Prunus

Members of the genus can be deciduous or evergreen. A few species have spiny stems. The leaves are simple, alternate, usually lanceolate, unlobed, and often with nectaries on the leaf stalk along with stipules. The flowers are usually white to pink, sometimes red, with five petals and five sepals. Numerous stamens are present. Flowers are borne singly, or in umbels of two to six or sometimes more on racemes. The fruit is a fleshy drupe (a "prune") with a single relatively large, hard-coated seed (a "stone").[7]

Within the rose family Rosaceae, it was traditionally placed as a subfamily, the Amygdaloideae (incorrectly "Prunoideae"), but was sometimes placed in its own family, the Prunaceae (or Amygdalaceae). More recently, Prunus is thought to have evolved from within a much larger clade now called subfamily Amygdaloideae (incorrectly "Spiraeoideae").[2]

Eastern Hemisphere

Japanese cherry (Prunus serrulata) blossoms

Tibetan cherry (Prunus serrula) bark

• P. africana – African cherry
• P. apetala – clove cherry
• P. armeniaca – apricot
• P. avium – sweet cherry or wild cherry
• P. brigantina – Briançon apricot
• P. buergeriana – dog cherry
• P. campanulata – Taiwan cherry
• P. canescens – gray-leaf cherry
• P. cerasifera – cherry plum
• P. cerasoides – wild Himalayan cherry
• P. cerasus – sour cherry
• P. ceylanica
• P. cocomilia – Italian plum
• P. cornuta – Himalayan bird cherry
• P. davidiana – David's peach
• P. darvasica – Darvaz plum
• P. domestica – common plum
• P. dulcis – almond
• P. fruticosa – European dwarf cherry
• P. glandulosa – Chinese bush cherry
• P. grayana – Japanese bird cherry
• P. incana – willow-leaf cherry
• P. incisa – Fuji cherry
• P. jacquemontii – Afghan bush cherry
• P. japonica – Japanese bush cherry
• P. laurocerasus – cherry laurel
• P. lusitanica – Portugal laurel
• P. maackii – Manchurian cherry
• P. mahaleb – Mahaleb cherry
• P. mandshurica – Manchurian apricot
• P. maximowiczii – Korean cherry
• P. mume – Chinese plum
• P. nipponica – Japanese alpine cherry
• P. padus – bird cherry
• P. persica – peach
• P. pseudocerasus – Chinese sour cherry
• P. prostrata – mountain cherry
• P. salicina – Japanese plum
• P. sargentii – north Japanese hill cherry
• P. scoparia – mountain almond
• P. serrula – Tibetan cherry
• P. serrulata – Japanese cherry
• P. sibirica – Siberian apricot
• P. simonii – apricot plum
• P. speciosa – Oshima cherry
• P. spinosa – blackthorn, sloe
• P. ssiori – Hokkaido bird cherry
• P. subhirtella – winter-flowering cherry
• P. tenella – dwarf Russian almond
• P. tomentosa – Nanking cherry
• P. triloba – flowering plum
• P. turneriana – almondbark
• P. ursina – Bear's plum
• P. × yedoensis – Yoshino cherry
• P. zippeliana – big-leaf cherry (Chinese: 大叶桂樱)

Western Hemisphere

Black cherry (Prunus serotina) in bloom

• P. alabamensis – Alabama cherry
• P. alleghaniensis – Allegheny plum
• P. americana – American plum
• P. andersonii – desert peach
• P. angustifolia – Chickasaw plum
• P. brasiliensis
• P. buxifolia
• P. caroliniana – Carolina laurelcherry
• P. cortapico
• P. emarginata – bitter cherry
• P. eremophila – Mojave Desert plum
• P. fasciculata – wild almond
• P. fremontii – desert apricot
• P. geniculata – scrub plum
• P. gentryi
• P. gracilis – Oklahoma plum
• P. havardii – Havard's plum
• P. hortulana – Hortulan plum
• P. huantensis
• P. ilicifolia – hollyleaf cherry
• P. integrifolia
• P. maritima – beach plum
• P. mexicana – Mexican plum
• P. minutiflora – Texas almond
• P. murrayana – Murray's plum
• P. myrtifolia – West Indies cherry
• P. nigra – Canada plum
• P. occidentalis – western cherry laurel
• P. pensylvanica – pin cherry
• P. pleuradenia – Antilles cherry
• P. pumila – sand cherry
• P. rigida
• P. rivularis – creek plum
• P. serotina – black cherry
• P. subcordata – Klamath plum
• P. subcorymbosa
• P. texana – peachbush
• P. umbellata – flatwoods plum
• P. virginiana – chokecherry

The development sequence of a nectarine (P. persica) over a 7.5-month period, from bud formation in early winter to fruit ripening in midsummer

The genus Prunus includes the almond, the nectarine and peach, several species of apricots, cherries, and plums, all of which have cultivars developed for commercial fruit and nut production. The almond is not a true nut; the edible part is the seed. Other species are occasionally cultivated or used for their seed and fruit.

A number of species, hybrids, and cultivars are grown as ornamental plants, usually for their profusion of flowers, sometimes for ornamental foliage and shape, and occasionally for their bark.

Because of their considerable value as both food and ornamental plants, many Prunus species have been introduced to parts of the world to which they are not native, some becoming naturalised.

The Tree of 40 Fruit has 40 varieties grafted on to one rootstock.[15][16]

Species such as blackthorn (Prunus spinosa), are grown for hedging, game cover, and other utilitarian purposes.

The wood of some species (notably black cherry) is prized as a furniture and cabinetry timber, especially in North America.

Many species produce an aromatic gum from wounds in the trunk; this is sometimes used medicinally. Other minor uses include dye production.

