From Wikipedia, the free encyclopedia - View original article
|Sweet chestnut Castanea sativa|
Castanea alnifolia - bush chinkapin*
|Sweet chestnut Castanea sativa|
Castanea alnifolia - bush chinkapin*
The chestnut group, some species called chinkapin or chinquapin, is a genus (Castanea) of eight or 9 species of deciduous trees and shrubs in the beech family Fagaceae, native to temperate regions of the Northern Hemisphere. The name also refers to the edible nuts they produce.
Chestnuts should not be confused with horse chestnuts (genus Aesculus), which are not related to Castanea and are named for producing nuts of similar appearance, but which are mildly poinonous to humans, nor should they be confused with water chestnut (family Cyperaceae), which are also unrelated to Castanea and are tubers of similar taste from an aquatic herbaceous plant. Other trees commonly mistaken for the chestnut tree are the chestnut oak (Quercus prinus) and the American beech (Fagus grandifolia).
The name Castanea is probably derived from the old name for the sweet chestnut, either in Latin or in Ancient Greek. Another possible source of the name is the town of Kastania in Thessaly, Greece; more probablt, though, the town took its name from the most common tree growing around it. In the Mediterranean climate zone, chestnut trees are rarer in Greece because the chalky soil is not conducive to the tree's growth. Kastania is located on one of the relatively few sedimentary or siliceous outcrops. They grow so abundantly there, their presence would have determined the place's name. Still others take the name as coming from the Greek name of Sardis glans (Sardis acorn) – Sardis being the capital of Lydia, Asia Minor, from where the fruit had spread.
The trees' names are virtually identical in all the most ancient languages of Central Europe: in Breton kistinen for the tree, and kistin for its fruit, in Welsh castan-wydden and sataen, in Dutch kastanje for both the tree and its fruit, in Albanian gështenjë, and many others close to the French châtaigne and to the Latin name chosen for the genus.
The name is cited twice in the King James Version of the Bible. In one instance, Jacob puts peeled twigs in the water troughs to promote healthy offspring of his livestock. Although it may indicate another tree, it indicates the fruit was a local staple food at that time.
Chestnut trees are of moderate growth rate (for the Chinese chestnut tree) to fast-growing for American and European species. Their mature heights vary from the smallest species of chinkapins, often shrubby, to the giant of past American forests, Castanea dentata that could reach 60 m. In between these extremes are found the Japanese chestnut (Castanea crenata) at 10 m average;[Note 1] followed by the Chinese chestnut (Castanea mollissima) at about 15 m, then the European chestnut (Castanea sativa) around 30 m.
The Chinese and more so the Japanese chestnuts are both often multileadered and wide-spreading, whereas European and especially American species tend to grow very erect when planted among others, with little tapering of their columnar trunks, which are 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' bark 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 one of a large cable with twisted strands.
The flowers follow the leaves, appearing in late spring or early summer or into 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 5–11 cm in 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. Around the time the fruits reach maturity, the burrs turn yellow-brown and split open in two or four 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; opening is partly due to soil humidity.
The chestnut fruit has a pointed end with a small tuft at its tip (called "flame" in Italian), and at the other end, a hilum – a pale brown attachment scar. In many varieties, the fruit is flattened on one or two sides. It has two skins. The first one is a hard, shiny, brown outer hull or husk, called the pericarpus; the industry calls this the "peel". Underneath the pericarpus is another, thinner skin, called the 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 depths according to the species and variety.
The fruit inside these shows two cotyledons with a creamy-white flesh throughout, except in some varieties which show only one cotyledon, and whose episperm is only slightly or 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, or "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 very large nuts (around 40 g), with typically difficult-to-remove pellicles. Chinese chestnut pellicles are usually easy to remove, and their sizes vary greatly according to the varieties, although usually smaller than the Japanese chestnut.
