1 : Tree
2 : Morphology
3 : Major tree genera
3.1 : Flowering plants (Magnoliophyta)
3.1.1 : Anacardiaceae (Cashew family)
Cashew, Anacardium occidentale
Mango, Mangifera indica
Pistachio, Pistacia vera
Lacquer tree, Toxicodendron verniciflua
Aquifoliaceae (Holly family)
Holly, Ilex species
Araliaceae (Ivy family)
Kalopanax, Kalopanax pictus
Betulaceae (Birch family)
Alder, Alnus species
Birch, Betula species
Bombacaceae (Baobab family; sometimes included in Malvaceae)
Baobab, Adansonia species
Silk-cotton tree, Bombax ceiba
Kapok, Ceiba pentandra
Durian, Durio zibethinus
Balsa, Ochroma lagopus
Cactaceae (Cactus family)
Saguaro, Carnegiea gigantea
Cornaceae (Dogwood family)
Dogwood, Cornus species
Corylaceae (Hazel family)
Hornbeam, Carpinus species
Hazel, Corylus species
Fabaceae (Pea family)
Honey locust, Gleditsia triacanthos
Black locust, Robinia pseudoacacia
Laburnum, Laburnum species
Pau Brasil, Brazilwood, Caesalpinia echinata
Fagaceae (Beech family )
Chestnut, Castanea species
Beech, Fagus species
Southern beech, Nothofagus species
Tanoak, Lithocarpus densiflorus
Oak, Quercus species
Fouquieriaceae (Boojum family)
Boojum, Fouquieria columnaris
Hamamelidaceae (Witch-hazel family)
Sweet-gum, Liquidambar species
Persian ironwood, Parrotia persica
Juglandaceae (Walnut family)
Walnut, Juglans species
Hickory, Carya species
Lauraceae (Laurel family)
Cinnamon Cinnamomum zeylanicum
Bay laurel Laurus nobilis
Avocado Persea americana
Lythraceae Loosestrife family
Crape myrtle Lagerstroemia species
Magnoliaceae (Magnolia family)
Tulip tree, Liriodendron species
Magnolia, Magnolia species
Malvaceae (including Tiliaceae) (Mallow family.)
Linden (Basswood, Lime), Tilia species
Meliaceae (Mahogany family)
Neem, Azadirachta indica (A. Juss)
Bead tree, Melia azedarach
Mahogany, Swietenia mahagoni
Myristicaceae (Nutmeg family)
Nutmeg, Mysristica fragrans
Myrtaceae (Myrtle family )
Eucalyptus, Eucalyptus species
Myrtle, Myrtus species
Guava, Psidium guajava
Nyssaceae: a Dove tree in flower
Nyssaceae (Tupelo family; sometimes included in Cornaceae)
Tupelo, Nyssa species
Dove tree, Davidia involucrata
Oleaceae (Olive family)
Olive, Olea europaea
Ash, Fraxinus species
Platanaceae (Plane family)
Plane, Platanus species
Rhizophoraceae (Mangrove family)
Red Mangrove, Rhizophora mangle
Rosaceae (Rose family)
Rowan, Sorbus species
Hawthorn, Crataegus species
Pear, Pyrus species
Apple, Malus species
Almond, Prunus dulcis
Peach, Prunus persica
Plum, Prunus domestica
Cherry, Prunus species
Rubiaceae (Bedstraw family)
Coffee, Coffea arabica
Rutaceae (Rue family)
Orange, Citrus aurantium
Lemon, Citrus limon
Cork-tree, Phellodendron species
Euodia, Tetradium species
Salicaceae (Willow family)
Aspen, Populus species
Poplar, Populus species
Willow, Salix species
Sapindaceae (including Aceraceae, Hippocastanaceae) (Soapberry family)
Maple, Acer species
Buckeye, Horse-chestnut, Aesculus species
Mexican buckeye, Ungnadia speciosa
Lychee, Litchi sinensis
Golden rain tree, Koelreuteria paniculata
Sapotaceae family
Tambalacoque, or dodo tree, Sideroxylon grandiflorum, previously Calvaria major
Simaroubaceae family
Tree of heaven, Ailanthus species
Sterculiaceae family
Cacao (cocoa), Theobroma cacao
Ulmaceae (Elm family)
Hackberry, Celtis species
Elm, Ulmus species
3.2 : Conifers
3.3 : Ginkgos
3.4 : Cycads
3.5 : Ferns
4 : Life stages
5 : Culture
6 : See also
:This article is about the biological organisms known as trees. For other meanings of the word see tree (disambiguation).
A tree can be defined as a large woody perennial plant. Though there is no set definition of size, it is generally at least 4.5 m (15 ft) high at maturity, and with branches supported on a single main stem. Trees are important components of the natural landscape and significant elements in landscaping. Compared with most other forms of plants, trees are long-lived. A few species of trees grow to over 100 m (300 ft) tall and some live for several millennia.
