at Association Island in the Thousand Islands area of northern New York state, is named after a famous elm tree on the 65-acre (260,000 m2) isle. The tree died in the 1970s, but it survives in the elm tree logo still used by Elfun.
- New Haven, Connecticut, had the first public tree planting program in America, producing a canopy of mature trees (including some large elms) that gave New Haven the nickname "The Elm City". This later gave rise to the Yale song, Neath the Elms.
Wych Elm Ulmus glabra
- "Joe Pullen's Tree", a wych elm (Ulmus glabra) in Oxford, was planted in about 1700 by the Rev. Josiah Pullen, vice president of Magdalen Hall. Josiah Pullen "used to Walk to that place every day, sometimes twice a day", according to diarist Thomas Hearne. The famous essayist Richard Steele (1672–1729) said his regular walks as an undergraduate to the elm with Pullen helped him to reach a "florid old age". The elm became famous at Oxford and its fame grew with its age. In November 1795, Gentleman's Magazine reported that "Joe Pullen, the famous elm, upon Headington hills, had one of its large branches torn off and carried to a great distance." When new parliamentary district boundaries were drawn after the Reform Act 1832, the tree was named as a landmark helping to mark the boundary of the Parliamentary Borough of Oxford. In early 1847, the owner of the property arranged to have the tree torn down, and work started on it before protests put an end to the plan. By 1892, however, rot had set in, and the tree was torn down to its (large and tall) "stump". Early in the morning of October 13, 1909, vandals set fire to the stump. A plaque was soon after installed on the side wall of Davenport House in Cuckoo Lane, marking the spot. It reads: Near this spot stood the famous elm planted by the Rev. Josiah Pullen about 1680 and known as Jo Pullen's Tree. Destroyed by fire on 13 October 1909.
Dutch Elm Ulmus × hollandica
- The Great Saling Elm. With a girth of 6.86 m and a height of 40 m, the elm on Great Saling Green, Great Saling, near Braintree, Essex, identified by R. H. Richens (1983) as an Ulmus × hollandica hybrid, was reputed to be the largest elm in England, before succumbing to Dutch Elm Disease in the 1980s. A photograph of the tree can be found (plate 402) in Elwes & Henry's Trees of Great Britain & Ireland, published in 1913, wherein it is identified as U. nitens (U. minor subsp. minor).
- The Oudemanhuispoort Elm. 34.6 m tall and 4.4 m in girth, this Ulmus × hollandica 'Belgica' in Oudemanhuispoort, Amsterdam, planted in 1895, is the largest elm in the Netherlands.
- "The MooCoo Tree,", in Athens, Georgia, stands in front of Theta Chi Fraternity at the University of Georgia; it is one of the few Dutch Elm (Ulmus × hollandica) trees in North America east of the Mississippi. Students are known to engage in the "MooCoo Challenge," which consists climbing into the Elm and consuming twelve beers before coming down.
Field Elm Ulmus minor
- The Metaxades Elm. An ancient Field Elm (Ulmus minor) stood until recently in the village square of Metaxades, Thrace, Greece. Having abandoned their original village in 1286 after cholera outbreaks, the villagers re-founded it in the hills where a young elm grew beside a spring. The elm (reputedly the original) and fountain were until recently the focal-point of the village.
- The Biscarrosse Elm. Reputedly planted in 1350, this Field Elm (Ulmus minor) survived in the centre of Biscarrosse in the Landes region of south-west France until 2010, when it finally succumbed to Dutch elm disease. Its habit of producing a circle of white epicormic leaves on the bole every spring gave rise to a local legend. The 'white wreath' was said to be related to the public humiliation in 1450 and death beneath the tree of a local girl wrongly accused of adultery.
- The Elm of Bettange. Reputedly planted in 1593, this Field Elm (Ulmus minor) in the village of Bettange in the Moselle region of France is now a wreck  In so far as measurements can be taken of its ruined bole, its girth has been estimated at over 6 m.
- “L’Olmo di Lando”, known in Italy as “L’Olmo Bello” (:The Beautiful Elm). This shapely, open-grown Field Elm (Ulmus minor) stood at Ostra near Senigallia in the Italian Marches, where its "montagna di verde" (:mountain of greenery) attracted many admirers, who bought its portrait in postcards. It had a 110 m crown-circumference, a 35 m crown-diameter, and a 6,30 m bole-girth at ground level. It was felled in 1935 when it lost its looks and threatened to damage those of the people standing beneath it. A ring-count established that it was over 400 years old.
- The Mergozzo Elm. A four hundred year-old Ulmus minor, 5.55 metres in girth, survives in the town of Mergozzo in Piedmont. 'L'olmo di Mergozzo', like its French counterparts 'l'orme de Biscarosse' and 'l’orme de Bettange', is hollowed out by age, its life prolonged by pollarding.
