78-547: Elms are trees in the genus Ulmus . Elms or ELMS may refer to: Elm See Elms are deciduous and semi-deciduous trees comprising the genus Ulmus in the family Ulmaceae . They are distributed over most of the Northern Hemisphere, inhabiting the temperate and tropical - montane regions of North America and Eurasia, presently ranging southward in the Middle East to Lebanon and Israel, and across
156-407: A microfungus dispersed by bark beetles . In response, disease-resistant cultivars have been developed, capable of restoring the elm to forestry and landscaping . The genus is hermaphroditic , having apetalous perfect flowers which are wind-pollinated. Elm leaves are alternate, with simple, single- or, most commonly, doubly serrate margins, usually asymmetric at the base and acuminate at
234-449: A consequence of Dutch elm disease and/or other factors: NB: 'Exoniensis', Exeter Elm , has traditionally been classified as a form of U. glabra , but its identity is now a matter of contention. U. glabra hybridises naturally with U. minor , producing elms of the Ulmus × hollandica group, from which have arisen a number of cultivars: However, hybrids of U. glabra and U. pumila ,
312-661: A few days. They are planted in sandy potting soil at a depth of 1 cm, and germinate in three weeks. 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 English elm U. minor 'Atinia' , and elms unable to pollinate because pollen sources are genetically identical, are sterile and are propagated by vegetative reproduction . Vegetative reproduction
390-468: A result, the population of American elms planted on the Mall and its surrounding areas has remained intact for more than 80 years. Elm wood is valued for its interlocking grain, and consequent resistance to splitting, with significant uses in wagon -wheel hubs, chair seats, and coffins . The bodies of Japanese Taiko drums are often cut from the wood of old elm trees, as the wood's resistance to splitting
468-523: A single variety that possessed of any significant resistance. The first, less aggressive strain of the disease fungus, Ophiostoma ulmi , arrived in Europe from Asia in 1910, and was accidentally introduced to North America in 1928. It was steadily weakened by viruses in Europe and had all but disappeared by the 1940s. However, the disease had a much greater and longer-lasting impact in North America, owing to
546-599: Is a nationwide trial to assess strengths and weaknesses of the 19 leading cultivars raised in the US over a 10-year period; European cultivars have been excluded. Meanwhile, in Europe, American and European cultivars are being assessed in field trials started in 2000 by the UK charity Butterfly Conservation . The oldest American elm trees in New York City's Central Park were planted in the 1860s by Frederick Law Olmsted , making them among
624-453: 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 , but this resistance to decay in water does not extend to ground contact. The Romans, and more recently the Italians, planted elms in vineyards as supports for vines. Lopped at 3 m,
702-480: 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 ; ground and air layering ; and micropropagation . A bottom heat of 18 °C and humid conditions are maintained for hard- and softwood cuttings. The transplanting of root suckers remains
780-569: 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 year. 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, containing 45% crude protein, and less than 7% fibre by dry mass. Elm has been listed as one of
858-762: Is believed to be the tree (girth 5.2 m) in the former grounds of Duddingston House , now Duddingston Golf Course. Other notable specimens in Edinburgh are to be found in Learmonth Gardens and The Meadows . In Europe, a large tree planted in 1620 grows at Bergemolo, 5 km south of Demonte in Piedmont , Italy (bole-girth 6.2 m, 2.0 m DBH, height 26 m., 2008). Other ancient specimens grow at Styria, in Austria, and at Grenzhammer, Germany (see Gallery). In 1998, over 700 healthy, mature trees were discovered on
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#1732838368513936-474: Is by seed alone. The tree is notable for its very tough, supple young shoots, which are always without the corky ridges or 'wings' characteristic of many elms. The alternate leaves are deciduous, 6–17 cm long by 3–12 cm broad, usually obovate with an asymmetric base, the lobe often completely covering the short (<5 mm) petiole ; the upper surface is rough. Leaves on juvenile or shade-grown shoots sometimes have three or more lobes near
1014-401: Is caused by phytoplasmas that 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. Occasionally, cutting the infected tree before the disease completely establishes itself and cleanup and prompt disposal of infected matter has resulted in