The sweet chestnut was introduced into Europe from Sardis, in Asia Minor; the fruit was then called the 'Sardian nut'. It has been a staple food in southern Europe, Turkey and southwestern and eastern Asia for millennia, largely replacing cereals where these would not grow well, if at all, in mountainous Mediterranean areas. Evidence of its cultivation by man is found since around 2000 B.C. Alexander the Great and the Romans planted chestnut trees across Europe while on their various campaigns. A Greek army is said to have survived their retreat from Asia Minor in 401-399 BC thanks to their stores of chestnuts. Ancient Greeks like Dioscorides and 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 wrote 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 was said that it almost exclusively fed 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 (15 m) in circumference at 5 feet (1.5 m) 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 Modena, Italy, they are soaked in wine before roasting and serving,) and are also traditionally eaten on Saint Simon's Day in Tuscany. It is traditional to eat roasted chestnuts in Portugal on St. Martin's Day.
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 1930s in the United States to establish varieties of Castanea sativa which may be resistant to chestnut blight, as well as to relieve the strain on cereal supplies.
The main region in Italy for chestnut production is the Mugello region; in 1996 the European Community granted the fruit 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, 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 metric tons, but still imports about 8,000 metric tons, mainly from Italy.
In Portugal's archipelago of Madeira, chestnut liquor is a traditional beverage, and it is gaining popularity with the tourists and in continental Portugal.
Always served as part of the New Year menu in Japan, chestnuts represent both success and hard times— mastery and strength. The Japanese chestnut (called kuri) was in cultivation before rice and the Chinese chestnut (Castanea mollissima) possibly for 2,000 to 6,000 years.
During British colonial rule in the mid-1700s to 1947, the Sweet Chestnut (Castanea sativa) was widely introduced in the temperate parts of the Indian Subcontinent, mainly in the lower-to-middle Himalayas. They are widely found in British-founded hill stations in Northern India, and to a lesser extent in Bhutan and Nepal. They are mainly used as an ornamental tree and are found in almost all British-founded botanical gardens and official governmental compounds (such as larger official residences) in temperate parts of the Indian Subcontinent.
Aboriginal Americans were eating the American chestnut species, mainly Castanea dentata and some others, long before European immigrants introduced their stock to America, and before the arrival of chestnut blight. In some places, such as the Appalachian Mountains and others, one quarter of hardwoods were chestnuts. Mature trees often grew straight and branch-free for 50 feet (15 m), up to 100 feet, averaging up to 5 feet in diameter. For three centuries, most barns and homes east of the Mississippi River were made from it. In 1911, the famous food book The Grocer's Encyclopedia noted that a cannery in Holland included in its "vegetables-and-meat" ready-cooked combinations, a "chestnuts and sausages" casserole besides the more classic "beef and onions" and "green peas and veal". This to celebrate the chestnut culture that would bring whole villages out in the woods for three weeks each autumn (and keep them busy all winter), and to deplore the lack of food diversity in the United States's shop shelves.
But soon after that, the American chestnuts were nearly wiped out by chestnut blight. The discovery of the blight fungus on some Asian chestnut trees planted on Long Island, New York was made public in 1904. Within 40 years, the near-four billion-strong American chestnut population in North America was devastated; only a few clumps of trees remained in Michigan, Wisconsin, California and the Pacific Northwest. Due to disease, American chestnut wood almost disappeared from the market for decades, although quantities can still be obtained as reclaimed lumber. Today, they only survive as single trees separated from any others (very rare), and 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 nut's demand outstrips supply. The United States imported 4,056 metric tons of European in-shell chestnuts worth $10 million in 2007. The U.S. chestnut industry is in its infancy, producing less than 1% of total world production. Since the mid-20th century, most of the US imports are from Southern Italy, with the large, meaty, and richly flavored Sicilian chestnuts being considered among the best quality for bulk sale and supermarket retail. Some imports come from Portugal and France. The next two largest sources of imports are China and South Korea. The French varieties of marrons are highly favoured and sold at high prices in gourmet shops.