- The "bleeding" elms of Saint Nicholas the Martyr, Thessaly. In the grounds of the Greek Orthodox monastery of Saint Nicholas near Vounaina (Βούναινα), Thessaly, built on the site of the slaughter, c.720, by maurauding Avars, of the Byzantine ascetic St Nicholas the Martyr (Άγιος Νικόλαος ο εν Βουνένοις) and his followers, stands a group of revered elms that in May on the anniversary of the martyrdom "bleed" a purplish fluid, believed by many of the Orthodox faith to have miraculous healing properties. The phenomenon, possibly related to wetwood, attracts large crowds to the monastery every year.
English Elm Ulmus procera
- The Preston Twins in Preston Park, Brighton, England, are the two oldest English elms in the world. Both trees are aged over 400 years and exceed 6 metres in girth. They have been regularly pollarded for many years and both trunks are hollow. The smaller, nearer the A23 London Road, can be entered from the east side; two people can stand comfortably inside it. The trees may be associated with the Medieval Manorial Scrolls kept in the County Records Office in Lewes.
Other, unidentified elms
- The Langton Elm in Sherwood Forest, Nottinghamshire, was a large elm tree that "was for a long time so remarkable as to have a special keeper", according to a book published in 1881.
The elm in art
Many artists have admired elms for the ease and grace of their branching and foliage, and have painted them with sensitivity. Elms are a recurring element in the landscapes and studies of, for example, John Constable, Ferdinand Georg Waldmüller, Frederick Childe Hassam, Karel Klinkenberg, and George Inness.
John Constable, 'The Cornfield'  (Ulmus × hollandica )
Constable, 'Salisbury Cathedral from the Bishop's Garden' [1823 version] (Ulmus × hollandica )
Jacob George Strutt, Elms at Mongewell, Oxfordshire  (Ulmus procera)
Ferdinand Georg Waldmüller, 'Alte Ulmen im Prater' (:Old Elms in Prater) 
[unknown artist] The American Elm  (Ulmus americana)
Frederick Childe Hassam, 'Champs Elysées, Paris'  (Ulmus × hollandica, 'orme femelle' )
Frederick Childe Hassam, 'Washington Arch, Spring'  (Ulmus americana)
Frederick Childe Hassam, 'Church at Old Lyme'  (Ulmus americana)
Frederick Childe Hassam, 'Church at Old Lyme'  (Ulmus americana)
George Inness, 'Old Elm at Medfield' (Ulmus americana)
Unknown artist, 'The Cam near Trinity College, Cambridge', England (Ulmus minor)
The elm in mythology and literature
The first reference in literature to elms occurs in the Iliad. When Eetion, father of Andromache, is killed by Achilles during the Trojan War, the Mountain Nymphs plant elms on his tomb («περὶ δὲ πτελέoι εφύτεψαν νύμφαι ὀρεστιάδες, κoῦραι Διὸς αἰγιόχoιo»). Also in the Iliad, when the River Scamander, indignant at the sight of so many corpses in his water, overflows and threatens to drown Achilles, the latter grasps a branch of a great elm in an attempt to save himself («ὁ δὲ πτελέην ἕλε χερσὶν εὐφυέα μεγάλην».
The Nymphs also planted elms on the tomb in the Thracian Chersonese of “great-hearted Protesilaus’’ («μεγάθυμου Πρωτεσιλάου»), the first Greek to fall in the Trojan War. These elms grew to be the tallest in the known world; but when their topmost branches saw far off the ruins of Troy, they immediately withered, so great still was the bitterness of the hero buried below, who had been loved by Laodamia and slain by Hector. The story is the subject of a poem by Antiphilus of Byzantium (1st century A.D.) in the Palatine Anthology:
- Θεσσαλὲ Πρωτεσίλαε, σὲ μὲν πολὺς ᾄσεται αἰών,
- Tρoίᾳ ὀφειλoμένoυ πτώματος ἀρξάμενoν•
- σᾶμα δὲ τοι πτελέῃσι συνηρεφὲς ἀμφικoμεῦση
- Nύμφαι, ἀπεχθoμένης Ἰλίoυ ἀντιπέρας.
- Δένδρα δὲ δυσμήνιτα, καὶ ἤν ποτε τεῖχoς ἴδωσι
- Tρώϊον, αὐαλέην φυλλοχoεῦντι κόμην.
- ὅσσoς ἐν ἡρώεσσι τότ᾽ ἦν χόλoς, oὗ μέρoς ἀκμὴν
- ἐχθρὸν ἐν ἀψύχoις σώζεται ἀκρέμoσιν.
