Japanese Maple bark.

Bark of a Pine tree in Tecpan, Guatemala.

Bark is the outermost layer of stems and roots of woody plants such as trees. It overlays the wood and consists of three layers, the cork, the phloem, and the vascular cambium. Look up bark in Wiktionary, the free dictionary. ... Image File history File links Metadata Size of this preview: 800 × 600 pixelsFull resolution (3264 × 2448 pixels, file size: 2. ... Image File history File links Metadata Size of this preview: 800 × 600 pixelsFull resolution (3264 × 2448 pixels, file size: 2. ... Binomial name Acer palmatum Thunb. ... Image File history File linksMetadata Download high-resolution version (2304x1728, 1534 KB) Detail of the bark of a pine tree in Tecpan, Guatemala. ... Image File history File linksMetadata Download high-resolution version (2304x1728, 1534 KB) Detail of the bark of a pine tree in Tecpan, Guatemala. ... Stem showing internode and nodes plus leaf petiole and new stem rising from node. ... For other uses, see Root (disambiguation). ... A woody plant is a vascular plant that has a stem (or more than one stem) that is lignified to a high degree. ... The coniferous Coast Redwood, the tallest tree species on earth. ... For other uses, see Wood (disambiguation). ... Cork is a tissue found in some plants, which consists tightly packed dead cells. ... In vascular plants, phloem is the living tissue that carries organic nutrients, particularly sucrose, a sugar, to all parts of the plant where needed. ... The vascular cambium is a lateral meristem: The vascular cambium is the source of both the secondary xylem (inwards) and the secondary phloem (outwards), and hence is located between these tissues in the stem. ...

[edit] Botanic description

In young stems of woody plants like trees and shrubs and some perennial vines, the bark is made up of these tissues arranged from the outside surface to the inside: A broom shrub in flower A shrub or bush is a horticultural rather than strictly botanical category of woody plant, distinguished from a tree by its multiple stems and lower height, usually less than 6 m tall. ... Red Valerian, a perennial plant. ... This article or section does not cite any references or sources. ... Biological tissue is a collection of interconnected cells that perform a similar function within an organism. ...

• Cork - an external, secondary tissue impermeable to water and gases.
• Cork cambium - A layer of cells , normally one or two cell layers thick that is in a persistent meristematic state that produces cork.
• Phelloderm - (not always present) A layer of cells formed in some plants from the inner cells of the cork cambium (Cork is produced from the outer layer).
• Cortex - The primary tissue of stems and roots. In stems the cortex is between the epidermis layer and the phloem, in roots the inner layer is not phloem but the pericycle.
• Phloem - nutrient conducting tissue composed of sieve tube or sieve cells mixed with parenchyma and fibers.

In old stems the epidermal layer, cortex, and primary phloem become separated from the inner tissues by thicker formations of cork. Due to the thickening cork layer these cells die because they do not receive water and nutrients. This dead layer is the rough corky bark that forms around tree trunks and other stems. In smaller stems and on typically non woody plants, sometimes a secondary covering forms called the periderm, which is made up of cork cambian, cork and phelloderm. It replaces the dermal layer and acts as a covering much like the corky bark, it too is made up of mostly dead tissue. The skin on the potato is a periderm. Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell being used to describe the smallest unit of a living organism Cells in culture, stained for keratin (red) and DNA (green) The cell is the... Meristem is a type of embryonic tissue in plants consisting of unspecialized, youthful cells called meristematic cells and found in areas of the plant where growth is or will take place, this is in roots and shoots. ... Stem showing internode and nodes plus leaf petiole and new stem rising from node. ... Found in the stele of plants, the pericycle is a cylinder of parenchyma cells that lies just inside the endodermis. ... A nutrient is either a chemical element or compound used in an organisms metabolism or physiology. ... Parenchyma is a term used to describe a bulk of a substance. ... It has been suggested that this article or section be merged into Bark. ...

Definitions of the term can vary. In another usage, bark consists of the dead and protective tissue found on the outside of a woody stem, and does not include the vascular tissue.