1092-479: Is highly desired for nailing the skins to them, and a set of three or more is often cut from the same tree. The elm's wood bends well and distorts easily. 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 are elm. During the Middle Ages , elm was also used to make longbows if yew
1170-546: Is invariably carried by the female parent. Some of these cultivars, notably those with the Siberian elm ( Ulmus pumila ) in their ancestry, 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
1248-453: Is less favoured as a host by the elm bark beetles, which act as vectors. Research in Spain has indicated the presence of a triterpene , alnulin , rendering the tree bark less attractive to the beetle than the field elm , though at 87 μg/g dried bark, its concentration is not as effective as in Ulmus laevis (200 μg/g). Moreover, once the tree is dying, its bark is quickly colonized by
1326-491: Is no longer monitored. Sapsucker woodpeckers have a great love of young elm trees. One of the earliest of ornamental elms was the ball-headed graft narvan elm, Ulmus minor 'Umbraculifera' , cultivated from time immemorial in Persia as a shade tree and widely planted in cities through much of south-west and central Asia. From the 18th century to the early 20th century, elms, whether species, hybrids, or cultivars , were among
1404-499: Is not favoured by the vector bark beetles. Thus it becomes colonized and infected only when no other elms are available, 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. This possibility, though, has not been conclusively proven. More recently, field elms Ulmus minor highly resistant to DED have been discovered in Spain, and form
1482-622: Is often listed as a regional form of Ulmus glabra . The word "wych" (also spelled "witch") comes from the Old English wice , meaning pliant or supple, which also gives definition to wicker and weak. Jacob George Strutt 's 1822 book, Sylva Britannica attests that the Wych Elm was sometimes referred to as the "Wych Hazel", a name now applied to the unrelated species Hamamelis , commonly called "wych hazels". Some botanists, notably Lindquist (1931), have proposed two subspecies : Much overlap
1560-453: Is seen between populations with these characters, and the distinction may owe to environmental influence, rather than genetic variation; the subspecies are not accepted by Flora Europaea . The type sometimes reaches heights of 40 m (130 ft), typically with a broad crown where open-grown, supported by a short bole up to 2 m (6.6 ft) diameter at breast height (DBH). Normally, root suckers are not seen; natural reproduction
1638-505: Is thought to have originated in Asia. The two subspecies have now hybridized in Europe where their ranges have overlapped. The hypothesis that O. novo-ulmi arose from a hybrid of the original O. ulmi and another strain endemic to the Himalayas , Ophiostoma himal-ulmi , is now discredited. No sign indicates the current pandemic is waning, and no evidence has been found of a susceptibility of
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#17328383685131716-573: The American elm in excess of 30 m (100 ft), often with a forked trunk creating a vase profile. 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 Ulmus field elm ( Ulmus minor ) group. Oliver Rackham describes Ulmus as
1794-580: 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
1872-592: The Siberian elm is drought tolerant, in dry countries, new varieties of elm are often root-grafted onto this species. Dutch elm disease (DED) devastated elms throughout Europe and much of North America in the second half of the 20th century. It derives its name "Dutch" from the first description of the disease and its cause in the 1920s by Dutch botanists Bea Schwarz and Christina Johanna Buisman . Owing to its geographical isolation and effective quarantine enforcement, Australia has so far remained unaffected by DED, as have
1950-458: The apex . The fruit is a round wind-dispersed samara flushed with chlorophyll , facilitating photosynthesis before the leaves emerge. The samarae are very light, those of British elms numbering around 50,000 to the pound (454 g ). (Very rarely anomalous samarae occur with more than two wings. ) All species are tolerant of a wide range of soils and pH levels but, with few exceptions, demand good drainage. The elm tree can grow to great height,
2028-461: The fungus Phoma , which radically reduces the amount of bark available for the beetle to breed on. In European trials, clones of apparently resistant trees were inoculated with the pathogen, causing 85 – 100% wilting, resulting in 68% mortality by the following year. DNA analysis by Cemagref (now Irstea ) in France has determined the genetic diversity within the species is very limited, making