- [:Thessalian Protesilaos, a long age shall sing your praises,
- Of the destined dead at Troy the first;
- Your tomb with thick-foliaged elms they covered,
- The nymphs, across the water from hated Ilion.
- Trees full of anger; and whenever that wall they see,
- Of Troy, the leaves in their upper crown wither and fall.
- So great in the heroes was the bitterness then, some of which still
- Remembers, hostile, in the soulless upper branches.]
Elms occur often in Pastoral Poetry, where they symbolise the idyllic life, their shade being mentioned as a place of special coolness and peace. In the first Idyll of Theocritus, for example, the goat-herd invites the shepherd to sit “here beneath the elm” («δεῦρ’ ὑπὸ τὰν πτελέαν») and sing. Beside elms Theocritus places “the sacred water” («το ἱερὸν ὕδωρ») of the Springs of the Nymphs and the shrines to the nymphs.
Aside from references literal and metaphorical to the elm and vine theme, the tree occurs in Latin literature in the Elm of Dreams in the Aeneid. When the Sibyl of Cumae leads Aeneas down to the Underworld, one of the sights is the Stygian Elm:
- In medio ramos annosaque bracchia pandit
- ulmus opaca, ingens, quam sedem somnia vulgo
- uana tenere ferunt, foliisque sub omnibus haerent.
- [:Spreads in the midst her boughs and agéd arms
- an elm, huge, shadowy, where vain dreams, 'tis said,
- are wont to roost them, under every leaf close-clinging.]
Virgil refers to a Roman superstition (vulgo) that elms were trees of ill-omen because their fruit seemed to be of no value. It has been noted  that two elm-motifs have arisen from classical literature: (1) the 'Paradisal Elm' motif, arising from pastoral idylls and the elm-and-vine theme, and (2) the 'Elm and Death' motif, perhaps arising from Homer's commemorative elms and Virgil's Stygian Elm. Many references to elm in European literature from the Renaissance onwards fit into one or other of these categories.
There are two examples of pteleogenesis (:birth from elms) in world myths. In Germanic and Scandinavian mythology the first woman, Embla, was fashioned from an elm, while in Japanese mythology Kamuy Fuchi, the chief goddess of the Ainu people, "was born from an elm impregnated by the Possessor of the Heavens".
The elm occurs frequently in English literature, one of the best known instances being in Shakespeare's A Midsummer Night's Dream, where Titania, Queen of the Fairies, addresses her beloved Nick Bottom using an elm-simile. Here, as often in the elm-and-vine motif, the elm is a masculine symbol:
- Sleep thou, and I will wind thee in my arms.
- ... the female Ivy so
- Enrings the barky fingers of the Elm.
- O, how I love thee! how I dote on thee! 
Another of the most famous kisses in English literature, that of Paul and Helen at the start of Forster's Howards End, is stolen beneath a great wych elm.
The Elm Tree is also referenced in children's literature. An Elm Tree and Three Sisters is a children's book about three young sisters that plant a small elm tree in their backyard. Throughout the years, the sisters begin to realize that the elm tree becomes an integral part of their lives. The sisters see that the elm tree has been with them through many important milestones through life and they grow old with the tree.
The elm in politics
In politics the elm is associated with revolutions. In England after the Glorious Revolution of 1688, the final victory of parliamentarians over monarchists, and the arrival from Holland, with William & Mary, of the 'Dutch Elm' hybrid, planting of this cultivar became a fashion among enthusiasts of the new political order.
In the American Revolution 'The Liberty Tree' was an American white elm in Boston, Massachusetts, in front of which, from 1765, the first resistance meetings were held against British attempts to tax the American colonists without democratic representation. When the British, knowing that the tree was a symbol of rebellion, felled it in 1775, the Americans took to widespread 'Liberty Elm' planting, and sewed elm symbols on to their revolutionary flags. Elm-planting by American Presidents later became something of a tradition.
In the French Revolution, too, Les arbres de la liberté (:Liberty Trees), often elms, were planted as symbols of revolutionary hopes - the first in Vienne, Isère, in 1790, by a priest inspired by the Boston elm. L'Orme de La Madeleine (:the Elm of La Madeleine), Faycelles, Département de Lot, planted around 1790 and surviving to this day, was a case in point. By contrast, a famous Parisian elm associated with the Ancien Régime, L’Orme de Saint-Gervais in the Place St-Gervais, was felled by the revolutionaries; church authorities planted a new elm in its place in 1846, and an early 20th-century elm stands on the site today. Premier Lionel Jospin, obliged by tradition to plant a tree in the garden of the Hôtel Matignon, the official residence and workplace of Prime Ministers of France, insisted on planting an elm, so-called 'tree of the Left', choosing the new disease-resistant hybrid 'Clone 762' ('Ulmus 'Wanoux' (Vada)).