A study of the sector in 2005 found that US 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. Starting a small-scale operation requires 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 (40,000 m2). Another predetermining 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 kilograms (22 lb) yield for a 10 year-old tree is a reliable conservative estimate, though some exceptional specimens of that age have yielded 100 kilograms (220 lb). 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 waiting 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 additional advantage that chestnut trees can be easily grown organically, and assuming the development of brands in the market, it has been asserted 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 ($3.30/kg) wholesale to about $5 per pound ($11/kg) retail, depending mainly on the size.
The Australian gold rush of the 1850s and 1860s saw the first recorded plantings of European chestnut trees, brought in from Europe by the first settlers. Along the years, most but not all chestnut tree plantations were Castanea sativa stock, which is still the dominant species. Some of these are still standing today. Some trees in northern Victoria are around 120 years old and up to 60 metres tall.
Chestnuts grow well in southwest Western Australia, which has cold winters and warm to hot summers. As of 2008, the country has just under 350 growers, annually producing around 1,200 metric tons of chestnuts, of which 80% comes from northeast Victoria. The produce is mostly sold to the domestic fresh fruit market. Chestnuts are now slowly gaining popularity in Australia. A considerable increase in production is expected in the next 10 years, due to the increase in commercial plantings during the last fifteen to twenty-five years. By far the most common species in Australia is the European chestnut, but there are small numbers of the other species, as well as some hybrids.
The Japanese chestnut (Castanea crenata) does well in wet and humid weather and in hot summers (~30 °C); and was introduced to New Zealand in the early 1900s, more so in the upper North Island region
|Nutritional value per 100 g (3.5 oz)|
|Energy||820 kJ (200 kcal)|
|- Sugars||11 g|
|Vitamin A equiv.||1 μg (0%)|
|Thiamine (vit. B1)||0.144 mg (13%)|
|Riboflavin (vit. B2)||0.016 mg (1%)|
|Niacin (vit. B3)||1.102 mg (7%)|
|Vitamin B6||0.352 mg (27%)|
|Folate (vit. B9)||58 μg (15%)|
|Vitamin B12||0 μg (0%)|
|Vitamin C||40.2 mg (48%)|
|Calcium||19 mg (2%)|
|Iron||0.94 mg (7%)|
|Magnesium||30 mg (8%)|
|Phosphorus||38 mg (5%)|
|Potassium||484 mg (10%)|
|Sodium||2 mg (0%)|
|Zinc||0.49 mg (5%)|
|Percentages are relative to|
US recommendations for adults.
Source: USDA Nutrient Database
Fresh chestnut fruits have about 180 calories (800 kJ) per 100 grams of edible parts, which is much lower than walnuts, almonds, other nuts and dried fruit (about 600 kcal/100 g). Chestnuts contain no cholesterol and contain very little fat, mostly unsaturated, and no gluten.
Their carbohydrate content compares with that of wheat and rice; chestnuts have twice as much starch as the potato. In addition, chestnuts contain about 8 percent of various sugars, mainly sucrose, glucose, fructose, and, in less amount, stachyose, and raffinose. 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, and 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 contain vitamin C, with about 40 mg per 100 g of raw product, which is about 65 percent of the U.S. recommended daily intake. The amount of vitamin C decreases by about 40 percent after heating. Fresh chestnuts contain about 52 percent water by weight, which will evaporate relatively quickly during storage; they can lose even 1 percent of weight in one day at 20°C (68°F) and 70% relative humidity.
Chestnuts produce a better crop when subjected to chill temperatures during the dormant period. Frosts and snowfalls are beneficial rather than harmful to the trees. The dormant plant is very cold-hardy in Britain. Chestnut is hardy to zone 5, which is 22 °C (12 °F) lower in average minimal temperature than London in zone 9. But the young growth in spring, even on mature plants, is frost-tender; bud-burst is later than most other fruit trees, so late frosts can be damaging to young buds.
Trees can be found at altitudes between 200 and 1000 metres above sea level; some mention between 300 and 750 m altitude, while the famous Chestnut Tree of One Hundred Horses on Mount Etna stands at 1200 metres.). They can tolerate maritime exposure, although growth is reduced.
Seeds germinate in late winter or early spring, but the life length is short. If kept moist, they 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 to sow them as soon as ripe, either in cold frames or seedbeds outdoors, where they 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.