The vascular cambium is the only part of a woody stem where cell division occurs. It contains undifferentiated cells that divide rapidly to produce secondary xylem to the inside and secondary phloem to the outside. Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem. ... This does not adequately cite its references or sources. ... In vascular plants, xylem is one of the two types of transport tissue in plants, phloem being the other one. ... In vascular plants, phloem is the living tissue that carries organic nutrients, particularly sucrose, a sugar, to all parts of the plant where needed. ...

Along with the xylem, the phloem is one of the two tissues inside a plant that are involved with fluid transport. The phloem transports organic molecules (particularly sugars) to wherever they are needed. In vascular plants, xylem is one of the two types of transport tissue in plants, phloem being the other one. ... This article is about sugar as food and as an important and widely traded commodity. ...

[edit] Uses

Cork, sometimes confused with bark in colloquial speech, is the outermost layer of a woody stem, derived from the cork cambium. It serves as protection against damage, parasites and diseases, as well as dehydration and extreme temperatures. Cork can contain antiseptics like tannins. Some cork is substantially thicker, providing further insulation and giving the bark a characteristic structure, in some cases thick enough to be harvestable as cork product without killing the tree. Cork cambium is a tissue found in woody plants as part of the periderm. ... A parasite is an organism that spends a significant portion of its life in or on the living tissue of a host organism and which causes harm to the host without immediately killing it. ... This article is about the medical term. ... An antiseptic solution of Povidone-iodine applied to an abrasion Antiseptics (Greek αντί, against, and σηπτικός, putrefactive) are antimicrobial substances that are applied to living tissue/skin to reduce the possibility of infection, sepsis, or putrefaction. ... A bottle of tannic acid. ... For other uses, see Cork. ...

The bark of some trees is edible.

Among the commercial products made from bark are cork, cinnamon, quinine (from the bark of Cinchona) and aspirin (from the bark of willow trees). The bark of some trees notably oak (Quercus robur) is a source of tannic acid, which is used in tanning. For other uses, see Cork. ... Binomial name J.Presl Cassia (Chinese cinnamon) is also commonly called (and sometimes sold as) cinnamon. ... Quinine (IPA: ) is a natural white crystalline alkaloid having antipyretic (fever-reducing), anti-smallpox, analgesic (painkilling), and anti-inflammatory properties and a bitter taste. ... Species See text Cinchona L., is the name of a genus in Rubiaceae family, large evergreens that can grow over 10 metres tall. ... This article is about the drug. ... Species About 350, including: Salix acutifolia - Violet Willow Salix alaxensis - Alaska Willow Salix alba - White Willow Salix alpina - Alpine Willow Salix amygdaloides - Peachleaf Willow Salix arbuscula - Mountain Willow Salix arbusculoides - Littletree Willow Salix arctica - Arctic Willow Salix atrocinerea Salix aurita - Eared Willow Salix babylonica - Peking Willow Salix bakko Salix barrattiana... This article is about making hides into leather. ...

[edit] Gallery

Eucalypt bark Image File history File links Size of this preview: 800 × 534 pixelsFull resolution (1600 × 1067 pixels, file size: 1. ...

Acer capillipes (Red Snakebark Maple) Image File history File links Metadata Size of this preview: 400 × 600 pixelsFull resolution (2336 × 3504 pixels, file size: 3. ... Binomial name Maxim. ...

Monterey Pine bark Image File history File links Download high resolution version (1600x1600, 491 KB) Bark of Radiata Pine tree File links The following pages link to this file: Pine Bark ... Binomial name Pinus radiata D.Don Pinus radiata (family Pinaceae) is known in English as Monterey Pine in some parts of the world (mainly in the USA, Canada and the British Isles), and Radiata Pine in others (primarily Australia, New Zealand and Chile). ...

[edit] See also

Wikimedia Commons has media related to:

Bark

• Bark painting
• Bark beetle
• Trunk (botany)

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