An oak is a hardwood tree or shrub in the genus Quercus of the beech family. They have spirally arranged leaves, often with lobed edges, and a nut called an acorn, borne within a cup. The genus is widely distributed in the Northern Hemisphere; it includes some 500 species, both deciduous and evergreen. Fossil oaks date back to the Middle Eocene. Molecular phylogeny shows that the genus is divided into Old World and New World clades, but many oak species hybridise freely, making the genus's history difficult to resolve.
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.
Beech (Fagus) is a genus of deciduous trees in the family Fagaceae, native to temperate Eurasia and North America. There are 13 accepted species in two distinct subgenera, Engleriana and Fagus. The subgenus Engleriana is found only in East Asia, distinctive for its low branches, often made up of several major trunks with yellowish bark. The better known Fagus subgenus beeches are native to Europe and North America. They are high-branching trees with tall, stout trunks and smooth silver-grey bark. The European beech Fagus sylvatica is the most commonly cultivated species, yielding a utility timber used for furniture construction, flooring and engineering purposes, in plywood, and household items. The timber can be used to build homes. Beechwood makes excellent firewood. Slats of washed beech wood are spread around the bottom of fermentation tanks for Budweiser beer. Beech logs are burned to dry the malt used in some German smoked beers. Beech is also used to smoke Westphalian ham, andouille sausage, and some cheeses.
Fraxinus excelsior, known as the ash, or European ash or common ash to distinguish it from other types of ash, is a flowering plant species in the olive family Oleaceae. It is native throughout mainland Europe east to the Caucasus and Alborz mountains, and Great Britain and Ireland, the latter determining its western boundary. The northernmost location is in the Trondheimsfjord region of Norway. The species is widely cultivated and reportedly naturalised in New Zealand and in scattered locales in the United States and Canada.
Platanus occidentalis, also known as American sycamore, American planetree, western plane, occidental plane, buttonwood, and water beech, is a species of Platanus native to the eastern and central United States, the mountains of northeastern Mexico, extreme southern Ontario, and extreme southern Quebec. It is usually called sycamore in North America, a name which can refer to other types of trees in other parts of the world. The American sycamore is a long-lived species, typically surviving at least 200 years and likely as long as 500–600 years.
Fagus sylvatica, the European beech or common beech is a large, graceful deciduous tree in the beech family with smooth silvery-gray bark, large leaf area, and a short trunk with low branches.
Fagus grandifolia, the American beech or North American beech, is the only species of beech native to North America. Its current range comprises the eastern United States, isolated pockets of Mexico and southeastern Canada. Prior to the glacial maximum of the Pleistocene epoch, the tree flourished over most of North America, reaching California.
The mountain pine beetle is a species of bark beetle native to the forests of western North America from Mexico to central British Columbia. It has a hard black exoskeleton, and measures approximately 5 millimetres, about the size of a grain of rice.
Nothofagus cunninghamii, commonly known as myrtle beech or Tasmanian myrtle, is the dominant species of cool temperate rainforests in Tasmania and Southern Victoria. It has low fire resistance and grows best in partial shade conditions.
Beech bark disease is a disease that causes mortality and defects in beech trees in the eastern United States, Canada and Europe. In North America, the disease occurs after extensive bark invasion by Xylococculus betulae and the beech scale insect, Cryptococcus fagisuga. Through a presently unknown mechanism, excessive feeding by this insect causes two different fungi to produce annual cankers on the bark of the tree. The continuous formation of lesions around the tree eventually girdles it, resulting in canopy death. In Europe, N. coccinea is the primary fungus causing the infection. Infection in European trees occurs in the same manner as it does in North American trees. Though the disease still appears in Europe, it is less serious today than it once was.
Nothofagus truncata, or hard beech, is a species of tree endemic to New Zealand. Its common name derives from the fact that the timber has a high silica content, making it tough and difficult to saw. Hard beech is a tree up to 30m tall occurring in lowland and lower montane forest from latitude 35°S to 42°30'S, that is, from the north of the North Island southwards to Marlborough and south Westland in the South Island. In Taranaki it forms almost pure stands on the rugged sandstone country there and is partially deciduous, dropping many of its leaves at the end of the winter. N. truncata became known as Fuscospora truncata after 2013 in New Zealand.
Neonectria ditissima is a fungal plant pathogen. It causes cankers that can kill branches of trees by choking them off. Apple and beech trees are two susceptible species.
Nectria coccinea is a fungal plant pathogen. The variant Nectria coccinea var. faginata causes beech bark disease, and can infect the tree via the feeding holes made by the beech scale insect Cryptococcus fagisuga.
Forest dieback is a condition in trees or woody plants in which peripheral parts are killed, either by pathogens, parasites or conditions like acid rain, drought, and more. These episodes can have disastrous consequences such as reduced resiliency of the ecosystem, disappearing important symbiotic relationships and thresholds. Some tipping points for major climate change forecast in the next century are directly related to forest diebacks.
Cydia pactolana, the spruce bark tortrix, is a moth of the family Tortricidae. It is found in central, northern and eastern Europe as well as Siberia. In Japan, the subspecies Cydia pactolana yasudai is present.
Cryptococcus fagisuga, commonly known as the beech scale or woolly beech scale, is a felted scale insect in the superfamily Coccoidea that infests beech trees of the genus Fagus. It is associated with the transmission of beech bark disease because the puncture holes it makes in the bark allow entry of pathogenic fungi which have been identified as Nectria coccinea var. faginata and sometimes Nectria galligena.
Eriococcidae is a family of scale insects in the order Hemiptera. They are commonly known as felt scales or eriococcids. As of 2023, there are 109 genera and 681 species. Each species is usually specific to a different plant host, or closely related group of hosts.
Neonectria is a genus of fungi in the family Nectriaceae.
Beech leaf disease is a newly discovered lethal disease of beech trees believed to be caused by the nematode Litylenchus crenatae mccannii. The symptoms of the disease appear as a dark green, interveinal banding pattern on the lower canopy foliage, eventually spreading throughout the tree. The symptoms appear to progress through the buds and no new leaves are produced. This eventually results in the death of the tree. The disease has the potential to drastically alter the Eastern deciduous forests of the United States on its own and through potential compounding disease effects.
