Any of several perennial water plants of the genus Trapa (family Trapaceae), native to Europe, Asia, and Africa, or their edible, nutlike fruit. The water caltrop (T. natans) has two sets of leaves—long, feathery, rootlike, submerged leaves and a loose rosette of floating leaves attached to leafstalks 2–4 in (5–10 cm) long. The small fruit usually has four spiny angles. The Chinese water chestnut (Eleocharis tuberosus or E. dulcis) is a member of the sedge family.
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Family Hippocastanaceae, composed of the buckeyes and the horse chestnuts (genus Aesculus), native to the northern temperate zone. The best-known species of horse chestnut is the common, or European, horse chestnut (A. hippocastanum), native to southeastern Europe but widely cultivated as a large shade and street tree. The Champs-Élysées in Paris is lined with rows of horse-chestnut trees.
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Plant disease caused by the fungus Endothia parasitica. Accidentally imported from East Asia and first observed in 1904 in New York, it has killed almost all native American chestnuts (Castanea dentata) in the U.S. and Canada and is destructive in other countries. Other blight-susceptible species include the European chestnut (C. sativa), the post oak (Quercus stellata), and the live oak. Symptoms include reddish brown bark patches that develop into sunken or swollen and cracked cankers that kill twigs and limbs. Leaves on such branches turn brown and wither but remain attached for months. Gradually the entire tree dies. The fungus persists for years in short-lived sprouts from old chestnut roots and in less susceptible hosts. It is spread locally by splashing rain, wind, and insects, and over long distances by birds. Chinese (C. mollissima) and Japanese (C. crenata) chestnuts are resistant.
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Any of four species of deciduous ornamental and timber trees of the genus Castanea, in the beech family. Native to temperate regions of the Northern Hemisphere, they bear burrlike fruits that contain two or three edible nuts. The usually tall trees have furrowed bark and lance-shaped leaves. The American chestnut (C. dentata), which once extended over a large area of eastern North America, has been almost eliminated by chestnut blight. The other three species are the European chestnut (C. sativa), the Chinese chestnut (C. mollissima), and the Japanese chestnut (C. crenata). The nuts of these three have local importance as food and are exported in large quantities, and varieties of all three are cultivated as ornamentals. The European chestnut produces useful timber as well; the American chestnut also was an important source of lumber and nuts before the arrival of the blight.
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Chestnuts should not be confused with either Horse Chestnuts (genus Aesculus), or Water Chestnut (family Cyperaceae); these are unrelated to Castanea and are named for producing respectively nuts of similar appearance but of no notable edibility, and tubers of similar taste from an aquatic herbaceous plant. Other trees commonly mistaken for the Chestnut tree are the Chestnut Oak (Fagaceae Quercus prinus) and the American Beech (Fagus grandifolia).
The following synonyms are or have been in use: Fagus castanea (used by Linnaeus in first edition of Species Plantarum, 1753). Sardian nut. Jupiter's nut. Husked nut. Spanish Chestnut (U.S.).
The Chinese and more so the Japanese Chestnuts are both often multi-leadered and wide-spreading, whereas European and especially American species tend to grow very erect when planted among others, with little tapering of their columnar trunk which is firmly set and massive. When standing on their own they spread on the sides and develop broad, rounded, dense crowns at maturity. The two latter's foliage has striking yellow Autumn colouring.
Its bark is smooth when young, of a vinous maroon or red-brown colour for the American Chestnut,, grey for the European Chestnut. With age American species' becomes grey and darker, thick and deeply furrowed; the furrows run longitudinally, and tend to twist around the trunk as the tree ages – it sometimes reminds of a large cable with twisted strands.
The leaves are simple, ovate or lanceolate, 10-30 cm long and 4-10 cm broad, with sharply pointed, widely-spaced teeth, with shallow rounded sinuates between.
The flowers follow the leaves, appearing in late Spring or early Summer or onto July. They are arranged in long catkins of two kinds, with both kinds being borne on every tree. Some catkins are made of only male flowers, which mature first. Each flower has eight stamens, or 10 to 12 for Castanea mollissima. The ripe pollen carries a heavy sweet odour that some people find too sweet or unpleasant. Other catkins have these pollen-bearing flowers but also carry near the twig from which these spring, small clusters of female or fruit-producing flowers. Two or three flowers together form a four-lobed prickly calybium which ultimately grows completely together to make the brown hull, or husk, covering the fruits.