2106-1129: The wych elm or Scots elm , has the widest range of the European elm species, from Ireland eastwards to the Ural Mountains , and from the Arctic Circle south to the mountains of the Peloponnese and Sicily , where the species reaches its southern limit in Europe; it is also found in Iran. A large deciduous tree, it is essentially a montane species, growing at elevations up to 1,500 m (4,900 ft), preferring sites with moist soils and high humidity. The tree can form pure forests in Scandinavia and occurs as far north as latitude 67°N at Beiarn Municipality in Norway. It has been successfully introduced as far north as Tromsø and Alta in northern Norway (70°N). It has also been successfully introduced to Narsarsuaq , near
2184-467: The 19th century, while in northern Japan Japanese elm ( U. davidiana var. japonica ) was widely planted as a street tree. From about 1850 to 1920, the most prized small ornamental elm in parks and gardens was the 'Camperdown' elm ( U. glabra 'Camperdownii') , a contorted, weeping cultivar of the wych elm grafted on to a nonweeping elm trunk to give a wide, spreading, and weeping fountain shape in large garden spaces. In northern Europe, elms were among
2262-654: The 38 substances that are used to prepare Bach flower remedies , a kind of alternative medicine . Chinese elm ( Ulmus parvifolia ) is a popular choice for bonsai owing to its tolerance of severe pruning. 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. Many elm trees of various kinds have attained great size or otherwise become particularly noteworthy. Many artists have admired elms for
2340-673: The American elm ( U. americana ), resulting in the release of DED-resistant clones, notably the cultivars 'Valley Forge' and 'Jefferson' . Much work has also been done into the selection of disease-resistant Asiatic species and cultivars. In 1993, Mariam B. Sticklen and James L. Sherald reported the results of experiments funded by the US National Park Service and conducted at Michigan State University in East Lansing that were designed to apply genetic engineering techniques to
2418-563: The Elms', 'leaman' being the plural form of leam or lem, 'elm'. Closely related species, such as Bergmann's elm U. bergmanniana and Manchurian elm U. laciniata , native to northeast Asia , were once sometimes included in U. glabra ; another close relative is the Himalayan or Kashmir elm U. wallichiana . Conversely, Ulmus elliptica from the Caucasus, considered a species by some authorities,
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2496-724: The Equator in the Far East into Indonesia. Elms are components of many kinds of natural forests . Moreover, 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
2574-569: The Himalayan elm ( Ulmus wallichiana ) as a source of antifungal genes and have proven more tolerant of wet ground; they should also ultimately reach a greater size. However, the susceptibility of the cultivar 'Lobel', used as a control in Italian trials, to elm yellows has now (2014) raised a question mark over all the Dutch clones. Several highly resistant Ulmus cultivars have been released since 2000 by
2652-645: The Institute of Plant Protection in Florence, most commonly featuring crosses of the Dutch cultivar 'Plantijn' with the Siberian elm to produce resistant trees better adapted to the Mediterranean climate. 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,
2730-461: The Italian elm breeding programme circa 2000. Hybrids with U. glabra in their ancestry have featured strongly in recent artificial hybridization experiments in Europe, notably at Wageningen in the Netherlands , and a number of hybrid cultivars have been commercially released since 1960. The earlier trees were raised in response to the initial Dutch elm disease pandemic that afflicted Europe after
2808-681: The List of elm species 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 of Elm synonyms and accepted names . Botanists who study elms and argue over elm identification and classification are called "pteleologists", from the Greek πτελέα (elm). As part of the suborder urticalean rosids , they are distantly related to cannabis , mulberries , figs , hops , and nettles . Elm propagation methods vary according to elm type and location, and
2886-532: 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 (1986). Research has followed two paths: In North America, careful selection has produced a number of trees resistant not only to DED, but also to the droughts and cold winters that occur on the continent. Research in the United States has concentrated on