Liberty Elms were also planted in other countries in Europe to celebrate their revolutions, an example being L'Olmo di Montepaone, L'Albero della Libertà (:the Elm of Montepaone, Liberty Tree) in Montepaone, Calabria, planted in 1799 to commemorate the founding of the democratic Parthenopean Republic, and surviving till it was brought down by a recent storm (it has since been cloned and 'replanted'). And after the Greek Revolution of 1821-32, a thousand young elms were brought to Athens from Missolonghi, "Sacred City of the Struggle" against the Turks and scene of Lord Byron's death, and planted in 1839-40 in the National Garden. In Thessaloniki a more recent Libery Elm, «Η Φτελιά της 25ης Μαρτίου» (:The Elm of the 25th March), the oldest elm in the city, still stands at the beginning of 25th March Street (Οδός 25ης Μαρτίου), date of the beginning of the 1821 revolution. In an ironic development, wild elms have spread and taken over the grounds of the abandoned Greek royal summer palace at Tatoi in Attica.
Planting a Liberty Tree (un arbre de la liberté) during the French Revolution. Jean-Baptiste Lesueur, 1790
President George W. Bush and Laura Bush planting a disease-resistant 'Jefferson' Elm before the White House, 2006
The propagation of elms
Elm propagation methods vary according to elm type and location, and the plantsman’s needs. Native species in their natural setting, such as wych elm and European White Elm in central and northern Europe and Field Elm in southern Europe, set viable seed in ‘favourable’ seasons. Optimal conditions occur after a late warm spring. Native species may be propagated by seed. After pollination, seeds of spring-flowering elms ripen and fall at the start of summer (June); they remain viable for only a few days. They are planted in sandy potting-soil at a depth of one centimetre. Slow-germinating American Elm will remain dormant until the second season. Seeds from autumn-flowering elms ripen in the Fall and germinate in the spring. Since elms may hybridize within and between species, seed-propagation entails a hybridisation risk. In unfavourable seasons elm seeds are usually sterile. Elms outside their natural range, such as Ulmus procera in England, and elms unable to pollinate because pollen-sources are genetically identical, are sterile and are propagated by vegetative reproduction. Vegetative reproduction is also used to produce genetically identical elms (clones). Methods include the winter transplanting of root-suckers; taking hardwood cuttings from vigorous one-year-old shoots in late winter, taking root-cuttings in early spring; taking softwood cuttings in early summer; grafting; layering; and micropropagation. A bottom heat of 18 degrees  and humid conditions are maintained for hard- and softwood cuttings. The transplanting of root-suckers remains the easiest and commonest propagation-method for European Field Elm and its hybrids. For 'specimen' urban elms, grafting to wych-elm root-stock may be used to eliminate suckering or to ensure stronger root-growth. The mutant-elm cultivars are usually grafted, the ‘weeping’ elms Camperdown Elm and Ulmus glabra 'Horizontalis' at 2 – 3 m, the dwarf elms Ulmus 'Nana' and Ulmus × hollandica 'Jacqueline Hillier' at ground level. Since the Siberian Elm is drought-tolerant, in dry countries new varieties of elm are often root-grafted on this species.
Seedling of wych elm Ulmus glabra (photograph: Mihailo Grbić)
Root cuttings of Ulmus 'Dodoens' (photograph: Mihailo Grbić)
Mutant variegated Smooth-leafed Elm graft (photograph: Mihailo Grbić)
Organisms associated with elm
'Pouch' leaf-gall on elm leaf (aphid Tetraneura ulmi), Netherlands.
'Cockscomb' leaf-galls (aphid Colopha compressa), Poland.
'Bladder' leaf-galls on elm leaves (aphid Eriosoma lanuginosum), Italy.
'Bladder' leaf-galls on a narrow-leaved elm (aphid Eriosoma lanuginosum), Italy.
Rare white-letter hairstreak butterfly, Satyrium w-album, on an Ulmus 'Nanguen', Sweden. The caterpillars feed exclusively on elm-leaves.
Egg of Satyrium w-album near flower-bud of an elm.
Elm-bark beetle Scolytus multistriatus (size: 2-3 mm), a vector for Dutch Elm Disease
Scolytus multistriatus 'galleries' under elm-bark.
Elm-leaf beetle Xanthogaleruca luteola, which causes serious damage to elm foliage.
Xanthogaleruca luteola: caterpillar on elm-leaf, Germany.
Elm-leaf damage caused by Xanthogaleruca luteola, Germany.
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