Castanea grows best in a soil with good drainage and adequate moisture. The tree prefers sloping, deep soils; it does not like shallow or heavy soils with impermeable, clay subsoils. The Chinese chestnut prefers a fertile, well-drained soil, but it grows well in fairly dry, rocky, or poor soils.
Although Castanea can grow in very acid soil, and while these soils are reasonably well tolerated, the preferred range is from pH 5.5-6.0. It does not grow well on alkaline soils, such as chalk, but thrives on soils such as soils derived from granite, sandstone, or schist. On alkaline soils, chestnut trees can be grown by grafting them onto oak rootstocks.
Recently cleared land is best avoided to help resist the root rot, Armillaria mellia.
Castanea likes a full sun position. An experiment with Castanea dentata seedlings in Ohio confirmed the need for sun for optimal growth. The butt of the tree is sometimes painted with white paint to protect the tree from sunburn until it has developed enough canopy.
Wide spacing between the trees encourages low, broad crowns with maximum exposure to sunshine to increase fruit production. Where chestnut trees touch, there is virtually no fruit production. Current industrial planting spacings can range from 7 m x 7 m to 20 m x 20 m. The closer plantings, which are more popular, mean quicker increases in short-term production, but heavy pruning or even tree removal is required later.
The optimum rainfall for chestnut trees is 800 mm (31 in) or more per annum, ideally in even distribution throughout the year. Mulching during summer is recommended. Rainfall below 700 mm (28 in) per annum needs be complemented with, for example, a drip irrigation system. This should water the soil at the outer half of the circle formed by the drip line to encourage root growth.
Harvested from October through March, December is the prime month for fresh chestnuts. If you are unable to find them fresh, you can take advantage of chestnuts canned, pureed, or preserved in sugar or syrup (marrons glacés). Shelled and cooked nuts should be covered, refrigerated, and used within three to four days. Cooked chestnuts, either whole, chopped, or pureed, may be frozen in an airtight container and held up to 9 months. Because of their high water content, transpiration rates and consequent loss weight, the nuts react as fresh fruits (not as nuts). They should be kept cool at all times, including in shops when on display for sale. To preserve their freshness for a few months with no artificial refrigeration, the chestnuts can be soaked in cold water for about 20 hours immediately after harvest, after which they are dried in the shade, then layered in dry sand.
On the other hand, chestnuts behave similarly to seeds in that they produce very little ethylene, and their respiration rate is low, varying between 5 and 20 mg/(kg·h) depending on the temperature.
Most wood production is done by coppice systems, cut on a 12-year rotation to provide small timber which does not split as badly as large logs. In southern England (particularly in Kent), sweet chestnut has traditionally been grown as coppices, being re-cut every ten years or so on rotation for poles used for firewood, fencing (fence posts and chestnut paling) and especially to support the strings up when hops are grown.
An excellent soil-enriching understory in Pine forests Sustainable forest management incorporates more mixed plantings of proven efficiency, as opposed to monosylviculture. A study presented in 1997 has evaluated positively the potential increase in productivity with mixed stands and plantations, compared to plots of only one species. The relative yield total values of the mixed plantings steadily increase with time. It has shown that Castanea sativa responds well to competitive pressure from Pseudotsuga menziesii, the latter also showing a higher productivity. Another study with Castanea dentata seedlings in Ohio concluded that reforestation efforts is best achieved by planting it in places with little or no arboreous land cover, because of the need for light.
Another method of eating the fruit involves roasting, which does not require peeling. Roasting requires scoring the fruit beforehand to prevent undue expansion and "explosion" of the fruit. Once cooked, its texture is similar to that of a baked potato, with a delicate, sweet, and nutty flavour. This method of preparation is popular in northern China as well as in Portugal, Spain, Turkey, Greece, Italy, France, Slovenia, Croatia, Korea and Southeast Asia, where the scored chestnuts may be cooked in a tub of heated coal pebbles[clarification needed] mixed with a little sugar.