Morphology
The component parts of a tree are the roots, trunk(s), branches, twigs and leaves. Tree stems consist mainly of support and transport tissues (xylem and phloem). In fact, wood consists of xylem cells, and the bark is primarily made of phloem. As a tree grows, it creates growth rings, which can be counted in temperate climates to determine the age of the tree, and used to date cores or even lumber taken from trees in the past, using the science of dendrochronology. The roots of a tree are generally embedded in earth, providing anchorage for the above-ground biomass and absorbing water and nutrients from the soil. Above ground, the trunk gives height to the leaf-bearing branches, aiding in competition with other plant species for sunlight. In many trees the arrangement of the branches optimize exposure of the leaves to sunlight.
Not all trees have the plant organs mentioned above. For examples: most palms are not branched, the saguaro cactus of North America has no functional leaves, tree ferns do not have bark, etc. Based on their rough shape and size, all of these are nonetheless generally regarded as trees. Indeed, sometimes size is the most important consideration. A plant form that is similar to a tree, but generally having smaller, multiple trunks and/or branches that arise near the ground, is called a shrub. However, no sharp differentiation between shrubs and trees is possible. Given their small size, Bonsai plants would not technically be 'trees', but one should not confuse reference to the form of a species with the size or shape of individual specimens. A spruce seedling does not fit the definition of a tree, but all spruces are trees. Bamboos by contrast, do show most of the characteristics of trees, yet are perhaps strangely rarely called trees.
A small group of trees growing together is called a grove or copse, and a landscape covered by a large area of trees is called a forest. Several biotopes are defined largely by the trees that inhabit them, for example, rainforest and taiga; see ecozones. Large, but scattered trees with grassland (usually grazed or burned over periodically) in between is called savanna.
Major tree genera
Trees occur in many diverse families of plants, and thus show a wide variety of leaf types and shapes, bark, flowers, fruit, etc. The earliest trees were probably tree ferns, which grew in vast forests. Later the conifers, ginkgos, cycads and other gymnosperms appeared. Most species of trees today are flowering plants and conifers. The list below gives some examples of well known trees and how they are typically classified.
Flowering plants (Magnoliophyta) ">
====Dicotyledons (Magnoliopsida)Anacardiaceae_(Cashew_family)
- _Cashew,_''Anacardium_occidentale''
- _Mango,_''Mangifera_indica''
- _Pistachio,_''Pistacia_vera''
- _[[Toxicodendron|Lacquer_tree]],_''Toxicodendron_verniciflua''
- _Fabaceae_(Pea_family)
- _[[Honey_locust]],_''Gleditsia_triacanthos''
- _[[Black_locust]],_''Robinia_pseudoacacia''
- _Laburnum,_Laburnum_species
- _[[Caesalpinia_echinata|Pau_Brasil]],_Brazilwood,_''Caesalpinia_echinata''
- _Fouquieriaceae_([[Boojum_tree|Boojum]]_family)
- _[[Boojum_tree|Boojum]],_''Fouquieria_columnaris''
- _Lauraceae_([[Bay_laurel|Laurel]]_family)
- _Cinnamon_''Cinnamomum_zeylanicum''
- _[[Bay_laurel]]_''Laurus_nobilis''
- _Avocado_''Persea_americana''
''Nyssaceae:_a_[[Dove_tree]]_in_flower''
_
- _Rutaceae_(Rue_family)
- _[[Orange_(fruit)|Orange]],_''Citrus_aurantium''
- _Lemon,_''Citrus_limon''
- _Cork-tree,_Phellodendron_species
- _Euodia,_Tetradium_species
- _Sapotaceae_family
- _Tambalacoque,_or_''dodo_tree'',_''Sideroxylon_grandiflorum'',_previously_''Calvaria_major''
- _Simaroubaceae_family
- _[[Ailanthus|Tree_of_heaven]],_Ailanthus_species
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Monocotyledons (Liliopsida)====
- Note that Banana 'trees' are not actually trees, as they are not woody nor perennial.
Conifers_" id=" Conifers ">
Ginkgos_" id=" Ginkgos ">
Cycads_" id=" Cycads ">
Ferns_" id=" Ferns ">
Life stages
The life cycles of trees, especially conifers, are divided into the following stages in forestry for survey and documentation purposes:
# Seed
# Seedling: the above ground part of the embryo that sprout from the seed
# Sapling: After the seedling reaches 1m tall, and until it reaches 7cm in stem diameter
# Pole: young trees from 7-30cm diameter
# Mature tree: over 30cm diameter, reproductive years begin
# Old tree: dominate old growth forest; height growth slows greatly, with majority of productivity in seed production
# Overmature: dieback and decay become common
# Snag: standing dead wood
# Log/debris: fallen dead wood
Tree diameters are measured at height of between 1.3-1.5m above the highest point on the ground at its base. The 7cm diameter definition is economically based, from the smallest saleable stem size (for paper production, etc), and the 30cm diameter is the smallest base diameter for sawlogs. Each stage may be uniquely perceptive to different pathogens and suitable for especially adapted arboreal animals.
Culture
Trees often serve as important symbols in mythologies and religions. Examples are Yggdrasil in the Norse Mythology, the Christmas Tree that is derived from Germanic mythology, the Tree of Knowledge of Judaism and Christianity, and the Bodhi tree in Buddhism. In some religions, such as Hinduism, trees are said to be the homes of tree spirits.
See also
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