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Golden elm tree with Dutch elm disease. 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.
The American elm is a deciduous tree which, under ideal conditions, can grow to heights of 21 to 35 meters (69 to 115 feet). [3] The trunk may have a diameter at breast height (dbh) of more than 1.2 m (4 ft), supporting a high, spreading umbrella-like canopy.
However, the tree was judged to have little ornamental value in the National Elm Trial . [3] The clone grows moderately quickly, averaging an increase of > 1 m in height per annum when young, reaching a height of <17 m in 25 to 30 years. [6] The leaves are < 13 cm in length by 9 cm broad, coarsely-toothed, and with a 4 mm petiole.
The tree produces spiky green fruits about the size of a golf ball, which turn brown and drop off the tree over an extended period beginning in fall and continuing over the winter.
Ulmus davidiana var. japonica 'JFS-Bieberich' (sold as Emerald Sunshine) is a Japanese Elm cultivar that was raised by the Sunshine Nursery, Oklahoma, from seed collected in China by proprietor Steve Bieberich. [1] Emerald Sunshine proved only moderately successful in the US National Elm Trial, averaging a survival rate of 70% overall. [2]
Ulmus laevis Pall., variously known as the European white elm, [2] fluttering elm, spreading elm, stately elm and, in the United States, the Russian elm, is a large deciduous tree native to Europe, from France [3] northeast to southern Finland, east beyond the Urals into Kyrgyzstan and Kazakhstan, and southeast to Bulgaria and the Crimea; there are also disjunct populations in the Caucasus and ...
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. [61] The "Great Elm Tree" at Phillips Academy in Andover, Massachusetts is believed to have been standing for at least 200 years. It is being well cared for and receives regular treatments for Dutch elm disease.
Ulmus castaneifolia Hemsley, [3] the chestnut-leafed elm or multinerved elm, is a small deciduous tree found across much of China in broadleaved forests at elevations of 500–1,600 metres (1,600–5,200 ft).