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The Trees Portal

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, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height. In wider definitions, the taller palms, tree ferns, bananas, and bamboos are also trees.

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 370 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 clear of the ground by the trunk, which typically contains woody tissue for strength, and vascular tissue to carry materials from one part of the tree to another. For most trees the trunk is surrounded by a layer of bark which serves as a protective barrier. Below the ground, the roots branch and spread out widely; they serve to anchor the tree and extract moisture and nutrients from the soil. Above ground, the branches divide into smaller branches and shoots. The shoots typically bear leaves, which capture light energy and convert it into sugars by photosynthesis, providing the food for the tree's growth and development.

Trees usually reproduce using seeds. Flowering plants have their seeds inside fruits, while conifers carry their seeds in cones, and tree ferns produce spores instead.

Trees play a significant role in reducing erosion and moderating the climate. They remove carbon dioxide from the atmosphere and store large quantities of carbon in their tissues. Trees and forests provide a habitat for many species of animals and plants. Tropical rainforests are among the most biodiverse habitats in the world. Trees provide shade and shelter, timber for construction, fuel for cooking and heating, and fruit for food as well as having many other uses. In much of the world, forests are shrinking as trees are cleared to increase the amount of land available for agriculture. Because of their longevity and usefulness, trees have always been revered, with sacred groves in various cultures, and they play a role in many of the world's mythologies. (Full article...)

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Alloxylon flammeum, commonly known as the Queensland tree waratah or red silky oak, is a medium-sized tree of the family Proteaceae found in the Queensland tropical rain forests of northeastern Australia. It has shiny green elliptical leaves up to 18 cm (7.1 in) long, and prominent orange-red inflorescences that appear from August to October, followed by rectangular woody seed pods that ripen in February and March. Juvenile plants have large (up to 25 cm (9.8 in) long) deeply lobed pinnate leaves. Previously known as Oreocallis wickhamii, the initial specimen turned out to be a different species to the one cultivated and hence a new scientific name was required. Described formally by Peter Weston and Mike Crisp in 1991, A. flammeum was designated the type species of the genus Alloxylon. This genus contains the four species previously classified in Oreocallis that are found in Australasia.

Alloxylon flammeum is a canopy or emergent tree of the Mabi rainforest community of north Queensland. Its terminal tubular flowers indicate that the species is pollinated by birds. Readily adaptable to cultivation, Alloxylon flammeum prefers a site with good drainage and responds well to extra moisture and fertilisers low in phosphorus. It is listed nationally as vulnerable under the Australian Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) as most of its habitat has been cleared for agriculture and logging. (Full article...)

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... that the Easter egg tree (pictured) in Saalfeld, Thuringia, was decorated with 10,000 Easter eggs in 2012?
... that the Living Willow Theatre, an open air theatre constructed of living willow trees, is located near the village of Llanwrthwl and occasionally holds outdoor performances of Shakespeare?
... that Wollemi Stringybark, a tree that grows to 45 metres (148 ft) high northwest of Sydney, remains officially undescribed?
... that Linton Park in Kent, England, has an avenue of Giant Sequoia trees planted in 1864?
... that the Eduardo Avaroa Andean Fauna National Reserve contains a "stone tree"?
... that the scarlet honey myrtle, an ornamental garden shrub, is from the same genus as the punk tree?
... that the towers of architect Terunobu Fujimori's Lamune Onsen have pine trees planted on the apex of their roofs?

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European beech (Fagus sylvatica)

Beech (Fagus) is a genus of deciduous trees in the family Fagaceae, native to subtropical (accessory forest element) and temperate (as dominant element of mesophytic forests) Eurasia and North America. There are 14 accepted species in two distinct subgenera, Englerianae Denk & G.W.Grimm and Fagus. The subgenus Englerianae is found only in East Asia, distinctive for its low branches, often made up of several major trunks with yellowish bark. The better known species of subgenus Fagus are native to Europe, western and eastern Asia and eastern North America. They are high-branching trees with tall, stout trunks and smooth silver-grey bark.

The European beech Fagus sylvatica is the most commonly cultivated species, yielding a utility timber used for furniture construction, flooring and engineering purposes, in plywood, and household items. The timber can be used to build homes. Beechwood makes excellent firewood. Slats of washed beech wood are spread around the bottom of fermentation tanks for Budweiser beer. Beech logs are burned to dry the malt used in some German smoked beers. Beech is also used to smoke Westphalian ham, andouille sausage, and some cheeses. (Full article...)

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General images

The following are images from various tree-related articles on Wikipedia.