The fruit is contained in a spiny (very sharp) cupule 2 to 3 inches or 5 to 11 centimetres diameter, also called "bur" or "burr". The burrs are often paired or clustered on the branch and contain one to seven nuts according to the different species, varieties and cultivars. At around the time when the fruits reach maturity, the burrs turn yellow-brown and split open in 2 or 4 sections. They can remain on the tree longer than they hold the fruit, but more often achieve complete opening and release the fruits only after having fallen on the ground and partly due to soil humidity.
The Chestnut fruit has a pointy end with at the tip a small tuft called 'flame' in Italian, and a hilum – an oblong spot at the other end of the fruit. In many varieties the fruit is flattened on one or two sides. It has two skins. The first one, is a hard outer shiny brown hull or husk, called the pericarpus; the industry calls it 'the peel'. Underneath the pericarpus is another thinner skin, also called "pellicle" or "episperm". The pellicle closely adheres to the seed itself, following the grooves usually present at the surface of the fruit. These grooves are of variable sizes and depth according to the species and varieties. They make the peeling in most cases difficult without the appropriate technique – (external link)
The fruit inside these shows two cotyledons with a creamy-white flesh throughout, except in some varieties which show only one cotyledons, and whose episperm is only slightly if not intruded at all. Usually these varieties have only one large fruit per burr, well rounded (no flat face) and which is called "marron" ("Marron de Lyon" in France, "Marron di Mugello" in Italy, "Paragon", ...).
The superior fruiting varieties among European Chestnuts have good size, sweet taste and easy-to-remove inner skins. American Chestnuts are usually very small (around 5 g), but sweet tasting with easy-to-remove pellicles. Some Japanese varieties have huge nuts (around 40 g), with typically difficult to remove pellicles. Chinese Chestnuts' pellicle is usually easy to remove and their sizes vary greatly according to the varieties, although usually smaller than the Japanese Chestnut.
for millennia, largely replacing cereals where these would not grow well, if at all, in mountainous Mediterranean areas. Alexander the Great and the Romans planted Chestnut trees across Europe while on their various campaigns. The Greek army is said to have survived their retreat from Asia Minor in 401-399 B.C. thanks to their stores of chestnuts. Ancient Greeks like Dioscorides and Romans such as Galen, wrote of chestnuts to comment on their medicinal properties – and of the flatulence induced by eating too much of it. To the early Christians chestnuts symbolized chastity. Until the introduction of the potato, whole forest-dwelling communities which had scarce access to wheat flour relied on chestnuts as their main source of carbohydrates. In some parts of Italy a cake made of chestnuts is used as a substitute for potatoes.
In 1583 Charles Estienne and Jean Liébault write that "an infinity of people live on nothing else but (the chestnut)".. In 1802 an Italian agronomist said of Tuscany that "the fruit of the chestnut tree is practically the sole subsistence of our highlanders", while in 1879 it is said that it almost exclusively feeds whole populations for half the year, as "a temporary but complete substitution for cereals".
Boundary records compiled in the reign of John already showed the famous Tortworth Chestnut in South Gloucestershire, as a landmark; and it was also known by the same name of “Great Chestnut of Tortworth” in the days of Stephen. This tree measured over 50 feet in circumference at 5 feet from the ground in 1720. The Chestnut forests on Mount Etna contain many trees that are said to be even larger. Chestnut trees particularly flourish in the Mediterranean basin. In 1584 the Governor of Genua, who dominated Corsica, ordered to all farmers and landowners to plant four trees yearly, among which a Chestnut tree – plus Olive-, Fig- and Mulberry-trees (this assumedly lasted until the end of Genoese rule over Corsica in 1729). Many communities owe their origin and former richness to the ensuing Chestnut woods. In France the marron glacé, a candied chestnut involving 16 different processes in a typically French cooking style, is always served at Christmas and New Year's time. In Italy they are still given to the poor as a symbol of sustenance on St. Martin's Day, November 11 (in Modena at this occasion the chestnuts are soaked in wine before roasting and serving) and are also traditionally eaten on Saint Simon's Day in Tuscany.
Their popularity has declined during the last few centuries, partly due to their reputation of "food for poor people". Many people did not want to take chestnut bread as "bread" because chestnut flour does not rise. Some slandered chestnut products in such words as the bread which "gives a sallow complexion" written in 1770, or in 1841 "this kind of mortar which is called a soup" The last decades' worldwide renewal may have profited from the huge reforestation efforts started in the 30's in the United States, to establish a variety / varieties of Castanea sativa which may be resistant to chestnut-blight, as well as the strain on cereal supplies.
