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Alnus
Alders are trees of the genus ''Alnus'' in the birch family Betulaceae. The genus includes about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few species extending into Central America, as well as the northern and southern Andes. Description With a few exceptions, alders are deciduous, and the leaves are alternate, simple, and serrated. The flowers are catkins with elongate male catkins on the same plant as shorter female catkins, often before leaves appear; they are mainly wind-pollinated, but also visited by bees to a small extent. These trees differ from the birches (''Betula'', another genus in the family) in that the female catkins are woody and do not disintegrate at maturity, opening to release the seeds in a similar manner to many conifer cones. The largest species are red alder (''A. rubra'') on the west coast of North America, and black alder (''A. glutinosa''), native to mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alnus Acuminata
Alders are trees of the genus ''Alnus'' in the birch family Betulaceae. The genus includes about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few species extending into Central America, as well as the northern and southern Andes. Description With a few exceptions, alders are deciduous, and the leaves are alternate, simple, and serrated. The flowers are catkins with elongate male catkins on the same plant as shorter female catkins, often before leaves appear; they are mainly wind-pollinated, but also visited by bees to a small extent. These trees differ from the birches (''Betula'', another genus in the family) in that the female catkins are woody and do not disintegrate at maturity, opening to release the seeds in a similar manner to many conifer cones. The largest species are red alder (''A. rubra'') on the west coast of North America, and black alder (''A. glutinosa''), native ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alnus Serrulata Leaves
Alders are trees of the genus ''Alnus'' in the birch family Betulaceae. The genus includes about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few species extending into Central America, as well as the northern and southern Andes. Description With a few exceptions, alders are deciduous, and the leaves are alternate, simple, and serrated. The flowers are catkins with elongate male catkins on the same plant as shorter female catkins, often before leaves appear; they are mainly wind-pollinated, but also visited by bees to a small extent. These trees differ from the birches (''Betula'', another genus in the family) in that the female catkins are woody and do not disintegrate at maturity, opening to release the seeds in a similar manner to many conifer cones. The largest species are red alder (''A. rubra'') on the west coast of North America, and black alder (''A. glutinosa''), native to mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alnus Glutinosa
''Alnus glutinosa'', the common alder, black alder, European alder, European black alder, or just alder, is a species of tree in the family (biology), family Betulaceae, native plant, native to most of Europe, southwest Asia and northern Africa. It thrives in wet locations where its association with the bacterium ''Frankia alni'' enables it to grow in poor quality soils. It is a medium-sized, short-lived tree growing to a height of up to 30 metres (98 feet). It has short-stalked rounded leaves and separate male and female flowers in the form of catkins. The small, rounded fruits are cone-like and the seeds are dispersed by wind and water. The common alder provides food and shelter for wildlife, with a number of insects, lichens and fungi being completely dependent on the tree. It is a pioneer species, colonising vacant land and forming mixed forests as other trees appear in its wake. Eventually common alder dies out of woodlands because the seedlings need more light than is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alnus Alnobetula
''Alnus alnobetula'' is a common tree widespread across much of Europe, Asia, and North America. Many sources refer to it as ''Alnus viridis'', the green alder, but botanically this is considered an illegitimate name synonymous with ''Alnus alnobetula'' subsp. ''fruticosa''. Description It is a large shrub or small tree tall with smooth grey bark even in old age. The leaves are shiny green with light green undersurfaces, ovoid, long and 2–6 cm broad. The flowers are catkins, appearing late in spring after the leaves emerge (unlike other alders which flower before leafing out); the male catkins are pendulous, 4–8 cm long, the female catkins 1 cm long and 0.7 cm broad when mature in late autumn, in clusters of 3–10 on a branched stem. The seeds are small, long, light brown with a narrow encircling wing. The roots of ''Alnus viridis subsp. sinuata'' have nitrogen-fixing nodules. A study in Alaska showed that Sitka alder seedlings were able to invade co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alnus Cordata
