The chestnuts are the deciduous trees and shrubs in the genus Castanea, in the beech family Fagaceae. The name also refers to the edible nuts they produce. They are native to temperate regions of the Northern Hemisphere.
The American chestnut is a large, fast-growing deciduous tree of the beech family native to eastern North America. As is true of all species in the genus Castanea, the American chestnut produces burred fruit with edible nuts. The American chestnut was one of the most important forest trees throughout its range.
The pathogenic fungus Cryphonectria parasitica is a member of the Ascomycota. This necrotrophic fungus is native to East Asia and South East Asia and was introduced into Europe and North America in the early 1900s. The fungus spread rapidly and caused significant tree loss in both regions.
Phytophthora is a genus of plant-damaging oomycetes, whose member species are capable of causing enormous economic losses on crops worldwide, as well as environmental damage in natural ecosystems. The cell wall of Phytophthora is made up of cellulose. The genus was first described by Heinrich Anton de Bary in 1875. Approximately 210 species have been described, although 100–500 undiscovered Phytophthora species are estimated to exist.
Castanea pumila, commonly known as the Allegheny chinquapin, American chinquapin or dwarf chestnut, is a species of chestnut native to the southeastern United States. The native range is from Massachusetts and New York to Maryland and extreme southern New Jersey and southeast Pennsylvania south to central Florida, west to eastern Texas, and north to southern Missouri and Kentucky. The plant's habitat is dry sandy and rocky uplands and ridges mixed with oak and hickory to 1000 m elevation. It grows best on well-drained soils in full sun or partial shade.
Monilinia fructicola is a species of fungus in the order Helotiales. A plant pathogen, it is the causal agent of brown rot of stone fruits.
Alternaria alternata is a fungus causing leaf spots, rots, and blights on many plant parts, and other diseases. It is an opportunistic pathogen on over 380 host species of plant.
Botryosphaeria obtusa is a plant pathogen that causes frogeye leaf spot, black rot and cankers on many plant species. On the leaf it is referred to as frogeye leaf spot; this phase typically affects tree and shrubs. In fruit such as the apple, cranberry and quince, it is referred to as black rot, and in twigs and trunks it causes cankers.
Phytophthora × cambivora is a plant pathogen that causes ink disease in European chestnut trees. Ink disease, also caused by Phytophthora cinnamomi, is thought to have been present in Europe since the 18th century, and causes chestnut trees to wilt and die; major epidemics occurred during the 19th and 20th centuries. P. cinnamomi and P. × cambivora are now present throughout Europe since the 1990s. Ink disease has resurged, often causing high mortality of trees, particularly in Portugal, Italy, and France. It has also been isolated from a number of different species since the 1990s, including:
Monilinia laxa is a plant pathogen that is the causal agent of brown rot of stone fruits.
Lasiodiplodia theobromae is a plant pathogen with a very wide host range. It causes rotting and dieback in most species it infects. It is a common post harvest fungus disease of citrus known as stem-end rot. It is a cause of bot canker of grapevine. It also infects Biancaea sappan, a species of flowering tree also known as Sappanwood.
Porodaedalea pini, commonly known as the pine conk, is a species of fungus in the family Hymenochaetaceae. It is a plant pathogen that causes tree disease commonly known as "red ring rot" or "white speck". This disease, extremely common in the conifers of North America, decays tree trunks, rendering them useless for lumber. It is a rot of the heartwood. Signs of the fungus include shelf-shaped conks protruding from the trunks of trees. Spores produced on these conks are blown by the wind and infect other trees. Formal management of this disease is limited, and the disease is controlled primarily by cultural practices. Red ring rot is an important forest disturbance agent and plays a key role in habitat formation for several forest animals.
Diaporthales is an order of sac fungi.
Gnomonia fructicola is a fungal plant pathogen on strawberries causing leaf spot disease. It can overwinter on leaves and fruits of Fragaria spp. (Rosaceae), occasionally pathogenic on fruits causing strawberry stem-end rot. The causal organism has often been referred to as Gnomoniacomari, now considered Gnomoniopsiscomari. It occurs in Canada, Europe and U.S.A..
Dryocosmus kuriphilus is a species of gall wasp known by the common names chestnut gall wasp, Oriental chestnut gall wasp, and Asian chestnut gall wasp. It is native to China and it is known in many other parts of the world, particularly the Northern Hemisphere, as an introduced species and an invasive horticultural pest. It attacks many species of chestnut, including most cultivated varieties. It is considered the world's worst pest of chestnuts.
The Precoce Migoule is a chestnut hybrid, a natural cross between a European chestnut and a Japanese chestnut. It was discovered by J. Dufrenoy at the orchard of Migoule in Brive-la-Gaillarde. The tree is vigorous and erect growing with growth of a metre or more in a season if the conditions are right. It is a large sized chestnut tree with height reaching 20 m or more and 7.5-10 m wide. Trees start to bear after 3 to 5 years. Full nut production in 12 - 20 years depending on the location.
Marsol is a natural chestnut hybrid, a cross between a European chestnut and Japanese.
Comballe is a French traditional chestnut variety. In France, it is the variety with the largest production. This beautiful rustic nut of Ardèche origin has a bright, streaky chestnut colour. Its fine, sweet and fragrant flesh justifies the excellent taste reputation.
Castanea seguinii, called Seguin chestnut, Seguin's chestnut, or Chinese chinquapin, and in Chinese: 茅栗, mao li, is a species of chestnut native to south‑central and southeast China.
Gnomoniopsis smithogilvyi, known as the chestnut rot fungus, is a species of fungus in the family Gnomoniaceae. It causes chestnuts to rot, preventing their use as food.
