A shrub or bush is a small- to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. They are distinguished from trees by their multiple stems and shorter height, less than 6 m-10 m (20 ft–33 ft) tall. Small shrubs, less than 2 m (6.6 ft) tall are sometimes termed subshrubs.
Shrubs are perennial woody plants, and therefore have persistent woody stems above ground (compare with herbaceous plants). Usually shrubs are distinguished from trees by their height and multiple stems. Some shrubs are deciduous (e.g. hawthorn) and others evergreen (e.g. holly). Ancient Greek philosopher Theophrastus divided the plant world into trees, shrubs and herbs.
Some definitions state that a shrub is less than 6 m and tree is over 6 m. Others use 10 m as the cut off point. Many species of tree may not reach this mature height because of less than ideal growing conditions, and resemble a shrub sized plant. However such species have the potential to grow taller under the ideal growing conditions for that plant.
Most definitions characterize shrubs as possessing multiple stems with no main trunk. This is because the stems have branched below ground level. There are exceptions to this, with some shrubs having main trunks, but these tend to be very short and divide into multiple stems close to ground level. Many trees can grow in multiple stemmed forms also, such as oak or ash.
An area of cultivated shrubs in a park or a garden is known as a shrubbery. When clipped as topiary, suitable species or varieties of shrubs develop dense foliage and many small leafy branches growing close together. Many shrubs respond well to renewal pruning, in which hard cutting back to a "stool" results in long new stems known as "canes". Other shrubs respond better to selective pruning to reveal their structure and character.
Shrubs in common garden practice are generally considered broad-leaved plants, though some smaller conifers such as mountain pine and common juniper are also shrubby in structure. Species that grow into a shrubby habit may be either deciduous or evergreen.
In botany and ecology, a shrub is more specifically used to describe the particular physical structural or plant life-form of woody plants which are less than 8 metres (26 ft) high and usually have many stems arising at or near the base. For example, a descriptive system widely adopted in Australia is based on structural characteristics based on life-form, plus the height and amount of foliage cover of the tallest layer or dominant species.
For shrubs 2–8 metres (6.6–26.2 ft) high the following structural forms are categorized:
For shrubs less than 2 metres (6.6 ft) high the following structural forms are categorized:
Those marked with * can also develop into tree form.
... Examples of subshrubs include candytuft, lavender, and rosemary. These broad definitions are ...
Basal shoots, root sprouts, adventitious shoots, and suckers are words for various kinds of shoots that grow from adventitious buds on the base of a tree or shrub, or from adventitious buds on its roots. Shoots that grow from buds on the base of a tree or shrub are denominated "basal shoots"; these are distinguished from shoots that grow from adventitious buds on the roots of a tree or shrub, which are denominated "root sprouts". A plant that produces root sprouts is described as surculose. Although a product of adventitious buds on a plant, water sprouts are distinct from basal shoots and root sprouts. They are colloquially yet incorrectly denominated "suckers", which word colloquially denominates basal shoots and root sprouts. Water sprouts occur on the above ground stem, branches, or both of trees and shrubs, well above the base of the plant and its roots, where adventitious buds can produce basal shoots and root sprouts, respectively.Camellia sinensis
Camellia sinensis is a species of evergreen shrub or small tree whose leaves and leaf buds are used to produce tea. It is of the genus Camellia (Chinese: 茶花; pinyin: Cháhuā, literally: "tea flower") of flowering plants in the family Theaceae. Common names include "tea plant", "tea shrub", and "tea tree" (not to be confused with Melaleuca alternifolia, the source of tea tree oil, or Leptospermum scoparium, the New Zealand Tea Tree).