2964-527: The Siberian elm, have not been observed in the field and only achieved in the laboratory, though the ranges of the two species, the latter introduced by man, overlap in parts of Southern Europe, notably Spain. A crossing in Russia of U. glabra and U. pumila produced the hybrid named Ulmus × arbuscula ; a similar crossing was cloned ('FL025') by the Istituto per la Protezione delle Piante (IPP), Florence, as part of
3042-553: 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 (first century AD) in the Palatine Anthology : Wych elm Ulmus glabra Hudson ,
3120-508: The absence of the predators in their native lands. In Australia, introduced elm trees are sometimes used as food plants by the larvae of hepialid moths of the genus Aenetus . These burrow horizontally into the trunk then vertically down. Circa 2000, the Asian Zig-zag sawfly Aproceros leucopoda appeared in Europe and North America, although in England, its impact has been minimal and it
3198-664: The age of three, the infant goddess Artemis practised her newly acquired silver bow and arrows, made for her by Hephaestus and the Cyclopes , by shooting first at an elm, then at an oak, before turning her aim on a wild animal: 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 ("περί δὲ πτελέας ἐφύτευσαν νύμφαι ὀρεστιάδες, κoῦραι Διὸς αἰγιόχoιo"). Also in
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3276-444: The apex. The perfect hermaphrodite flowers appear before the leaves in early spring, produced in clusters of 10–20; they are 4 mm across on 10 mm long stems, and being wind-pollinated, are apetalous . The fruit is a winged samara 20 mm long and 15 mm broad, with a single, round, 6 mm seed in the centre, maturing in late spring. While the species is highly susceptible to Dutch elm disease , it
3354-451: The basis of a major breeding programme. Owing to their innate resistance to DED, Asiatic species have been crossed with European species, or with other Asiatic elms, to produce trees that 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. Disease resistance
3432-428: 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 300 clones of the European species failed to find
3510-537: The chances of a resistant tree evolving rather remote. A 300-year-old example growing in Grenzhammer , Ilmenau has allegedly been scientifically proven to be resistant to Dutch elm disease. The Swedish Forest Tree Breeding Association at Källstorp produced triploid and tetraploid forms of the tree, but these proved no more resistant to Dutch elm disease than the normal diploid form. In trials conducted in Italy,
3588-401: The characteristic fissures and markings of 'burr elm' wood. Bosses fringed with shoots are burrs, whereas unfringed bosses are burls. In 18th century France, the inner bark of Ulmus glabra , orme pyramidale , had a brief reputation as a panacea ; "it was taken as a powder, as an extract, as an elixir, even in baths. It was good for the nerves, the chest, the stomach — what can I say? — it
3666-642: The countryside, the former in northern areas including Scandinavia and northern Britain , the latter further south. The hybrid between these two, Dutch elm ( U. × hollandica ) , occurs naturally and was also commonly planted. In much of England, the English elm later came to dominate the horticultural landscape. Most commonly planted in hedgerows, it sometimes occurred in densities over 1000/km . In south-eastern Australia and New Zealand, large numbers of English and Dutch elms, as well as other species and cultivars, were planted as ornamentals following their introduction in
3744-566: The development of DED-resistant strains of American elm trees. In 2007, A. E. Newhouse and F. Schrodt of the State University of New York College of Environmental Science and Forestry in Syracuse reported that young transgenic American elm trees had shown reduced DED symptoms and normal mycorrhizal colonization. In Europe, the European white elm ( U. laevis ) has received much attention. While this elm has little innate resistance to DED, it
3822-511: 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 . In Greek mythology, the nymph Ptelea (Πτελέα, Elm) was one of the eight hamadryads , nymphs of the forest and daughters of Oxylos and Hamadryas. In his Hymn to Artemis , poet Callimachus (third century BC) tells how, at
3900-422: The easiest most and common propagation method for European field elm and its hybrids. For specimen urban elms, grafting to wych-elm rootstock may be used to eliminate suckering or to ensure stronger root growth. The mutant-elm cultivars are usually grafted, the "weeping" elms 'Camperdown' and 'Horizontalis' at 2–3 m (7–10 ft), the dwarf cultivars 'Nana' and 'Jacqueline Hillier' at ground level. Since
3978-451: 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
