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Birch Dieback
Birch dieback is a disease of birch trees that causes the branches in the crown to die off. The disease may eventually kill the tree. In an event in the Eastern United States and Canada in the 1930s and 1940s, no causal agent was found, but the wood-boring beetle, the bronze birch borer, was implicated in the severe damage and death of the tree that often followed. In similar crown dieback occurrences in Europe several decades later, the pathogenic fungus '' Melanconium betulinum'' were found in association with affected trees, as well as '' Anisogramma virgultorum'' and ''Marssonina betulae''. Description Birch dieback tends to attack trees that are under stress, such as from drought, through winter kill or exposure to phenoxy herbicides used to control broad-leafed weeds in cereal crops. First, the foliage becomes scant and develops chlorosis or the leaves at the tips of the shoots start to curl. Then the twigs become bare as new leaves fail to develop. Whole branches may die as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birch
A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech-oak family Fagaceae. The genus ''Betula'' contains 30 to 60 known taxa of which 11 are on the IUCN 2011 Red List of Threatened Species. They are a typically rather short-lived pioneer species widespread in the Northern Hemisphere, particularly in northern areas of temperate climates and in boreal climates. Description Birch species are generally small to medium-sized trees or shrubs, mostly of northern temperate and boreal climates. The simple leaves are alternate, singly or doubly serrate, feather-veined, petiolate and stipulate. They often appear in pairs, but these pairs are really borne on spur-like, two-leaved, lateral branchlets. The fruit is a small samara, although the wings may be obscure in some species. They differ from the alders (''Alnus'', another genus in the family) in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betula Alleghaniensis
''Betula alleghaniensis'', the yellow birch, golden birch, or swamp birch, is a large tree and an important lumber species of birch native to northeastern North America. Its vernacular names refer to the golden color of the tree's bark. In the past the species name was ''Betula lutea''. ''Betula alleghaniensis'' is the provincial tree of Quebec, where it is commonly called ''merisier'', a name which in France is used for the wild cherry. Description It is a medium-sized, typically single stemmed, deciduous tree reaching tall (exceptionally to ) with a trunk typically in diameter, making it the largest North American species of birch. Yellow birch is long-lived, typically 150 years and some old growth forest specimens may last for 300 years. It mostly reproduces by seed. Mature trees typically start producing seeds at about 40 years but may start as young as 20. The optimum age for seed production is about 70 years. Good seed crops are not produced every year, and tend to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centre For Ecology And Hydrology
The UK Centre for Ecology & Hydrology (UKCEH) is a centre for excellence in environmental science across water, land and air. The organisation has a long history of investigating, monitoring and modelling environmental change, and its science makes a difference in the world. The issues that its science addresses include: air pollution, biodiversity, chemical risks in the environment, extreme weather events, droughts, floods, greenhouse gas emissions, soil health, sustainable agriculture, sustainable ecosystems, water quality, and water resources management. UKCEH coordinates a number of long-term environmental science monitoring sites and programmes, including the Predatory Bird Monitoring Scheme, the Isle of May Long-Term Study, the UK National River Flow Archive, the Plynlimon catchment study, lakes monitoring at Loch Leven and in the English Lake District, the UK Cosmic-ray soil moisture monitoring network (COSMOS-UK), the UK Upland Waters Monitoring Network and the UKCEH Coun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betula Pubescens
''Betula pubescens'' (syn. ''Betula alba''), commonly known as downy birch and also as moor birch, white birch, European white birch or hairy birch, is a species of deciduous tree, native and abundant throughout northern Europe and northern Asia, growing farther north than any other broadleaf tree. It is closely related to, and often confused with, the silver birch (''B. pendula''), but grows in wetter places with heavier soils and poorer drainage; smaller trees can also be confused with the dwarf birch (''B. nana''). Six varieties are recognised and it hybridises with the silver and dwarf birches. A number of cultivars have been developed but many are no longer in cultivation. The larva of the autumnal moth (''Epirrita autumnata'') feeds on the foliage and in some years, large areas of birch forest can be defoliated by this insect. Many fungi are associated with the tree and certain pathogenic fungi are the causal agents of birch dieback disease. The tree is a pioneer species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betula Pendula
''Betula pendula'', commonly known as silver birch, warty birch, European white birch, or East Asian white birch, is a species of tree in the family Betulaceae, native to Europe and parts of Asia, though in southern Europe, it is only found at higher altitudes. Its range extends into Siberia, China, and southwest Asia in the mountains of northern Turkey, the Caucasus, and northern Iran. It has been introduced into North America, where it is known as the European white birch or weeping birch and is considered invasive in some states in the United States and parts of Canada. The tree can also be found in more temperate regions of Australia. The silver birch is a medium-sized deciduous tree that owes its common name to the white peeling bark on the trunk. The twigs are slender and often pendulous and the leaves are roughly triangular with doubly serrate margins and turn yellow and brown in autumn before they fall. The flowers are catkins and the light, winged seeds get widely sc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Armillaria