Chestnuts can also be peeled and deep fried. One advantage to this method is that any rotten nuts can be discarded at this stage. Deep fry using a basket until the nuts are just starting to float on the surface of the oil. Lift the basket out of the pan, keeping the lid on the basket. Shake the basket in a circular motion, then remove the lid and dry the nuts on newspaper or kitchen roll.
Chestnuts can be dried and milled into flour, which can then be used to prepare breads, cakes, pancakes, pastas, polenta (known in Corsica as pulenda), or used as thickener for stews, soups, and sauces. In Corsica, the flour is fried into doughnut-like fritters called fritelli and made into necci, pattoni, castagnacci, and cialdi.
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 can stay fresh for as long as two weeks.
The nuts can also be eaten candied, boiled, steamed, grilled, or roasted in sweet or savoury recipes. They can be used to stuff vegetables, poultry, fowl and other edibles. They are available fresh, dried, ground or canned (whole or in puree).
A fine granular sugar can be obtained from the fermentation of the juice, as well as a beer; the roasted fruit provides a coffee substitute. Parmentier, who among other things was a famous potato promoter, extracted sugar from chestnuts and sent a chestnut sugarloaf weighing several pounds 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.
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 went into a recession with the collapse of the textile market, notably silk. Clément Faugier ingénieur des Ponts et Chaussées was 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. One kilogram of untainted chestnuts yields about 700 g of shelled chestnuts.
Chestnut flavors vary slightly from one to the next, but it[clarification needed]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.
Chestnuts are often added to animal fodder. A first soak in limewater removes their bitter flavour, then they are ground and mixed with the ordinary provender. Other methods of preparation are also used. It is given to horses and cattle in the Orient, and to pigs in England, France and other places. Sheep will pop the chestnuts out with their hooves, when in pastures containing the trees. The leaves are not as prone to be insect-eaten as those of the oak, and are also used for fodder.
Chestnut is of the same family as oak, and likewise its wood contains many 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 slowly, although copper, brass or stainless metals are not affected.
Chestnut timber is decorative. Light brown in color, it is sometimes confused with oak wood. Both woods' textures are also similar. When in a growing stage, 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. The American chestnut Castanea dentata served as an important source of lumber, because that species has long unbranched trunks. In Britain, it was formerly used indiscriminately with oak for the construction of houses, mill-work and household furniture. It grows so freely in that country, 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 closely resembles chestnut in grain and colour.
It is therefore uncommon to find large pieces of chestnut in building structures, but it has 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 are cupboards cut directly from the hollowed trunk.
Dry, chestnut firewood is best burned in a closed log-burner, because of its tendency to spit on an open fire.
The tree is noted for attracting wildlife. The nuts are an important food for jays, pigeons, wild boar, deer, and squirrels. Several insects, notably the chestnut weevil Curculio elephas, also feed on the seeds. The leaves are used as a food plant by the larvae of some Lepidoptera species (butterflies and moths); see list of Lepidoptera that feed on chestnut trees. American and Chinese chinquapins (Castanea pumila and Castanea henryi) have very small nuts that are an important source of food for wildlife.
Chestnut wood is a useful source of natural tannin and was used for tanning leather before the introduction of synthetic tannins. On a 10% moisture basis, the bark contains 6.8% tannin and the wood 13.4%. The bark imparts a dark colour to the tannin, and has a higher sugar content, which increases the percentage of soluble non-tans, or impurities, in the extract; so it was not employed in this use.
Chestnut tannin has a naturally low pH value, relatively low salts content and a high acids content. It is one of the pyrogallol class of tannins (also known as hydrolysable tannin). As it tends to give a reddish tone to the leather, it is most often used in combination with quebracho, mimosa, myrabolans, and valonia.
The wood seems to reach its highest tannin content after the trees reach 30 years old. The southern European chestnut wood usually contains at least 10 to 13% more tannin than chestnut trees in northern climates. Today, the largest producer of extract for tanning is Italy.
Linen cloth can be whitened with chestnut meal.
|Look up chestnut in Wiktionary, the free dictionary.|
|Wikimedia Commons has media related to: Castanea|