Camellia sinensis var. sinensis and Camellia sinensis var. assamica, are two major varieties grown today. White tea, yellow tea, green tea, oolong, dark tea (which includes pu-erh tea) and black tea are all harvested from one or the other, but are processed differently to attain varying levels of oxidation. Kukicha (twig tea) is also harvested from Camellia sinensis, but uses twigs and stems rather than leaves.Deserts and xeric shrublands
Deserts and xeric shrublands are a habitat type defined by the World Wide Fund for Nature. Deserts and xeric shrublands form the largest terrestrial biome, covering 19% of Earth's land surface area.Ecoregions in this habitat type vary greatly in the amount of annual rainfall they receive, usually less than 250 millimetres (10 in) annually. Generally evaporation exceeds rainfall in these ecoregions. Temperature variability is also diverse in these lands. Many deserts, such as the Sahara, are hot year-round but others, such as Asia's Gobi, become quite cold in winter.Temperature extremes are a characteristic of most deserts. Searing daytime heat gives way to cold nights because there is no insulation provided by humidity and cloud cover. The diversity of climatic conditions,though quite harsh, supports a rich array of habitats. Many of these habitats are ephemeral in nature, reflecting the paucity and seasonality of available water.Woody-stemmed shrubs and plants characterize vegetation in these regions. Above all, these plants have evolved to minimize water loss. Animal biodiversity is equally well adapted and quite diverse.Genisteae
Genisteae is a tribe of trees, shrubs and herbaceous plants in the subfamily Faboideae of the legume family Fabaceae. It includes a number of well-known plants including broom, lupine (lupin), gorse and laburnum.
The tribe's greatest diversity is in the Mediterranean, and most genera are native to Europe, Africa, the Canary Islands, India and southwest Asia. However, the largest genus, Lupinus, is most diverse in North and South America. Anarthrophytum and Sellocharis are also South American and Aryrolobium ranges into India.Great Basin Desert
The Great Basin Desert is part of the Great Basin between the Sierra Nevada and the Wasatch Range. The desert is a geographical region that largely overlaps the Great Basin shrub steppe defined by the World Wildlife Fund, and the Central Basin and Range ecoregion defined by the U.S. Environmental Protection Agency and United States Geological Survey. It is a temperate desert with hot, dry summers and snowy winters. The desert spans a large part of the state of Nevada, and extends into western Utah, eastern California, and Idaho. The desert is one of the four biologically defined deserts in North America, in addition to the Mojave, Sonoran, and Chihuahuan Deserts.Basin and range topography characterizes the desert: wide valleys bordered by parallel mountain ranges generally oriented north-south. There are more than 33 peaks within the desert with summits higher than 9,800 feet (3,000 m), but valleys in the region are also high, most with elevations above 3,900 feet (1,200 m). The biological communities of the Great Basin Desert vary according to altitude: from low salty dry lakes, up through rolling sagebrush valleys, to pinyon-juniper forests. The significant variation between valleys and peaks has created a variety of habitat niches, which has in turn led to many small, isolated populations of genetically unique plant and animal species throughout the region. According to Grayson, more than 600 species of vertebrates live in the floristic Great Basin, which has a similar areal footprint to the ecoregion. Sixty-three of these species have been identified as species of conservation concern due to contracting natural habitats (for example, Centrocercus urophasianus, Vulpes macrotis, Dipodomys ordii, and Phrynosoma platyrhinos).The ecology of the desert varies across geography, also. The desert’s high elevation and location between mountain ranges influences regional climate: the desert formed by the rain shadow of the Sierra Nevada that blocks moisture from the Pacific Ocean, while the Rocky Mountains create a barrier effect that restricts moisture from the Gulf of Mexico. Different locations in the desert have different amounts of precipitation, depending on the strength of these rain shadows. The environment is influenced by Pleistocene lakes that dried after the last ice age: Lake Lahontan and Lake Bonneville. Each of these lakes left different amounts of salinity and alkalinity.Lantana
Lantana is a genus of about 150 species of perennial flowering plants in the verbena family, Verbenaceae. They are native to tropical regions of the Americas and Africa but exist as an introduced species in numerous areas, especially in the Australian-Pacific region. The genus includes both herbaceous plants and shrubs growing to 0.5–2 m (1.6–6.6 ft) tall. Their common names are shrub verbenas or lantanas. The generic name originated in Late Latin, where it refers to the unrelated Viburnum lantana.Lantana's aromatic flower clusters (called umbels) are a mix of red, orange, yellow, or blue and white florets. Other colors exist as new varieties are being selected. The flowers typically change color as they mature, resulting in inflorescences that are two- or three-colored.