''Armillaria'' is a genus of fungi that includes the '' A. mellea'' species known as honey fungi that live on trees and woody shrubs. It includes about 10 species formerly categorized summarily as ''A. mellea''. ''Armillarias'' are long-lived and form the largest living fungi in the world. The largest known organism (of the species ''Armillaria ostoyae'') covers more than in Oregon's Malheur National Forest and is estimated to be 2,500 years old. Some species of ''Armillaria'' display bioluminescence, resulting in foxfire. ''Armillaria'' can be a destructive forest pathogen. It causes "white rot" root disease (see Plant pathology section) of forests, which distinguishes it from ''Tricholoma'', a mycorrhizal (non-parasitic) genus. Because ''Armillaria'' is a facultative saprophyte, it also feeds on dead plant material, allowing it to kill its host, unlike parasites that must moderate their growth to avoid host death. Description The basidiocarp (reproductive struc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betula Populifolia
''Betula populifolia'' (gray or grey birch) is a deciduous tree native to eastern North America. Range It ranges from southeastern Ontario east to Nova Scotia, and south to Pennsylvania and New Jersey, with disjunct populations in Indiana, Virginia, and North Carolina. It prefers poor, dry upland soils, but is also found in moist mixed woodlands. Living only about 30 years, it is a common pioneer species on abandoned fields and burned areas. It is possibly extirpated in Delaware. Characteristics Gray birch grows quickly to 20 to 30 feet (6.9 to 9.1 m) tall and 15 inch (38 cm) trunk diameter, with an irregular open crown of slender branches. The tree often has multiple trunks branching off an old stump. The leaves are 2 to 2.7 inches (5-7 cm) long by 1.6 to 2.4 inches (4-6 cm) wide, alternately arranged, ovate, and tapering to an elongated tip. They are dark green and glabrous above and paler below, with a coarsely serrated margin. The bark is chalky to grayish white wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betula Papyrifera
''Betula papyrifera'' (paper birch, also known as (American) white birch and canoe birch) is a short-lived species of birch native to northern North America. Paper birch is named for the tree's thin white bark, which often peels in paper like layers from the trunk. Paper birch is often one of the first species to colonize a burned area within the northern latitudes, and is an important species for moose browsing. The wood is often used for pulpwood and firewood. Description It is a medium-sized deciduous tree typically reaching tall, and exceptionally to with a trunk up to in diameter. Within forests, it often grows with a single trunk but when grown as a landscape tree it may develop multiple trunks or branch close to the ground. Paper birch is a typically short-lived species. It handles heat and humidity poorly and may live only 30 years in zones six and up, while trees in colder-climate regions can grow for more than 100 years. ''B. papyrifera'' will grow in many so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bouleau
Gilles Bouleau (born 25 May 1962) is a French journalist. As a journalist and reporter on TF1 and LCI for several years, he spent several years in other countries as a correspondent in London and Washington. Head of special operations since 2011, he became the news anchor of the ''Journal de 20 heures'' on TF1 since June 2012, succeeding Laurence Ferrari. Early life and education Gilles Bouleau was born in Paris but spend his childhood in Colombes in the department of Hauts-de-Seine. He studied and graduated at the Centre de Formation des Journalistes (CFJ) of Paris and at the Institut d'Études Politiques of Paris ( Sciences Po). Television career In 1986, Gilles Bouleau joined the redaction service of TF1. He passed by the economic and social services, domestic policy, reportages and general information. He then presented all kind of reportages like Yugoslavia in 1987, the French presidential election of 1988, the 1992 and 1994 Winter Olympics. From 1996 to 1999, he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crown (botany)
The crown of a plant refers to the total of an individual plant's aboveground parts, including stems, leaves, and reproductive structures. A plant community canopy consists of one or more plant crowns growing in a given area. The crown of a woody plant (tree, shrub, liana) is the branches, leaves, and reproductive structures extending from the trunk or main stems. Shapes of crowns are highly variable. The major types for trees are the excurrent branching habit resulting in conoid shapes and decurrent (deliquescent) branching habit, resulting in round shapes. Crowns are also characterized by their width, depth, surface area, volume, and density. Measurements of crowns are important in quantifying and qualifying plant health, growth stage, and efficiency. Major functions of the crown include light energy assimilation, carbon dioxide absorption and release of oxygen via photosynthesis, energy release by respiration, and movement of water to the atmosphere by transpiration. Thes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorosis
In botany, chlorosis is a condition in which leaves produce insufficient chlorophyll. As chlorophyll is responsible for the green color of leaves, chlorotic leaves are pale, yellow, or yellow-white. The affected plant has little or no ability to manufacture carbohydrates through photosynthesis and may die unless the cause of its chlorophyll insufficiency is treated and this may lead to a plant diseases called rusts, although some chlorotic plants, such as the albino ''Arabidopsis thaliana'' mutant ''ppi2'', are viable if supplied with exogenous sucrose. The word ''chlorosis'' is derived from the Greek ''khloros'' meaning "greenish-yellow", "pale green", "pale", "pallid", or "fresh". In viticulture, the most common symptom of poor nutrition in grapevines is the yellowing of grape leaves caused by chlorosis and the subsequent loss of chlorophyll. This is often seen in vineyard soils that are high in limestone such as the Italian wine region of Barolo in the Piedmont, the Spanish wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