Image 1Dormant buds of ash, Fraxinus excelsior (from Tree)
Image 2Lepidodendron, an extinct lycophyte tree (from Tree)
Image 3An avenue of London planes (Platanus × hispanica) in a garden in Belgium. (from Tree)
Image 4Priest River winding through Whitetail Butte with lots of forestry to the east—these lot patterns have existed since the mid-19th century. The white patches reflect areas with younger, smaller trees, where winter snow cover shows up brightly to the astronauts. Dark green-brown squares are parcels (from Forest)
Image 5Share of forest area in total land area, top countries (2021) (from Forest)
Image 6Wind dispersed seed of elm (Ulmus), ash (Fraxinus) and maple (Acer) (from Tree)
Image 7Diagram of secondary growth in a eudicot or coniferous tree showing idealised vertical and horizontal sections. A new layer of wood is added in each growing season, thickening the stem, existing branches and roots. (from Tree)
Image 8Selling firewood at a market (from Tree)
Image 9Forest in the Scottish Highlands (from Forest)
Image 10Share of land that is covered by forest (from Forest)
Image 11European larch (Larix decidua), a coniferous tree which is also deciduous (from Tree)
Image 12Trees in art: Weeping Willow, Claude Monet, 1918 (from Tree)
Image 13Neem tree at Sant Nenuram Ashram (from Trees of Pakistan)
Image 14Redwood tree in northern California redwood forest, where many redwood trees are managed for preservation and longevity, rather than being harvested for wood production (from Forest)
Image 15Even, dense old-growth stand of beech trees (Fagus sylvatica) prepared to be regenerated by their saplings in the understory, in the Brussels part of the Sonian Forest. (from Forest)
Image 16People trees, by Pooktre (from Tree)
Image 17Fraxinus excelsior (from List of trees of Great Britain and Ireland)
Image 18Buttress roots of the kapok tree (Ceiba pentandra) (from Tree)
Image 19A section of yew (Taxus baccata) showing 27 annual growth rings, pale sapwood and dark heartwood (from Tree)
Image 20World production of selected forest products (from Forest)
Image 21The Daintree Rainforest (from Tree)
Image 22Yggdrasil, the World Ash of Norse mythology (from Tree)
Image 23Common ash (Fraxinus excelsior), a deciduous broad-leaved (angiosperm) tree (from Tree)
Image 24Alnus glutinosa (from List of trees of Great Britain and Ireland)
Image 25Buds, leaves and reproductive structures of white fir, Abies alba (from Tree)
Image 26Recently stripped cork oak (Quercus suber) (from Tree)
Image 27Casentinesi Forests, Italy (from Forest)
Image 28Roof trusses made from softwood (from Tree)
Image 29Cracked thorny skin of a Aesculus tree seed (from Tree)
Image 30Olive trees in Pakistan (from Trees of Pakistan)
Image 31Since the 13th century, the Niepołomice Forest in Poland has had special use and protection. In this view from space, different coloration can indicate different functions. (from Forest)
Image 32Latvian Pine Forest in Ķegums Municipality (from Forest)
Image 33Palms and cycads as they might have appeared in the middle Tertiary (from Tree)
Image 34Northern beech (Fagus sylvatica) trunk in autumn (from Tree)
Image 35Latex collecting from a rubber tree (Hevea brasiliensis) (from Tree)
Image 36Sugar maple (Acer saccharum) tapped to collect sap for maple syrup (from Tree)
Image 37A young red pine (Pinus resinosa) with spread of roots visible, as a result of soil erosion (from Tree)
Image 38Proportion of forest in protected areas, by region, 2020 (from Forest)
Image 39A forest near Vinitsa, North Macedonia (from Forest)
Image 40Temperate rainforest in Tasmania's Hellyer Gorge (from Forest)
Image 41Informal upright style of bonsai on a juniper tree (from Tree)
Image 42The Amazon rainforest alongside the Solimões River, a tropical rainforest. These forests are the most biodiverse and productive ecosystems in the world. (from Forest)
Image 43Conifers in the Swabian alps (from Tree)
Image 44Garibaldi Provincial Park, British Columbia (from Forest)
Image 45Yellow cassia, an ornamental tree with yellow flowers (from Tree)
Image 46Burned forest on Thasos (from Forest)
Image 47Broadleaf forest in Bhutan (from Forest)
Image 48Proportion and distribution of global forest area by climatic domain, 2020 (from Forest)
Image 49Form, leaves and reproductive structures of queen sago, Cycas circinalis (from Tree)
Image 50Tall herbaceous monocotyledonous plants such as banana lack secondary growth, but are trees under the broadest definition. (from Tree)
Image 51Malus sylvestris (from List of trees of Great Britain and Ireland)
Image 52The General Sherman Tree, thought to be the world's largest by volume (from Tree)
Image 534000 years old Cypress of Abarqu is the oldest tree in Iran and the second oldest tree in the world. (from List of trees of Iran)
Image 54Buds, leaves, flowers and fruit of pedunculate oak, Quercus robur (from Tree)
Image 55Rowan tree in Wicklow, Ireland (from List of trees of Great Britain and Ireland)
Image 56Spiny forest at Ifaty, Madagascar, featuring various Adansonia (baobab) species, Alluaudia procera (Madagascar ocotillo) and other vegetation (from Forest)