The main region in Italy for chestnut production is the Mugello region; in 1996 the European Community granted the IGP (Protected Geographic Indication; equivalent to the French Appellation d'Origine Contrôlée) status to the Mugello Sweet Chestnut It is markedly sweet, peels easily, is not excessively floury or astringent, and has notes of vanilla, hazelnut and more subtly of fresh bread. There is no "unpleasant" aroma such as yeast, fungus, mold or paper, which sometimes occur with other chestnuts. The main regions in France for chestnut production are the départements of Ardèche with the famous “Châtaigne d’Ardèche” (A.O.C), of the Var, and of the Lyon region. France annually produces over 1,000 tonnes but still imports about 8,000 tonnes, mainly from Italy.
In Portugal's archipelago of Madeira, Chestnut liquor is a traditional beverage, and it's gaining popularity with the tourists and in continental Portugal.
This was not long before America would measure the extent of the impending catastrophe. The discovery of the Chestnut blight fungus on some Asian Chestnut trees planted on Long Island, New York was made public in 1904. Within 40 years the near-4 billion-strong American Chestnut population in Northern America was devastated – only a few clumps of trees remained in California and the Pacific northwest. Due to disease, American Chestnut wood almost disappeared from the market for decades, although quantities of Chestnut wood can still be obtained as reclaimed lumber. Today they only survive as living stumps, or "stools", with only a few growing enough shoots to produce seeds shortly before dying. This is just enough to preserve the genetic material used to engineer an American Chestnut tree with the minimal necessary genetic input from any of the disease-immune Asiatic species. Efforts started in the 1930s are still ongoing to repopulate the country with these trees, in Massachusetts and many places elsewhere in the United States.
Today, the fruit's demand outstrips supply. The United States imported 4,056 metric tons of European in-shell chestnuts worth $10 million in 2007. But the U.S. chestnut industry is as yet in its infancy, producing less than 1 percent of total world production. Since the mid-twentieth century, most of the United States's imports are from Southern Italy with the large, meaty, and richly flavored Sicilian chestnut being considered among the best qualities for bulk sale and supermarket retail. But some imports come from Portugal and France. The next two largest sources of imports to the United States are China and South Korea. The French varieties of marrons are highly favoured and sold at high prices in gourmet shops.
Meanwhile, a 2005 study of the sector found that U.S.A. producers are mainly part-timers diversifying an existing agricultural business, or hobbyists. Another recent study indicates that investment in a new plantation takes 13 years to break even, at least within the current Australian market. But starting a small-scale operation demands only a relatively low initial investment, This is a factor in the small size of the present production operations, with half of them being within 3 to 10 acres. Another pre-determining factor in the small productivity of the sector, is that most orchards have been created less than 10 years ago so have young trees which are as now barely entering commercial production. Assuming a 10 kgs yield for a 10 year-old tree is a reliable conservative estimate, even though some exceptional specimens of that age have yielded 100kgs. So most producers earn less than $5,000 per year, with a third of the total not having sold anything so far.
Moreover, the plantings have so far been mostly of Chinese species, but the products are not readily available. The American Chestnut Foundation recommends holding on a little while more before large-scale planting. This is because it and its associates (the American Chestnut Cooperators' Foundation and many others from education, research and industry sectors contributing to the program) are at the last stages of developing a variety that is as close as possible to the lost American chestnut, while having incorporated the blight-resistant gene of the Asiatic species. Considering the added-value bonus that Chestnut trees can be easily grown organically, and assuming the development of brands in the market, there is little doubt that everything else being equal, home-grown products would reach higher prices than imports – the high volume of which indicates a market with expanding prospects. As of 2008, the price for chestnuts sold fresh in the shell ranges from $1.50 per pound wholesale to about $5 per pound retail, depending mainly on the size.
Their carbohydrates content compares with that of wheat and rice; it has twice as much starch as that of the potato. In some areas Sweet Chestnut trees are called "the bread tree". When chestnuts are just starting to ripen, the fruit is mostly starch and is very firm under finger pressure from the high water content. As the chestnuts ripen, the starch is slowly converted into sugars; and moisture content also starts decreasing. Upon pressing the chestnut a slight 'give' can be felt: the hull is not so tense, there is space between it and the flesh of the fruit. The water is being replaced by sugars, which means better conservation.