''Alnus cordata'', the Italian alder, is a tree or shrub species belonging to the family Betulaceae, and native to the southern Apennine Mountains (Campania, Basilicata and Calabria, mainly on western mountain sides) and the north-eastern mountains of Corsica. It has been introduced in Sicily Sicily (Italian language, Italian and ), officially the Sicilian Region (), is an island in the central Mediterranean Sea, south of the Italian Peninsula in continental Europe and is one of the 20 regions of Italy, regions of Italy. With 4. ..., Sardinia, and more recently in Central Italy, Central-Northern Italy, other European countries (France, Belgium, Spain, Portugal, United Kingdom) and extra-European countries (Chile, New Zealand), where it has become naturalised. Description It is a medium-sized tree growing up to tall (exceptionally to ), with a trunk up to in diameter. The leaves are deciduous but with a very long season in leaf, from April to December in the Northern He ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Alder
''Alnus rubra'', the red alder, is a deciduous broadleaf tree native to western North America (Alaska, Yukon, British Columbia, Washington, Oregon, California, Idaho and Montana). Description ''Alnus rubra'' is the largest species of alder in North America and one of the largest in the world, reaching heights of . The official tallest red alder (as of 1979) stands tall in Clatsop County, Oregon (US). The trunks range from in diameter. The bark is mottled, ashy-gray and smooth, often colonized by white lichen and moss. The leaves are ovate, long, with bluntly serrated edges and a distinct point at the end; the leaf margin is revolute, the very edge being curled under, a diagnostic character which distinguishes it from all other alders. Rather than turning yellow in autumn, its leaves darken in colour and wither before they are shed. The male flowers are dangling reddish catkins long in early spring. Female flowers occur in clusters of (3) 4–6 (8). Female catkins are erect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alnus Serrulata
''Alnus serrulata'', the hazel alder or smooth alder, is a thicket-forming shrub in the family Betulaceae. It is native to eastern North America and can be found from western Nova Scotia and southern New Brunswick south to Florida and Texas. Description ''Alnus serrulata'' is a large shrub or small tree that may grow up to high and in diameter. The scientific name originates from alnus which is an old name for alder; serrulata points to the finely-toothed leaf margins which it possesses. It takes about 10 yrs to mature. The plant prefers moist soil near streams, pond margins, and riversides. It usually has multiple stems from its base and reddish-green flowers. The broad, flat, dark green leaves are about 2 to 4 inches long. Leaf: The simple, round leaves are obovate, 2 to 5 in long, 1.2 to 2.8 in wide, obtuse, wider at middle, and V-shaped base. Veins are pinnate and conspicuous. Leaves have a smooth texture above and hairy texture below. The upper side of the leaves are dar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betulaceae
Betulaceae, the birch family, includes six genera of deciduous nut-bearing trees and shrubs, including the birches, alders, hazels, hornbeams, hazel-hornbeam, and hop-hornbeams, numbering a total of 167 species. They are mostly natives of the temperate Northern Hemisphere, with a few species reaching the Southern Hemisphere in the Andes in South America. Their typical flowers are catkins and often appear before leaves. In the past, the family was often divided into two families, Betulaceae (''Alnus'', ''Betula'') and Corylaceae (the rest). Recent treatments, including the Angiosperm Phylogeny Group, have described these two groups as subfamilies within an expanded Betulaceae: Betuloideae and Coryloideae. Betulaceae flowers are monoecious, meaning that they have both male and female flowers on the same tree. Their flowers present as catkins and are small and inconspicuous, often with reduced perianth parts. These flowers have large feathery stamen and produce a high vo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, e.g., including only woody plants with secondary growth, only plants that are usable as lumber, or only plants above a specified height. But wider definitions include taller palms, tree ferns, bananas, and bamboos. Trees are not a monophyletic taxonomic group but consist of a wide variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight. The majority of tree species are angiosperms or hardwoods; of the rest, many are gymnosperms or softwoods. Trees tend to be long-lived, some trees reaching several thousand years old. Trees evolved around 400 million years ago, and it is estimated that there are around three trillion mature trees in the world currently. A tree typically has many secondary branches supported cle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conifer Cone
A conifer cone, or in formal botanical usage a strobilus, : strobili, is a seed-bearing organ on gymnosperm plants, especially in conifers and cycads. They are usually woody and variously conic, cylindrical, ovoid, to globular, and have scales and bracts arranged around a central axis, but can be fleshy and berry-like. The cone of Pinophyta (conifer clade) contains the reproductive structures. The woody cone is the female cone, which produces seeds. The male cone, which produces pollen, is usually ephemeral and much less conspicuous even at full maturity. The name "cone" derives from Greek ''konos'' (pine cone), which also gave name to the geometric cone. The individual plates of a cone are known as ''scales''. In conifers where the cone develops over more than one year (such as pines), the first year's growth of a seed scale on the cone, showing up as a protuberance at the end of the two-year-old scale, is called an ''umbo'', while the second year's growth is called th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
