The chestnut blight is a fungal disease caused by the sac fungus (Ascomycota), Cryphonectria parasitica (formerly Endothia parasitica). It was accidentally introduced to North America around 1900-1908, either in imported chestnut lumber or in imported chestnut trees, and by 1940, mature American chestnut trees had been made virtually extinct by the disease. Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms. ... Divisions Chytridiomycota Zygomycota Glomeromycota Ascomycota Basidiomycota Yellow fungus Fungus growing on a tree in Borneo A fungus (plural fungi) is a eukaryotic organism that digests its food externally and absorbs the nutrient molecules into its cells. ... Classes Archaeascomycetes Discomycetes Euascomycetes Hemiascomycetes Lecanoromycetes Neolectomycetes Pezizomycotina Pneumocystidomycetes Saccharomycotina Schizosaccharomycetes Taphrinomycetes Mitosporic Ascomycota Members of the Division Ascomycota are known as the Sac Fungi and are fungi that produce spores in a distinctive type of microscopic sporangium called an ascus (Greek for a bag or wineskin). This monophyletic grouping... Classes Arthoniomycetes Chaetothyriomycetes Dothideomycetes Eurotiomycetes Laboulbeniomycetes Lecanoromycetes Leotiomycetes Orbiliomycetes Pezizomycetes Sordariomycetes mitosporic Pezizomycotina Pezizomycotina is a subphylum of the Ascomycota and was previously called the Euascomycota. ... Orders Diaporthales Hypocreales Sordariomycetes is a class of the subphylum, Pezizomycotina, which includes ascomycetous fungi that generally produce their asci in perithecial fruiting bodies. ... In biology, binomial nomenclature refers to the formal method of naming species. ... Divisions Chytridiomycota Zygomycota Glomeromycota Ascomycota Basidiomycota Yellow fungus Fungus growing on a tree in Borneo A fungus (plural fungi) is a eukaryotic organism that digests its food externally and absorbs the nutrient molecules into its cells. ... Classes Archaeascomycetes Discomycetes Euascomycetes Hemiascomycetes Lecanoromycetes Neolectomycetes Pezizomycotina Pneumocystidomycetes Saccharomycotina Schizosaccharomycetes Taphrinomycetes Mitosporic Ascomycota Members of the Division Ascomycota are known as the Sac Fungi and are fungi that produce spores in a distinctive type of microscopic sporangium called an ascus (Greek for a bag or wineskin). This monophyletic grouping... Species - Bush Chinkapin* - Japanese Chestnut - American Chestnut - Henrys Chestnut - Chinese Chestnut - Ozark Chinkapin - Alleghany Chinkapin - Sweet Chestnut - Seguins Chestnut * treated as a synonym of by many authors Chestnuts (Castanea), including the chinkapins, are a genus of eight or nine species of trees and shrubs in the beech family... Binomial name Castanea dentata (Marsh. ...

The blight appears to have been introduced from either China or Japan. Japanese and some Chinese chestnut trees are resistant to the fungus: they may be infected, but the blight does not usually kill them. Blight is the name for any of a number of diseases affecting many species of plants. ...

Despite the devastation the blight caused to the American Chestnut tree, the root collar and root system of the tree are fairly resistant to the blight, so a large number of small American Chestnut trees still exist as shoots from existing root bases. However, the shoots are seldom able to grow enough to reproduce before the blight attacks them.

Cankers caused by the fungal infection cause the tree trunk to split.

The fungus is spread by an unknown agent, but it is local in range, so many American Chestnuts survive where there is no other tree within 10 km. Also, there are at least two pathogens which weaken the fungus (hypovirulence) and many trees survive that way. Surviving chestnut trees are being bred for resistance to the blight. Image File history File links Chestnut_blight. ... Image File history File links Chestnut_blight. ...

External link

• American Chestnut Cooperators' Foundation - Blight Fungus