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#17328383685134056-566: The few trees tolerant of saline deposits from sea spray, which can cause "salt-burning" and die-back. This tolerance made elms reliable both as shelterbelt trees exposed to sea wind, in particular along the coastlines of southern and western Britain and in the Low Countries, and as trees for coastal towns and cities. This belle époque lasted until the First World War , when the elm began its slide into horticultural decline. The impact of
4134-538: 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 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 , southern Ontario in Canada, and Europe. It
4212-510: The greater susceptibility of the American elm, Ulmus americana , which masked the emergence of the second, far more virulent strain of the disease Ophiostoma novo-ulmi . It appeared in the United States sometime in the 1940s, and was originally believed to be a mutation of O. ulmi . Limited gene flow from O. ulmi to O. novo-ulmi was probably responsible for the creation of the North American subspecies O. novo-ulmi subsp. americana . It
4290-510: The hostilities on Germany , the origin of at least 40 cultivars, coincided with an outbreak of the early strain of DED, Ophiostoma ulmi . 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 DED Ophiostoma novo-ulmi in the late 1960s, brought
4368-424: The house of the title and is said to have a "...girth that a dozen men could not have spanned..." Forster describes the tree as "...a comrade, bending over the house, strength and adventure in its roots." The wych elm of the novel had pigs' teeth embedded in the trunk by country people long ago and it was said that chewing some of the bark could cure toothache. In keeping with the novel's epigraph, "Only connect...",
4446-715: The majority of the trees, although several are still lost each year. Younger American elms that have been planted in Central Park since the outbreak are of the DED-resistant 'Princeton' and 'Valley Forge' cultivars. Several rows of American elm trees that the National Park Service (NPS) first planted during the 1930s line much of the 1.9-mile-length (3 km) of the National Mall in Washington, DC. DED first appeared on
4524-451: The most 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 three to Europe, but the greatest diversity is in Asia with approximately two dozen species. The oldest fossils of Ulmus are leaves dating Paleocene , found across the Northern Hemisphere. The classification adopted in
4602-408: 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 quick growth and variety of foliage and forms, their tolerance of air-pollution, and the comparatively rapid decomposition of their leaf litter in the fall were further advantages. In North America,
4680-641: The oldest stands of American elms in the world. Along the Mall and Literary Walk four lines of American elms stretch over the walkway forming a cathedral-like covering. A part of New York City's urban ecology , the elms improve air and water quality, reduce erosion and flooding, and decrease air temperatures during warm days. While the stand is still vulnerable to DED, in the 1980s the Central Park Conservancy undertook aggressive countermeasures such as heavy pruning and removal of extensively diseased trees. These efforts have largely been successful in saving
4758-547: The pandemic, and a number may survive, or have regenerated, unrecognised. 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. Efforts to develop DED-resistant cultivars began in
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#17328383685134836-475: The plant's survival via stump sprouts. 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
4914-434: The plantsman's needs. Native species may be propagated by seed. In their natural setting, native species, 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. After pollination, seeds of spring-flowering elms ripen and fall at the start of summer (June); they remain viable for only
4992-402: 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 beetles , which act as vectors . The disease affects all species of elms native to North America and Europe, but many Asiatic species have evolved antifungal genes and are resistant. Fungal spores, introduced into wounds in the tree caused by
5070-435: The roots, and any seedlings are often consumed by uncontrolled deer populations, regeneration is very restricted, limited to sprouts from the stumps of young trees. The resultant decline has been extreme, and the wych elm is now uncommon over much of its former range. It is best propagated from seed or by layering stooled stock plants, although softwood cuttings taken in early June will root fairly reliably under mist. Wych elm
5148-587: The slippery elm ( Ulmus rubra ) has long been used as a demulcent , and is still produced commercially for this purpose in the US with approval for sale as a nutritional supplement by the 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