They are the only "nuts" that carry vitamin C. One ounce of boiled or steamed chestnuts has 7 mg of vitamin C; dried chestnuts have more than double that amount with 16.6 mg. for one ounce, as much as the lemon. Fresh chestnuts have a very high water content: superior to 52%, and a high transpiration rate similar to that of potatoes and onions. They can lose even 1% of weight in one day at 20°C and 70% relative humidity.
Tannin is contained in the bark as well as in the wood, leaves and seed husks. The husks contain 10 - 13% tannin.
The fruit also contains many other micro-nutrients:
| Constituent | Quantities | Comparison with apple |
|---|---|---|
| Proteins | about 3 g/100g to 4 g/100g. | 0.2 g/100g. |
| Lipids | from less than 2 g/100g to 2.6 g/100g. No cholesterol | 0.1 g/100g. |
| Glucids – starch | 28 g/100g to 44 g/100g. They contain twice as much starch as the potato. | xx |
| Glucids – soluble sugars | 8.1 g/100g in soluble sugars, monosaccharides and disaccharides, mainly sucrose, glucose, fructose, and, in less amount, stachyose, and raffinose. 3.3 g/100g. | 1.0 g/100g. |
| Total carbohydrates | 32.1 g/100g. | 14.0 g/100g. |
| Ashes | 1 g/100g. | xx |
| Fibers | 20 g/100g ou 14.9 g/100g. | 0.1 g/100g. |
| Water | High water content: superior to 52%. | 84.8%. |
| Iron | 1mg/100g to 1.2mg/100g. 0.7 mg/100g. | 0.3 mg/100g. |
| Zinc | 0.4 mg/100g. | 88 mg/100g. |
| Copper | mentioned. | xx |
| Manganese | mentioned. | xx |
| Phosphorus | 85mg/100g to 89mg/100g. | xx |
| Potassium | 500 mg/100g. 468 mg/100g. | 110 mg/100g. |
| Magnesium | mentioned. | xx |
| Sulfur | mentioned. | xx |
| Sodium | mentioned. 1.1mg/100g. 0.8mg/100g. | 1.0 mg/100g. |
| Calcium | 38mg/100g to 40mg/100g. 17.6 mg/100g. | 7.0 mg/100g. |
| Vitamin B1 | mentioned. (anti-beriberic, or aneurin, or thiamine) 0.22mg/100g. | xx |
| Vitamin B2 | mentioned. (riboflavin) 0.35 mg/100g. | xx |
| Vitamin B3 | (nicotinic acid, niacin or orniacin) 1.4mg/100g. | xx |
| Vitamin C | 50mg/100g, as much as in the lemon. | xx |
It can be found at altitudes between 200 and 1000 metres above sea level; some mention between 300 and 750m altitude, while the famous Chestnut Tree of One Hundred Horses on Mount Etna stands at 4000 feet altitude.). It can tolerate maritime exposure although its growth is reduced.
When grown from seed, the trees do not begin to yield fruit until they are thirty to forty years-old. Grafted trees can start bearing in their fifth year.
The seed germinates in late winter or early spring. The seed's life length is short. If kept moist, it can be stored in a cool place for a few months, but must be checked regularly for signs of germination. Low temperature prolongs dormancy. It is better sown as soon as it is ripe: either in a cold frame or seed bed outdoors, where it can be left in situ for 1 to 2 years before being planted in their permanent positions; Or in pots, where the plants can be put out into their permanent positions in summer or autumn. They must be protected from the cold in their first winter, and also from mice and squirrels.
Chestnuts are considered self-sterile, so at least two trees are needed for pollination.
The other way of eating the fruit which does not involve peeling, is to roast them. Any method of cooking requires to score the fruit beforehand, else the flesh expands and the fruit explodes. Once cooked its texture is similar to a baked potato, with a delicate, sweet, nutty flavour.
Chestnuts can be dried and milled into flour, which can then be used to prepare breads, cakes, pancakes, pastas (it is the original ingredient for "polenta", known in Corsica as "pulenda"), used as thickener for stews, soups, sauces..., . The flour can be light beige like that from Castagniccia, or darker in other regions. It is a good solution for long storage of a nutritious food. Chestnut bread keeps fresh for as long as two weeks.
A fine granular sugar can be obtained from the fermentation of the juice, as well as a beer; and the roasted fruit provides a coffee substitute. Parmentier, the famous potato promoter among other achievements of his, extracted sugar from chestnuts and sent a chestnut sugarloaf of several pounds' weight to the Academy of Lyon. The continental blockade following shortly after (1806-1814) increased the research into developing chestnuts as a source of sugar, but Napoleon chose beets instead.