Pygeum, a herbal remedy containing extracts from the bark of Prunus africana, is used as to alleviate some of the discomfort caused by inflammation in patients with benign prostatic hyperplasia.

Prunus species are food plants for the larvae of many Lepidoptera species (butterflies and moths).

Prunus species are included in the Tasmanian Fire Service's list of low flammability plants, indicating that it is suitable for growing within a building protection zone.[17]

Many species are cyanogenic; that is, they contain compounds called cyanogenic glucosides, notably amygdalin, which, on hydrolysis, yield hydrogen cyanide.[18] Although the fruits of some may be edible by humans and livestock (in addition to the ubiquitous fructivore of birds), seeds, leaves and other parts may be toxic, some highly so.[19] The plants contain no more than trace amounts of hydrogen cyanide, but on decomposition after crushing and exposure to air or on digestion, poisonous amounts may be generated. The trace amounts may give a characteristic taste ("bitter almond") with increasing bitterness in larger quantities, less tolerable to people than to birds, which habitually feed on specific fruits.

People are often encouraged to consume many fruits because they are rich in a variety of nutrients and phytochemicals that are supposedly beneficial to human health. The fruits of Prunus often contain many phytochemicals and antioxidants.[6][20][21] These compounds have properties that have been linked to preventing different diseases and disorders.[20][22][23] Research suggests that the consumption of these fruits reduces the risk of developing diseases such as cardiovascular diseases, cancer, diabetes, and other age-related declines.[22][23] Many factors can affect the levels of bioactive compounds in the different fruits of the genus Prunus, including the environment, season, processing methods, orchard operations, and postharvest management.[6]

Cherries are prone to gummosis.

Various Prunus species are winter hosts of the Damson-hop aphid, Phorodon humuli, which is destructive to hops Humulus lupulus just at the time of their maturity,[34] so plum trees should not be grown in the vicinity of hop fields.

Corking is the drying or withering of fruit tissue.[35] In stone fruit, it is often caused by a lack of boron and/or calcium.[36]

Gummosis is a nonspecific condition of stone fruits (peach, nectarine, plum, and cherry) in which gum is exuded and deposited on the bark of trees. Gum is produced in response to any type of wound – insect, mechanical injury, or disease.[37]

Apiosporina morbosa is a major fungal disease in the Northern Americas, with many urban centres running black knot fungus management programs.[38] This disease is best managed by physical removal of knot-bearing branches to prevent spore spread and immediate disposal of infected tissue.[38] Chemical treatment is not largely effective, as trees can easily be re-infected by neighbouring knots.

Laetiporus gilbertsoni (commonly sulfur shelf and chicken of the woods), is a serious cubic brown rot parasite which attacks certain species of decorative red-leaf plum trees in the genus Prunus on the Pacific coast of North America.[39][40]

The earliest known fossil Prunus specimens are wood, drupe, seed, and a leaf from the middle Eocene of the Princeton Chert of British Columbia, Canada.[41] Using the known age as calibration data, a partial phylogeny of some of the Rosaceae from a number of nucleotide sequences was reconstructed.[42] Prunus and its sister clade Maloideae (apple subfamily) has been suggested to have diverged 44.3 million years ago which is within the Lutetian, or older middle Eocene.[lower-alpha 3] Stockey and Wehr report: "The Eocene was a time of rapid evolution and diversification in Angiosperm families such as the Rosaceae ...."[41] The oldest fossil species is Prunus cathybrownae from the Klondike Mountain Formation.[43]

The Princeton finds are among a large number of angiosperm fossils from the Okanagan Highlands dating to the late early and middle Eocene. Crataegus is found at three locations: the McAbee Fossil Beds, British Columbia; the Klondike Mountain Formation around Republic, Washington, and the Allenby Formation around Princeton, British Columbia, while Prunus is found at those locations plus the Coldwater Beds of Quilchena, British Columbia and Chu Chua Formation around Chu Chua, British Columbia. A review of research on the Eocene Okanagan Highlands[44] reported that the Rosaceae were more diverse at higher altitudes. The Okanagan highlands formations date to as early as 52 mya, but the 44.3 mya date, which is approximate, depending on assumptions, might still apply. The authors state: "... the McAbee flora records a diverse early middle Eocene angiosperm-dominated forest."[44]^: 165

The Online Etymology Dictionary presents the customary derivations of plum[45] and prune[46] from Latin prūnum,[47] the plum fruit. The tree is prūnus;[48] and Pliny uses prūnus silvestris to mean the blackthorn. The word is not native Latin, but is a loan from Greek προῦνον (prounon), which is a variant of προῦμνον (proumnon),[49] origin unknown. The tree is προύμνη (proumnē).[50] Most dictionaries follow Hoffman, Etymologisches Wörterbuch des Griechischen, in making some form of the word a loan from a pre-Greek language of Asia Minor, related to Phrygian.

The first use of Prunus as a genus name was by Carl Linnaeus in Hortus Cliffortianus of 1737,[51] which went on to become Species Plantarum. In the latter, Linnaeus attributes the word to "Varr.", who it is assumed must be Marcus Terentius Varro.

Wikimedia Commons has media related to Prunus.

• "GRIN Species Records of Prunus". Beltsville, Maryland: USDA, ARS, National Genetic Resources Program. Germplasm Resources Information Network (GRIN) [Online Database]. National Germplasm Resources Laboratory. Retrieved 13 November 2009.
• "Our Cherries Collection — Prunus". Missouri Botanical Garden: Kemper Center for Home Gardening. 2001–2009. Retrieved 13 November 2009.
• Tree of 40 fruit website