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Ulmus 'Delaware'
The American Elm cultivar ''Ulmus americana'' 'Delaware' was originally selected (as tree number 218, a c.1940 seedling from North Dakota) from 35,000 seedlings inoculated with the Dutch elm disease fungus in USDA trials at Morristown, New Jersey. Description The tree has a relatively low stature and "undesirable" branching habit.Townsend, A. M., Bentz, S. E., and Douglass L. W. (2005)Evaluation of 19 American Elm Clones for Tolerance to Dutch Elm Disease ''Journal of Environmental Horticulture'', March 2005, Horticultural Research Institute, Washington, D.C. Pests and diseases Further disease-resistance trials were conducted by both the USDA and the United States National Arboretum which confirmed the clone had a fair level of resistance to Dutch elm disease. 'Delaware' is susceptible to Elm Yellows, but resistant to the Elm Leaf Beetle '' Xanthogaleruca luteola''. Cultivation The original tree, which had been moved to the USDA National Arboretum, Washington, D. C. in 194 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ulmus Americana
''Ulmus americana'', generally known as the American elm or, less commonly, as the white elm or water elm, is a species of elm native to eastern North America, naturally occurring from Nova Scotia west to Alberta and Montana, and south to Florida and central Texas. The American elm is an extremely hardy tree that can withstand winter temperatures as low as −42 ° C (−44 ° F). Trees in areas unaffected by Dutch elm disease (DED) can live for several hundred years. A prime example of the species was the Sauble Elm, which grew beside the banks of the Sauble River in Ontario, Canada, to a height of 43 m (140 ft), with a d.b.h of 196 cm (6.43 ft) before succumbing to DED; when it was felled in 1968, a tree-ring count established that it had germinated in 1701. For over 80 years, ''U. americana'' had been identified as a tetraploid, i.e. having double the usual number of chromosomes, making it unique within the genus. However, a study published in 2011 b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Elm
''Ulmus americana'', generally known as the American elm or, less commonly, as the white elm or water elm, is a species of elm native to eastern North America, naturally occurring from Nova Scotia west to Alberta and Montana, and south to Florida and central Texas. The American elm is an extremely hardy tree that can withstand winter temperatures as low as −42 ° C (−44 ° F). Trees in areas unaffected by Dutch elm disease (DED) can live for several hundred years. A prime example of the species was the Sauble Elm, which grew beside the banks of the Sauble River in Ontario, Canada, to a height of 43 m (140 ft), with a d.b.h of 196 cm (6.43 ft) before succumbing to DED; when it was felled in 1968, a tree-ring count established that it had germinated in 1701. For over 80 years, ''U. americana'' had been identified as a tetraploid, i.e. having double the usual number of chromosomes, making it unique within the genus. However, a study published in 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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, or carefully controlled seed production. Most cultivars arise from purposeful human manipulation, but some originate from wild plants that have distinctive characteristics. Cultivar names are chosen according to rules of the International Code of Nomenclature for Cultivated Plants (ICNCP), and not all cultivated plants qualify as cultivars. Horticulturists generally believe the word ''cultivar''''Cultivar'' () has two meanings, as explained in '' Formal definition'': it is a classification category and a taxonomic unit within the category. When referring to a taxon, the word does not apply to an individual plant but to all plants that share the unique characteristics that define the cultivar. was coined as a term meaning "cultivated vari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 America, Europe, and New Zealand. In these regions it has devastated native populations of elms that did not have resistance to the disease. The name "Dutch elm disease" refers to its identification in 1921 and later in the Netherlands by Dutch phytopathologists Bea Schwarz and Christine Buisman, who both worked with professor Johanna Westerdijk. The disease affects species in the genera ''Ulmus'' and ''Zelkova''; therefore it is not specific to the Dutch elm hybrid. Overview Dutch elm disease (DED) is caused by ascomycete microfungi.Ascomycetes: Phylum Ascomycota< ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USDA
The United States Department of Agriculture (USDA) is the federal executive department responsible for developing and executing federal laws related to farming, forestry, rural economic development, and food. It aims to meet the needs of commercial farming and livestock food production, promotes agricultural trade and production, works to assure food safety, protects natural resources, fosters rural communities and works to end hunger in the United States and internationally. It is headed by the Secretary of Agriculture, who reports directly to the President of the United States and is a member of the president's Cabinet. The current secretary is Tom Vilsack, who has served since February 24, 2021. Approximately 80% of the USDA's $141 billion budget goes to the Food and Nutrition Service (FNS) program. The largest component of the FNS budget is the Supplemental Nutrition Assistance Program (formerly known as the Food Stamp program), which is the cornerstone of USDA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morristown, New Jersey
Morristown () is a town and the county seat of Morris County, in the U.S. state of New Jersey.New Jersey County Map . Accessed July 10, 2017. Morristown has been called "the military capital of the American Revolution" because of its strategic role in the war for independence from Great Britain. Today this history is visible in a variety of locations throughout the town that collectively make up [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Jersey