The nuts can also be eaten candied, boiled, steamed, grilled, roasted or fried (fritters), in sweet or savoury recipes. They can be used to stuff vegetables, poultry, fowl and other edibles. They are available fresh, dried, ground, canned (whole or in puree).
Candied chestnuts (whole chestnuts candied in sugar syrup, then iced) are sold under the French name marrons glacés or Turkish name kestane şekeri ("sugared chestnuts"). They appeared in France in the 16th century. Towards the end of 19th century, Lyon is brought low by the collapse of the textile market, notably silk. Clément Faugier ingénieur des Ponts et Chaussées, is looking for a way to revitalize the regional economy. In 1882 at Privas, he invented the technology to make marrons glacés on an industrial scale (although a great deal of the over-twenty necessary steps from harvest to the finished product are still accomplished manually). Chestnuts are picked in autumn, and candied from the start of the following summer for the ensuing Christmas. Thus the marrons glacés eaten at Christmas are those picked the year before.
Sweet Chestnuts are not easy to peel when cold. The most efficient way to peel them is described here
One kilogram of (untainted) chestnuts yields approximately 700g of shelled chestnuts.
Chestnuts' taste vary slightly from one to the next but is somewhat sweet and certainly unique. Chestnut-based recipes and preparations are making a comeback in Italian cuisine, as part of the trend toward rediscovery of traditional dishes and better nutrition.
The tannin in leaves and bark makes these astringent, useful to treat bleedings, diarrhoeas etc. They are anti-inflammatory, astringent, expectorant and tonic. The leaves are harvested in June or July and can be used fresh or dried. An infusion has been used in the treatment of fevers and ague, but are mainly employed for their efficacy in treating convulsive coughs such as whooping cough and other irritable conditions of the respiratory system. The leaves can also be used in the treatment of rheumatism, to ease lower back pains and to relieve stiff muscles and joints. A decoction is a useful gargle for treating sore throats. The bark has been used as antidiarrheic because of the tannins.
The plant is used in Bach flower remedies - the keywords for prescribing it are 'Extreme mental anguish', 'Hopelessness' and 'Despair'[209].
Wood extract (mixed at a 1:2 to 1:6 ratio with sugar) is used as a natural agent for the prevention and cure of diarrhoea in animals.
Chestnut is of the same family as Oak, and likewise its wood contains much tannins. This renders the wood very durable, gives it excellent natural outdoor resistance, and saves the need for other protection treatment. It also corrodes iron rapidly although copper, brass or stainless metals are not affected.
Chestnut timber is decorative: light brown in colour, it is sometimes confused with Oak wood. Both woods' textures are also similar. When in a growing stage thus with very little sap wood, a Chestnut tree contains more timber of a durable quality than an Oak of the same dimensions. Young Chestnut wood has proved more durable than Oak for woodwork that has to be partly in the ground, such as stakes and fences.
After most growth is achieved, Chestnut timber tends to split and warp more the older it is harvested; it becomes neither as hard nor quite as strong as Oak wood. The American Chestnut Castanea dentata served as an important source of lumber, because that species has long unbranched trunks. In England it was nevertheless formerly used indiscriminately with Oak for the construction of houses, mill-work and household furniture. It grows so freely in that country, that it was long considered a true native – partly because the roof of Westminster Hall and the Parliament House of Edinburgh were mistakenly thought of as Chestnut wood. But Chestnut wood loses much of its durability when grown beyond fifty years old, and despite the local Chestnut's quick growth rate it remains that the timber used for these two buildings is considerably larger than a 50-year-old Chestnut's girth. It has been now proved that they are of Durmast Oak, which grain and colour closely resembles that of Chestnut.
It is therefore uncommon to find large pieces of Chestnut wood in building structures, but it has nevertheless always been highly-valued for small outdoor furniture pieces where durability is important, such as fencing and wooden outdoor cladding ('shingles') for covering buildings., pit-props In Italy, it is also used to make barrels used for aging balsamic vinegar. Of note the famous eighteenth century's "berles" in the French Cévennes: cupboards cut directly from the hollowed trunk.
Fabric can be starched with chestnut meal
Linen cloth can be whitened with chestnut meal
The leaves and the skins (husk and pellicle) of the fruits provide a hair shampoo.