"Wild lantanas" are plants of the unrelated genus Abronia, usually called "sand-verbenas".Lignotuber
A lignotuber is a woody swelling of the root crown possessed by some plants as a protection against destruction of the plant stem, such as by fire. The crown contains buds from which new stems may sprout, as well as stores of starch that can support a period of growth in the absence of photosynthesis. The term "lignotuber" was coined in 1924 by Australian botanist Leslie R. Kerr.
Plants possessing lignotubers include Eucalyptus marginata (Jarrah), Eucalyptus brevifolia (snappy gum) and Eucalyptus ficifolia (scarlet gum) all of which can have lignotubers ten feet (3 meters) wide and three feet (one meter) deep as well as most mallees, and many Banksia species. Lignotubers develop from the cotyledonary bud in seedlings of several oak species including cork oak Quercus suber, but do not develop in several other oak species, and are not apparent in mature cork oak trees.The largest known lignotubers (also called "root collar burls") are those of the Coast Redwood (Sequoia sempervirens) of central and northern California and extreme southwestern Oregon. A lignotuber washed into Big Lagoon (30 miles (48 km) north of Eureka, California) by the full gale storm of 1977 was 41 feet (12.5 meters) in diameter and about half as tall and estimated to weigh 525 short tons (476.3 metric tonnes). The largest dicot lignotubers are those of the Chinese Camphor Tree, or Kusu (Cinnamomum camphora) of Japan, China and the Koreas. Ones at the Vergelegan Estate in Cape Town, South Africa which were planted in the late 1600s have muffin-shaped lignotubers up to six feet (2 meters) high and about thirty feet (9 meters) in diameter. Perhaps the largest lignotuber in Australia would be that of "Old Bottle Butt", a Red Bloodwood Tree (Corymbia gummifera) near Wauchope, New South Wales which has a lignotuber about eight feet (2.5 meters) in height, and seventeen feet thick (16.3 meters circumference) at breast height. Many plants with lignotubers grow in a shrubby habit, but with multiple stems arising from the lignotuber. The term lignotuberous shrub is used to describe this habit.Maquis shrubland
Maquis (French) or macchia (Italian: macchia mediterranea) is a shrubland biome in the Mediterranean region, typically consisting of densely growing evergreen shrubs.Mediterranean forests, woodlands, and scrub
Mediterranean forests, woodlands, and scrub is a biome defined by the World Wide Fund for Nature. The biome is generally characterized by dry summers and rainy winters, although in some areas rainfall may be uniform. Summers are typically hot in low-lying inland locations but can be cool near colder seas. Winters are typically mild to cool in low-lying locations but can be cold in inland and higher locations. All these ecoregions are highly distinctive, collectively harboring 10% of the Earth's plant species.Northwestern Himalayan alpine shrub and meadows
The Northwestern Himalayan alpine shrub and meadows is a montane grasslands and shrublands ecoregion of the elevations of the northwestern Himalaya of China, India, and Pakistan.Rhacophoridae
The Rhacophoridae are a family of frogs which occur in tropical sub-Saharan Africa, South India and Sri Lanka, Japan; northeastern India to eastern China south through the Philippines and Greater Sundas, and Sulawesi. They are commonly known as shrub frogs, or more ambiguously as "moss frogs" or "bush frogs". Some Rhacophoridae are called "tree frogs". Among the most spectacular members of this family are numerous "flying frogs".
