American chestnut

Castanea dentata

The American chestnut is a large, monoecious deciduous tree of the beech family native to eastern North America. Before the species was devastated by the chestnut blight, a fungal disease, it was one of the most important forest trees throughout its range, and was considered the finest chestnut tree in the world. It is estimated that between 3 and 4 billion American chestnut trees were destroyed in the first half of the 20th century by blight after its initial discovery in 1904. Very few mature specimens of the tree exist within its historical range, although many small shoots of the former live trees remain. There are hundreds of large American chestnuts outside its historical range, some in areas where less virulent strains of the pathogen are more common, such as the 600 to 800 large trees in northern Lower Michigan.
American Chestnut (Castanea dentata) In a conservation area at Berry College in Mt. Berry, Georgia. I was limited in getting any shots as there was a locked gate/fence to this area!! Maybe next time!

Over 100 years ago, there were over 4 billion American Chestnut trees growing in the eastern United States. Not only was it used as lumber, but its nuts were a rich food source for many animals. 

Unfortunately, ecological disaster struck when Cryphonectria parasitica, an ascomycete fungus, was introduced to the American Chestnut. Thought to have been introduced from Asian trees (in an attempt to produce larger nuts), C. parasitica reduced the dominant tree species in eastern North america to near extinction in a matter of 40 years. As its Latin name implies, C. parasitica parasitizes trees. The American Chestnut is particularly susceptible to this fungus and is quickly invaded via cracks/wounds in its bark. The fungus can further grow through the cambium, eventually girdling (cutting off nutrient supply) and killing the tree. 

https://www.jungledragon.com/image/64964/american_chestnut_castanea_dentata.html American chestnut,Castanea dentata,Geotagged,Summer,United States

Appearance

''Castanea dentata'' is a rapidly growing deciduous hardwood tree, historically reaching up to 30 metres in height, and 3 metres in diameter. It ranged from Maine and southern Ontario to Mississippi, and from the Atlantic coast to the Appalachian Mountains and the Ohio Valley. ''C. dentata'' was once one of the most common trees in the Northeastern United States. In Pennsylvania alone, it is estimated to have comprised 25–30% of all hardwoods. The tree's huge population was due to a combination of rapid growth and a large annual seed crop in comparison to oaks which do not reliably produce sizable numbers of acorns every year. Nut production begins when ''C. dentata'' is 7–8 years old.

There are several similar chestnut species, such as the European sweet chestnut, Chinese chestnut, and Japanese chestnut. The American species can be distinguished by a few morphological traits, such as leaf shape, petiole length and nut size. For example, it has larger and more widely spaced saw-teeth on the edges of its leaves, as indicated by the scientific name ''dentata'', Latin for "toothed".

The leaves, which are 14–20 cm long and 7–10 cm broad, also tend to average slightly shorter and broader than those of the sweet chestnut. The blight-resistant Chinese chestnut is now the most commonly planted chestnut species in the US, while the European chestnut is the source of commercial nuts in recent decades. It can be distinguished from the American chestnut by its hairy twig tips which are in contrast to the hairless twigs of the American chestnut. The chestnuts are in the beech family along with beech and oak, but are not closely related to the horse-chestnut, which is in the family Sapindaceae.

The chestnut is monoecious, producing many small, pale green male flowers found tightly occurring along 6 to 8 inch long catkins. The female parts are found near base of the catkins and appear in late spring to early summer. Like all members of the Fagaceae family, American chestnut is self-incompatible and requires two trees for pollination, which can be any member of the Castanea genus.

The American chestnut is a prolific bearer of nuts, usually with three nuts enclosed in each spiny, green burr, and lined in tan velvet. The nuts develop through late summer, with the burrs opening and falling to the ground near the first fall frost.

The American chestnut was a very important tree for wildlife, providing much of the fall mast for species such as white-tailed deer and wild turkey and, formerly, the passenger pigeon. Black bears were also known to eat the nuts to fatten up for the winter. The American chestnut also contains more nitrogen, phosphorus, potassium and magnesium in its leaves when compared to other trees that share its habitat. This means they return more nutrients to the soil which helps with the growth of other plants, animals, and microorganisms.
Castanea_dentata  American chestnutCastanea dentata,Castanea dentata,Geotagged,Summer,United States

Distribution

The total number of chestnut trees in eastern North America was estimated at over three billion, and 25% of the trees in the Appalachian Mountains were American chestnut. The number of large surviving trees over 60 cm in diameter within its former range is probably fewer than 100. American chestnuts were also common part of the forest canopy in southeast Michigan.

Although large trees are currently rare east of the Mississippi River, it exists in pockets in the blight-free West, where the habitat was agreeable for planting: settlers took seeds for American chestnut with them in the 19th century. Huge planted chestnut trees can be found in Sherwood, Oregon, as the Mediterranean climate of the West Coast discourages the fungus, which relies on hot, humid summer weather. American chestnut also thrives as far north as Revelstoke, British Columbia.

At present, it is believed that survival of ''C. dentata'' for more than a decade in its native range is almost impossible. The fungus uses various oak trees as a host, and while the oak itself is unaffected, American chestnuts nearby will succumb to the blight in approximately a year or more. In addition, the hundreds of chestnut stumps and "living stools" dotting eastern woodlands may still contain active pathogens.
American Chestnut (Castanea dentata) In a conservation area at Berry College in Mt. Berry, Georgia. I was limited in getting any shots as there was a locked gate/fence to this area!! Maybe next time!

Over 100 years ago, there were over 4 billion American Chestnut trees growing in the eastern United States. Not only was it used as lumber, but its nuts were a rich food source for many animals. 

Unfortunately, ecological disaster struck when Cryphonectria parasitica, an ascomycete fungus, was introduced to the American Chestnut. Thought to have been introduced from Asian trees (in an attempt to produce larger nuts), C. parasitica reduced the dominant tree species in eastern North america to near extinction in a matter of 40 years. As its Latin name implies, C. parasitica parasitizes trees. The American Chestnut is particularly susceptible to this fungus and is quickly invaded via cracks/wounds in its bark. The fungus can further grow through the cambium, eventually girdling (cutting off nutrient supply) and killing the tree.  

https://www.jungledragon.com/image/64965/american_chestnut_castanea_dentata.html American chestnut,Castanea dentata,Geotagged,Summer,United States

Food

The nuts were once an important economic resource in North America, being sold on the streets of towns and cities, as they sometimes still are during the Christmas season . Chestnuts are edible raw or roasted, though typically preferred roasted. Nuts of the European sweet chestnut are now sold instead in many stores. One must peel the brown skin to access the yellowish-white edible portion. The unrelated horse-chestnut's seeds are poisonous without extensive preparation. Native Americans used various parts of the American chestnut to treat ailments such as whooping cough, heart conditions and chafed skin.

References:

Some text fragments are auto parsed from Wikipedia.

Status: Not evaluated
EX EW CR EN VU NT LC
Taxonomy
KingdomPlantae
DivisionAngiosperms
ClassEudicots
OrderFagales
FamilyFagaceae
GenusCastanea
SpeciesC. dentata