A thicket is a very dense stand of

tree 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, e.g., including only woody plants with secondary growth, only ...

s or tall

shrub A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...

s, often dominated by only one or a few

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

, to the exclusion of all others. They may be formed by species that shed large numbers of highly viable

seed In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...

s that are able to

germinate Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an flowering plant, angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the sp ...

in the shelter of the maternal plants. In some conditions, the formation or spread of thickets may be assisted by human disturbance of an area. Human disturbance and activity within thickets varies based on culture and location. Where a thicket is formed of briar (also spelled brier), which is a common name for any of a number of unrelated thorny plants, it may be called a briar patch. Plants termed briar include species in the genera ''Rosa'' (

Rose A rose is either a woody perennial plant, perennial flowering plant of the genus ''Rosa'' (), in the family Rosaceae (), or the flower it bears. There are over three hundred Rose species, species and Garden roses, tens of thousands of cultivar ...

), ''

Rubus ''Rubus'' is a large and diverse genus of flowering plants in the rose family, Rosaceae, subfamily Rosoideae, most commonly known as brambles. Fruits of various species are known as raspberries, blackberries, dewberries, and bristleberries. ...

'', and ''

Smilax ''Smilax'' is a genus of about 300–350 species, found in the tropics and subtropics worldwide. They are climbing flowering plants, many of which are woody and/or thorny, in the monocotyledon family (biology), family Smilacaceae, native through ...

''.

Characteristics

Thickets are characterized by dense plant life, a low closed canopy, deep shale-derived soil, and high levels of soil carbon and nitrogen. Plants present within a thicket generally reach a maximum of 4 to 6 meters in height. The boundaries between a thicket and its nearby

forest A forest is an ecosystem characterized by a dense ecological community, community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, ...

are defined by a lack of precipitation and overall dry environment within the thicket area, while forests receive higher levels of precipitation. Forests also do not experience as much

herbivory A herbivore is an animal anatomically and physiologically evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat n ...

and browsing in comparison to thickets. The thicket biome has been identified in Africa, Madagascar, Australia, North America, and South America. One of the most studied and well-recognized thickets is the Albany thicket biome, located in the Eastern Cape of South Africa. Due to their overlapping ranges and similarity of plant species, thicket biomes may be misidentified as being portions of

savannas A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterised by the trees being sufficiently widely spaced so that the Canopy (forest), canopy does not close. The open canopy allows sufficient li ...

. However, these areas can be differentiated through a thicket's lack of C4 grasses and relatively low fire exposure.

Significance and use

Ecological significance

While thickets tend to have a small number of plant species present, as they are often dominated by one species of tree or shrub, the biome provides ecological resources to a large group of species. Thickets frequently make up sections of the home ranges of native species, including ptarmigan and hares in the tundra, cheetahs and lions in Africa, and frogs and alligators in North America. In particular, a thicket's high plant density and resulting low visibility allows for predator species to succeed in tracking, stalking, and capturing their prey.

Societal significance

Especially within the Albany thicket biome, thickets have traditionally been used for raising domestic

livestock Livestock are the Domestication, domesticated animals that are raised in an Agriculture, agricultural setting to provide labour and produce diversified products for consumption such as meat, Egg as food, eggs, milk, fur, leather, and wool. The t ...

, although the popularity of doing so is declining over time. Recently, the primary human activity taking place in thickets is game hunting, both for recreational purposes and for

ecotourism Ecotourism is a form of nature-oriented tourism intended to contribute to the Ecological conservation, conservation of the natural environment, generally defined as being minimally impactful, and including providing both contributions to conserv ...

. The increase in game hunting within thickets has also led to the rise of manmade game farms, which has prompted discussion regarding the impact of game farms on the biome and its health. Conservationists and biologists pose concern about the decrease in biodiversity that game farms may create, especially when coupled with other anthropogenic threats to thickets such as land clearing and

urbanization Urbanization (or urbanisation in British English) is the population shift from Rural area, rural to urban areas, the corresponding decrease in the proportion of people living in rural areas, and the ways in which societies adapt to this change. ...

. Alternatively, farmers and many locals suggest that the formation of game farms is an effective manner in which to preserve land area and minimize human impact on a thicket.

References

Habitats Habitat Shrubs Plant common names {{habitat-stub