The European chestnut (Castanea sativa Miller), in Italy most commonly called chestnut is a deciduous tree in the family Fagaceae. The species is the only native of the genus Castanea in Europe, but in recent decades has often been introduced for reasons phytopathological, the Japanese chestnut (Castanea crenata). The populations in Europe are therefore mainly related to European chestnut seedlings or grafted on Japanese or European chestnut hybrids of the two species. The chestnut is one of the most important forest species in southern Europe, as it has had, since ancient times, the interest of man for many uses. Besides the intrinsic interest in the ecological aspect, this species has been widely cultivated, up to a wider range, for the production of timber and fruit. The latter, in the past has been an important food source for the rural areas of mountain forest and hills, as the chestnuts were used mainly for the production of flour. The economic importance of the chestnut has now undergone a drastic downsizing: the fruit crop is now limited varieties of high quality and the production of wood for building was markedly reduced. Very marginal, finally, is the use of chestnuts for the production of flour, which has a minor use in the confectionery industry. It is believed that most of the chestnut forest cover were a result of renaturation of old abandoned plantations over time, while the cultivation has been reduced more favorable to the stations, where you can get the best characteristics of the product, including timber. The chestnut tree is a plant-limbed, with expanded, rounded crown height and variable, depending on conditions, from 10 to 30 meters. Under normal development of a large columnar trunk, with bark smooth, shiny, brownish-gray. The bark of the branches is white and is covered with transverse lenticels. Over the years, the bark cracks longitudinalmente.Le leaves are alternate, provided with a short stalk and, behind this, two stipules oblong. The foil is great, even up to 20-22 cm long and wide up to 10 cm, lanceolate, acuminate apex and serrated in the margin, with sharp teeth and regularly located. The young leaves are hairy, but fully developed are hairless, shiny and leathery texture. The flowers are unisexual, on the same plant. The male flowers are grouped in small clusters in turn forming catkins erect, 5-15 cm long, issued at the leaf axil. Each flower is white, features a perigonium divided into 6 lobes and an androecium of 6-15 stamens. The female flowers are single or in groups of 2-3. Each group is surrounded by a sheath of bracts that cupola.Il fruit is an achene, commonly called chestnut, with pericarp cuoiosa consistency and brown, glabrous and shiny on the outside, tomentose inside. The shape is more or less spherical, with one side flattened, said belly, and a convex, called back. The apical pole ends in a small prolongation fringed, said the torch, while the proximal pole, called the hilum, is slightly flattened and gray. The streaks are back more or less marked, particularly in the variety of the group of brown. These morphological features are important for recognition of the variety. The chestnut is a mesophilic and moderately demanding species in moisture. It supports quite well the cold winter, suffering damage only at temperatures below -25 ° C, but becomes demanding during the growing season. For this reason, the chestnut has a late vegetative growth, with bud and bloom in late spring to early summer. In order to complete the cycle of fruiting, the good weather should last almost four months. In general, these conditions occur in the plane of the submontane regions Mediterranean or low hill to the north. Under favorable moisture can also be grown in fresh Lauretum stations, going so at lower altitudes. Moderate summer drought conditions cause a slowdown in the vegetative half of the season and irregular fruiting. The persistent fog and excessive rainfall during June and July hinder pollination has negative repercussions on the early stages fruttificazione.Nelle tolerate moderate shade, done this, that promotes good regeneration in the forests mature, but in production shows a eliofilia.A more moderate face of climatic requirements, the chestnut has considerable needs soil, so its distribution is closely related to the geology of the area. Under the chemical and nutritional aspects, the species prefers well-endowed land of potassium and phosphorus and humus. Optimal conditions occur in neutral or moderately acidic soils, adapts well to push more acidity, while generally shuns the basic soils, as limestone is moderately tolerated in humid climates. From the point of grain size tend to prefer loose or loose soils, while clay soils are not tolerated, or at least prone to ponding. In general are preferred soils derived from volcanic rocks (tuffs, trachytes, andesites, etc..), But grows well in acidic soils typically derived from granite, sandstone, quartz, etc.., which are sufficiently endowed with humus. The limestone soils are tolerated only in the northernmost stations, moderate rain, while the marls are poorly tolerated.
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