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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 reaching several thousand years old. Trees have been in existence for 370 million years. It is estimated that there are around three trillion mature trees in the world.

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 it 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. Flowers and fruit may be present, but some trees, such as conifers, instead have pollen cones and seed cones. Palms, bananas, and bamboos also produce seeds, but 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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The Mingo Oak (also known as the Mingo White Oak) was a white oak (Quercus alba) in the U.S. state of West Virginia. First recognized for its age and size in 1931, the Mingo Oak was the oldest and largest living white oak tree in the world until its death in 1938.

The Mingo Oak stood in Mingo County, West Virginia, in a cove at the base of Trace Mountain near the headwaters of the Trace Fork of Pigeon Creek, a tributary stream of Tug Fork. The tree reached a height of over 200 feet (61 m), and its trunk was 145 feet (44 m) in height. Its crown measured 130 feet (40 m) in diameter and 60 feet (18 m) in height. The tree's trunk measured 9 feet 10 inches (3.00 m) in diameter and the circumference of its base measured 30 feet 9 inches (9.37 m). Assessments of its potential board lumber ranged from 15,000 feet (4,600 m) to 40,000 feet (12,000 m). Following the tree's felling in 1938, it was estimated to weigh approximately 5,400 long tons (5,500 t). (Full article...)

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... that veneration of the Amla tree (pictured), in particular on Amalaka Ekadashi, is due to the belief that the god Vishnu resides in and near the tree?
... that the future of the tropical tree Milicia regia for timber production is threatened by a gall fly, Phytolyma lata?
... that the churchyard of All Saints Church, Ulcombe in England contains a yew tree claimed to be more than 2,000 years old?
... that seeds of the extinct tree Eucommia eocenica have been found with latex covered fossils?
... that the fruits of the Lecythis ampla tree resemble little wooden pots with lids?
... that fossilized seeds of the extinct tree Eucommia montana are found from British Columbia to Colorado?
... that the Australian tree Agathis atropurpurea is known as the black kauri or the blue kauri because of the colour of its bark?

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The almond (Prunus amygdalus, syn. Prunus dulcis) is a species of small tree from the genus Prunus, cultivated worldwide for its seed, a culinary nut. Along with the peach, it is classified in the subgenus Amygdalus, distinguished from the other subgenera by corrugations on the shell (endocarp) surrounding the seed.

The fruit of the almond is a drupe, consisting of an outer hull and a hard shell with the seed, which is not a true nut. Shelling almonds refers to removing the shell to reveal the seed. Almonds are sold shelled or unshelled. Blanched almonds are shelled almonds that have been treated with hot water to soften the seedcoat, which is then removed to reveal the white embryo. Once almonds are cleaned and processed, they can be stored over time. Almonds are used in many cuisines, often featuring prominently in desserts, such as marzipan. (Full article...)

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General images

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

Image 1Common ash (Fraxinus excelsior), a deciduous broad-leaved (angiosperm) tree (from Tree)
Image 2Garibaldi Provincial Park, British Columbia (from Forest)
Image 34000 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 4World production of selected forest products (from Forest)
Image 5Form, leaves and reproductive structures of queen sago (Cycas circinalis) (from Tree)
Image 6Alnus glutinosa (from List of trees of Great Britain and Ireland)
Image 7Temperate rainforest in Tasmania's Hellyer Gorge (from Forest)
Image 8Forest in the Scottish Highlands (from Forest)
Image 9Since 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 10Yggdrasil, the World Ash of Norse mythology (from Tree)
Image 11Latvian Pine Forest in Ķegums Municipality (from Forest)
Image 12Rowan tree in Wicklow, Ireland (from List of trees of Great Britain and Ireland)
Image 13Burned forest on Thasos (from Forest)
Image 14A young red pine (Pinus resinosa) with spread of roots visible, as a result of soil erosion (from Tree)
Image 15Priest 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 16Cracked thorny skin of a Aesculus tree seed (from Tree)
Image 17A forest near Vinitsa, North Macedonia (from Forest)
Image 18Buds, leaves, flowers and fruit of oak (Quercus robur) (from Tree)
Image 19Share of forest area in total land area, top countries (2021) (from Forest)
Image 20Olive trees in Pakistan (from Trees of Pakistan)
Image 21A section of yew (Taxus baccata) showing 27 annual growth rings, pale sapwood and dark heartwood (from Tree)
Image 22Proportion and distribution of global forest area by climatic domain, 2020 (from Forest)
Image 23Share of land that is covered by forest (from Forest)
Image 24Dormant Magnolia bud (from Tree)
Image 25European larch (Larix decidua), a coniferous tree which is also deciduous (from Tree)
Image 26Wind dispersed seed of elm (Ulmus), ash (Fraxinus) and maple (Acer) (from Tree)
Image 27Northern beech (Fagus sylvatica) trunk in autumn (from Tree)
Image 28Selling firewood at a market (from Tree)
Image 29The Amazon rainforest alongside the Solimões River, a tropical rainforest. These forests are the most biodiverse and productive ecosystems in the world. (from Forest)
Image 30Fraxinus excelsior (from List of trees of Great Britain and Ireland)
Image 31Latex collecting from a rubber tree (Hevea brasiliensis) (from Tree)
Image 32Alleé of London plane trees (Platanus × acerifolia) in garden (from Tree)
Image 33People trees, by Pooktre (from Tree)
Image 34Trees in art: Weeping Willow, Claude Monet, 1918 (from Tree)
Image 35Recently stripped cork oak (Quercus suber) (from Tree)
Image 36Broadleaf forest in Bhutan (from Forest)
Image 37Buttress roots of the kapok tree (Ceiba pentandra) (from Tree)
Image 38Neem tree at Sant Nenuram Ashram (from Trees of Pakistan)
Image 39Spiny forest at Ifaty, Madagascar, featuring various Adansonia (baobab) species, Alluaudia procera (Madagascar ocotillo) and other vegetation (from Forest)
Image 40Informal upright style of bonsai on a juniper tree (from Tree)
Image 41Even, 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 42Conifers in the Swabian alps (from Tree)
Image 43The Daintree Rainforest (from Tree)
Image 44Palms and cycads as they might have appeared in the middle Tertiary (from Tree)
Image 45Redwood 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 46Malus sylvestris (from List of trees of Great Britain and Ireland)
Image 47Buds, leaves and reproductive structures of white fir (Abies alba) (from Tree)
Image 48Diagram 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 49Lepidodendron, an extinct lycophyte tree (from Tree)
Image 50Sugar maple (Acer saccharum) tapped to collect sap for maple syrup (from Tree)
Image 51Tall herbaceous monocotyledonous plants such as banana lack secondary growth, but are trees under the broadest definition. (from Tree)
Image 52Roof trusses made from softwood (from Tree)
Image 53Proportion of forest in protected areas, by region, 2020 (from Forest)
Image 54The General Sherman Tree, thought to be the world's largest by volume (from Tree)