5226-620: The southern tip of Greenland ( 61°N ). The tree was by far the most common elm in the north and west of the British Isles and is now acknowledged as the only indisputably British native elm species. Owing to its former abundance in Scotland, the tree is occasionally known as the Scotch or Scots elm; Loch Lomond is said to be a corruption of the Gaelic Lac Leaman interpreted by some as 'Lake of
5304-402: The species most commonly planted was the American elm ( U. 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 field elm ( U. minor ) were the most widely planted in
5382-452: The tree to its nadir. Since around 1990, the elm has enjoyed a renaissance through the successful development in North America and Europe of cultivars highly resistant to DED. 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. Some of the latter, however, were by today's standards inadequately described or illustrated before
5460-565: The tree was found to have a slight to moderate susceptibility to elm yellows , and a high susceptibility to the elm leaf beetle Xanthogaleruca luteola . The wych elm is moderately shade-tolerant, but requires deep, rich soils as typically found along river valleys. The species is intolerant of acid soils and flooding, as it is of prolonged drought. Although rarely used as a street tree owing to its shape, it can be surprisingly tolerant of urban air pollution, constricted growing conditions, and severe pollarding. As wych elm does not sucker from
5538-406: The trees during the 1950s and reached a peak in the 1970s. The NPS used a number of methods to control the epidemic , including sanitation , pruning , injecting trees with fungicide , and replanting with DED-resistant cultivars. The NPS combated the disease's local insect vector , the smaller European elm bark beetle ( Scolytus multistriatus ), by trapping and by spraying with insecticides . As
5616-604: The upper slopes of Mount Šimonka in Slovakia , but they are believed to have survived courtesy of their isolation from disease-carrying beetles rather than any innate resistance; 50 clones of these trees were presented to the Prince of Wales for planting at his Highgrove Estate , and at Clapham , Yorkshire . E. M. Forster cites a particular wych elm, one that grew at his childhood home of Rooks Nest, Stevenage , Hertfordshire , 16 times in his novel Howards End . This tree overhangs
5694-413: The wych elm may be seen by some as a symbol of the connection of humans to the earth. Margaret Schlegel, the novel's protagonist, fears that any "....westerly gale might blow the wych elm down and bring the end of all things..." The tree is changed to a chestnut in the 1991 film adaptation of Howards End . About 40 cultivars have been raised, although at least 30 are now probably lost to cultivation as
5772-457: Was a true panacea." It was this so-called "pyramidal elm bark" about which Michel-Philippe Bouvart famously quipped "Take it, Madame... and hurry up while it [still] cures." It still appeared in a pharmacopeia of 1893. Possibly the oldest wych elm in Europe grew at Beauly Priory in Inverness-shire , Scotland; the tree succumbed to DED in 2022 and collapsed the following year. The priory
5850-521: Was first recognized in Britain in the early 1970s, believed to have been introduced via a cargo of Canadian rock elm destined for the boatbuilding industry, and rapidly eradicated most of the mature elms from western Europe. A second subspecies, O. novo-ulmi subsp. novo-ulmi , caused similar devastation in Eastern Europe and Central This subspecies, which was introduced to North America, and like O. ulmi ,
5928-731: Was founded circa 1230, the tree already in existence. The UK Champion listed in the Tree Register of the British Isles was at Brahan in the Scottish Highlands (died 2021 ); it had a girth of 703 cm (2.23 m DBH) and a height of 24 m. Possibly the oldest specimen in England was found in 2018 in a field north of Hopton Castle in Shropshire. Coppiced long ago, its bole girth measured 6.3 m in 2018. The oldest specimen in Edinburgh
6006-589: 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/m . Elm wood
6084-605: Was widely planted in Edinburgh in the 19th century as a park and avenue tree, and despite losses, it remains abundant there, regenerating through seedlings. It was introduced to New England in the 18th century, to Canada (as U. montana at the Dominion Arboretum , Ottawa ) and Australia in the 19th century. Wych elm wood is prized by craftsmen for its colouring, its striking grain, its 'partridge-breast' or 'catspaw' markings, and when worked, its occasional iridescent greenish sheen or 'bloom'. The bosses on old trees produce
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