Although a few groups are primarily terrestrial, rhacophorids are predominantly treefrogs which are arboreal. Mating frogs, while in amplexus, hold on to a branch, and beat their legs to form a foam. The eggs are laid in the foam and covered with seminal fluid before the foam hardens into a protective casing. In some species, this is done in a large group. The foam is laid above a water source so the tadpoles fall into the water once they hatch.The species within this family vary in size from 1.5 to 12 cm (0.59 to 4.72 in). Like other arboreal frogs, they have toe discs, and those of the genus Chiromantis have two opposable fingers on each hand. This family also contains the Old World flying frogs, including Wallace's flying frog (Rhacophorus nigropalmatus). These frogs have extensive webbing between their forelimbs and hindlimbs, allowing them to glide through the air.Shrub, California
Shrub is an unincorporated community in El Dorado County, in the U.S. state of California. It is located on the Southern Pacific Railroad 2.5 miles (4 km) north-northeast of Latrobe, at an elevation of 1043 feet (318 m).Shrub swamp
Shrub swamps — also called scrub swamps or buttonbush swamps — are a type of freshwater wetland ecosystem occurring in areas too wet to become swamps (“true” or freshwater swamp forest), but too dry or too shallow to become marshes. They are often considered transitional (“mid-successional”) between wet meadows or fens and conifer or hardwood swamps.
By some classifications, shrub swamps must have at least 50% shrub cover and less than 20% tree cover. Other definitions specify large shrubs with small trees less than 35 feet in height. Creation of shrub swamps often follows a catastrophic event in a forested swamp (flood, cutting, fire, or windstorm). Another route of development is via drained meadows and fens which progress to shrub swamps as a transitional state to forested swamps.Shrubland
Shrubland, scrubland, scrub, brush, or bush is a plant community characterised by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It may be the mature vegetation type in a particular region and remain stable over time, or a transitional community that occurs temporarily as the result of a disturbance, such as fire. A stable state may be maintained by regular natural disturbance such as fire or browsing. Shrubland may be unsuitable for human habitation because of the danger of fire. The term was coined in 1903.Shrubland species generally show a wide range of adaptations to fire, such as heavy seed production, lignotubers, and fire-induced germination.Subshrub
A subshrub (Latin suffrutex) or dwarf shrub is a short woody plant. Prostrate shrub is a related term. "Subshrub" is often used interchangeably with "bush".Because the criteria are matters of degree rather than of kind, the definition of a subshrub is not sharply distinguishable from that of a shrub; examples of reasons for describing plants as subshrubs include ground-hugging stems or low growth habit. Subshrubs may be largely herbaceous, with overwintering perennial woody growth much lower-growing than deciduous summer growth. Some plants described as subshrubs are only weakly woody and some persist for only for a few years; others however, such as Oldenburgia paradoxa live indefinitely, rooted in rocky cracks.
Small, low shrubs such as lavender, periwinkle, and thyme, and many members of the family Ericaceae, such as cranberries and small species of Erica, are often classed as subshrubs.Tropical and subtropical grasslands, savannas, and shrublands
Tropical and subtropical grasslands, savannas, and shrublands is a terrestrial habitat type defined by the World Wide Fund for Nature.. The biome is dominated by grass and/or shrubs located in semi-arid to semi-humid climate regions of subtropical and tropical latitudes.Vaccinium vitis-idaea
Vaccinium vitis-idaea (lingonberry, partridgeberry, mountain cranberry or cowberry) is a short evergreen shrub in the heath family that bears edible fruit, native to boreal forest and Arctic tundra throughout the Northern Hemisphere from Eurasia to North America. Lingonberries are picked in the wild and used to accompany a variety of dishes in Northern Baltoscandia and Russia. Commercial cultivation is undertaken in the U.S. Pacific Northwest and in many other regions of the world.Witch-hazel
Witch-hazels or witch hazels (Hamamelis, ) are a genus of flowering plants in the family Hamamelidaceae, with four species in North America (H. mexicana, H. ovalis, H. virginiana, and H. vernalis), and one each in Japan (H. japonica) and China (H. mollis). The North American species are occasionally called winterbloom.Worcester Shrub Hill railway station
Worcester Shrub Hill railway station is one of two railway stations serving the city of Worcester in Worcestershire, England. It is managed by West Midlands Trains, operating here under the West Midlands Railway brand, and it is also served by Great Western Railway. The platform 2B waiting room of Worcester Shrub Hill is Grade II* listed and reopened in 2015 after a ten-year refurbishment project.
The city's other station, Worcester Foregate Street, is situated in the city centre; Shrub Hill is situated to the east. A third station Worcestershire Parkway is currently being built just outside the city to the south-east.
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