New Jersey is a U.S. state, state in the Mid-Atlantic States, Mid-Atlantic and Northeastern United States, Northeastern regions of the United States. It is bordered on the north and east by the state of New York (state), New York; on the east, southeast, and south by the Atlantic Ocean; on the west by the Delaware River and Pennsylvania; and on the southwest by Delaware Bay and the state of Delaware. At , New Jersey is the List of U.S. states and territories by area, fifth-smallest state in land area; but with close to 9.3 million residents, it ranks List of U.S. states and territories by population, 11th in population and List of U.S. states and territories by population density, first in population density. The state capital is Trenton, New Jersey, Trenton, and the most populous city is Newark, New Jersey, Newark. With the exception of Warren County, New Jersey, Warren County, all of the state's 21 counties lie within the combined statistical areas of New York City or Delaw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photo Of The Bark Of The American Elm Cultivar 'Delaware'
A photograph (also known as a photo, image, or picture) is an image created by light falling on a photosensitive surface, usually photographic film or an electronic image sensor, such as a CCD or a CMOS chip. Most photographs are now created using a smartphone/ camera, which uses a lens to focus the scene's visible wavelengths of light into a reproduction of what the human eye would see. The process and practice of creating such images is called photography. Etymology The word ''photograph'' was coined in 1839 by Sir John Herschel and is based on the Greek φῶς (''phos''), meaning "light," and γραφή (''graphê''), meaning "drawing, writing," together meaning "drawing with light." History The first permanent photograph, a contact-exposed copy of an engraving, was made in 1822 using the bitumen-based " heliography" process developed by Nicéphore Niépce. The first photographs of a real-world scene, made using a camera obscura, followed a few years later at L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States National Arboretum
The United States National Arboretum is an arboretum in northeast Washington, D.C., operated by the United States Department of Agriculture's Agricultural Research Service. It was established in 1927 by an act of Congress after a campaign by USDA Chief Botanist Frederick Vernon Coville. It is in size and is located northeast of the United States Capitol, Capitol building, with entrances on New York Avenue (Washington, D.C.), New York Avenue, NE and R Street, NE. The campus's gardens, collections, and features are connected by roadways that are long in total. In addition to the main campus in Washington, D.C., there are research locations at the Henry A. Wallace Beltsville Agricultural Research Center in Beltsville, Maryland and in McMinnville, Tennessee, McMinville, Tennessee. The Arboretum functions as a major center of botany, botanical research conducted by the USDA, including applied research on trees, shrubs, turf, and the development of new ornamental plants. In addition t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elm Yellows
Elm yellows is a plant disease of elm trees that is spread by leafhoppers or by root grafts."Elm Yellows." Elmcare.Com. 19 Mar. 2008 . Elm yellows, also known as elm phloem necrosis, is very aggressive, with no known cure. Elm yellows 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.Price, Terry. "Wilt Diseases." Forestpests.Org. 23 Mar. 2005. 19 Mar. 2008 . Similar phytoplasmas, also known confusingly as 'Elm yellows', also occur in Europe.Conti, M., D'Agostino, G., Mittembergher, L. (1987) A recent epiphytotic of elm yellows in Italy. ''Proceedings of the 7th Congress of the Mediterranean Phytopathological Union'', 208–209. Consejeria de Agricultura y Pesca de la Junta de Andalucia, Granada, Spain 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. Importance E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanthogaleruca Luteola
''Xanthogaleruca luteola'', commonly known as the elm-leaf beetle, is a beetle species in the family Chrysomelidae that is native to Europe but invasive in other parts of the world.http://cisr.ucr.edu/elm_leaf_beetle.html - Center for Invasive Species Research Description The imago (adult beetle) is 6–8 mm in length, and ranges from yellow to green in colour, with a spot on its head, an hourglass mark and two spots on the pronotum, and a broad, dark stripe along the edge of each elytron. The larvae are usually black, occasionally black and yellow, with multiple rows of dots on the back and on the sides and < 13 mm long. The are orange-yellow with black e. The ova are yellow, and laid in spindle-like clusters of < 25 on the undersides of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Washington, D
Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered on Washington, D.C. * George Washington (1732–1799), the first president of the United States Washington may also refer to: Places England * Washington, Tyne and Wear, a town in the City of Sunderland metropolitan borough ** Washington Old Hall, ancestral home of the family of George Washington * Washington, West Sussex, a village and civil parish Greenland * Cape Washington, Greenland * Washington Land Philippines * New Washington, Aklan, a municipality *Washington, a barangay in Catarman, Northern Samar *Washington, a barangay in Escalante, Negros Occidental *Washington, a barangay in San Jacinto, Masbate *Washington, a barangay in Surigao City United States * Washington, Wisconsin (other) * Fort Washington (disambigu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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