''Empetrum'' is a genus of three species of dwarf evergreen

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 in the heath family,

Ericaceae The Ericaceae () are a Family (biology), family of flowering plants, commonly known as the heath or heather family, found most commonly in acidic and infertile growing conditions. The family is large, with about 4,250 known species spread acros ...

. They are commonly known as crowberries and bear edible fruit. Species of ''Empetrum'' include: '' E. nigrum'' (crowberry) and its

tetraploid Polyploidy is a condition in which the cells of an organism have more than two paired sets of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two complete sets of chromosomes, one fro ...

subspecies ''E. nigrum'' ssp. ''hermaphroditum'', '' E. eamesii'' and '' E. rubrum''.

Description

All three species are evergreen mat forming shrubs, with small, light green needle-like

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

long. The

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

s are small and either bisexual or

dioecious Dioecy ( ; ; adj. dioecious, ) is a characteristic of certain species that have distinct unisexual individuals, each producing either male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is ...

. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

is a fairly dry

berry A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit although many pips or seeds may be present. Common examples of berries in the cul ...

. The plant has slender, wiry, spreading branches covered with short, narrow, stiff leaves, the margins of which are recurved so as to form a hollow cylinder concealing the hairy under face of the leaf, which protects against excessive loss of water from the leaf.

Taxonomy

The genus and related ones such as ''

Ceratiola ''Ceratiola'' is a genus of flowering plants with a single species, ''Ceratiola ericoides'', a shrub endemic to the Southeastern United States. Names ''C. ericoides'' is commonly known as Florida rosemary, sand heath, scrub rosemary, or sandhill ...

'' and ''

Corema ''Corema'' is a genus of two species of flowering plants in the family Ericaceae. They are dioecious small shrubs. Species * '' Corema album'' (L.) D. Don ex Steud. '' Corema album'' is also known for it common name ''Camarinha'' or Portuguese ...

'' were for most of the 20th century classified in their own family Empetraceae, but molecular data, leaf morphology, and other considerations point to their inclusion in the

(specifically, as a tribe within the subfamily

Ericoideae Ericoideae is a subfamily of Ericaceae, containing nineteen genera, and 1,790 species, the largest of which is ''Rhododendron'', followed by Erica. The Ericoideae bear spiral leaves with flat laminae. The pedicel is articulated and the flowers a ...

). This tribe does share a number of distinctive morphological features, which seem to be associated with

wind pollination Anemophily or wind pollination is a form of pollination whereby pollen is distributed by wind. Almost all gymnosperms are anemophilous, as are many plants in the order Poales, including grasses, sedges, and rushes. Other common anemophilous plan ...

. Species of ''Empetrum'' include: '' E. nigrum'' (crowberry or black crowberry) and its

subspecies ''E. nigrum'' ssp. ''hermaphroditum'', Stace, C. A. (2010) ''New Flora of the British Isles'', 3rd edition. Cambridge University press. . pp. 525 '' E. eamesii'' and '' E. rubrum''.

Distribution and habitat

They are commonly found in the Northern Hemisphere, from

temperate In geography, the temperate climates of Earth occur in the middle latitudes (approximately 23.5° to 66.5° N/S of the Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ran ...

subarctic The subarctic zone is a region in the Northern Hemisphere immediately south of the true Arctic, north of hemiboreal regions and covering much of Alaska, Canada, Iceland, the north of Fennoscandia, Northwestern Russia, Siberia, and the Cair ...

climates, and also in the Southern

Andes The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the List of longest mountain chains on Earth, longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range ...

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

and on the

South Atlantic The Atlantic Ocean is the second largest of the world's five oceanic divisions, with an area of about . It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for ...

islands of

South Georgia South Georgia is an island in the Atlantic Ocean, South Atlantic Ocean that is part of the British Overseas Territories, British Overseas Territory of South Georgia and the South Sandwich Islands. It lies around east of the Falkland Islands. ...

, the Falklands and

Tristan da Cunha Tristan da Cunha (), colloquially Tristan, is a remote group of volcano, volcanic islands in the South Atlantic Ocean. It is one of three constituent parts of the British Overseas Territories, British Overseas Territory of Saint Helena, Ascensi ...

. The typical habitat is on moorlands,

tundra In physical geography, a tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. There are three regions and associated types of tundra: #Arctic, Arctic, Alpine tundra, Alpine, and #Antarctic ...

muskeg Muskeg (; ; , lit. ''moss bog'') is a peat-forming ecosystem found in several northern climates, most commonly in Arctic and boreal ecosystem, boreal areas. Muskeg is approximately synonymous with bogland, bog or peatland, and is a standard te ...

and

spruce A spruce is a tree of the genus ''Picea'' ( ), a genus of about 40 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal ecosystem, boreal (taiga) regions of the Northern hemisphere. ''Picea'' ...

forests. They are also often found in areas of coastal exposure on the

sand dunes A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat ...

and dune slacks.

Uses

The vitamin content of crowberries is low, as is also the concentration of volatile liquids, the lack of which makes them almost odorless. The acidity is lower than is typically encountered in forest berries. In subarctic areas, ''Empetrum'' has been a vital addition to the diet of the

Inuit Inuit (singular: Inuk) are a group of culturally and historically similar Indigenous peoples traditionally inhabiting the Arctic and Subarctic regions of North America and Russia, including Greenland, Labrador, Quebec, Nunavut, the Northwe ...

and the

Sami Acronyms * SAMI, ''Synchronized Accessible Media Interchange'', a closed-captioning format developed by Microsoft * Saudi Arabian Military Industries, a government-owned defence company * South African Malaria Initiative, a virtual expertise ne ...

. After waning popularity, the crowberry is regaining its reputation as an edible berry. It provides a steady crop and the gathering is relatively easy. The high concentration of anthocyanin pigment can be used as a natural food dye. The Dena'ina (Tanaina) harvest it for food, sometimes storing in quantity for winter, and like it mixed with lard or oil. They keep well in a cool place without any special preparation. The berries are usually collected in the fall of the year but if not picked they may persist on the plant and can be picked in the spring. The Inuit and Native Americans mix them with other berries, especially the blueberry. Cooking enhances the flavor. They make good pie and jelly. The leaves and stems are used in Dena'ina medicine for diarrhea and stomach problems; they are boiled or soaked in hot water, and the strained liquid drunk. In Dena'ina plantlore in the Outer and Upper Inlet area of Lake Clark, the root is also used as a medicine, being used to remove a growth on an eye and to heal sore eyes. The roots are boiled and the eyes are washed with the strained, cooled tea, to which a little sugar may be added. Crowberries are also occasionally grown as

ornamental plant Ornamental plants or ''garden plants'' are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars th ...

s in rockeries, notably the yellow-foliage

cultivar A cultivar is a kind of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and which retains those traits when Plant propagation, propagated. Methods used to propagate cultivars include division, root a ...

''Empetrum nigrum'' 'Lucia'.

References

External links