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Encyclopedia of biodiversity encyclopedia of biodiversity, (7 volume set) ( PDFDrive ) 2925

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Land-Use Patterns, Historic 573 Figure A coppice wood The foreground has just been felled, leaving the stools from which new growth will arise In the middle is an area of years’ growth since last felling An older part of the wood forms the background Bradfield Woods, Suffolk, England nonforest – solely by people using up the trees Normally they would cut the trees suitable for the purpose in hand and leave the other trees The result would be a depleted forest, unsuitable for that purpose until a new generation of trees had grown This is not to be confused with a destroyed forest Great trees not easily furnish wood for fuel and timber for construction A big tree, when cut down, is a very intractable object Until the coming of sawmills, vehicles, and railroads capable of dealing with giant trees, people preferred to use the smallest log that would serve the purpose and to manage forests to produce a succession of trees small enough to handle Coppicing is an important factor Most European and North American trees, other than conifers, survive being cut down and sprout from the stump Clonal trees, like European elms and American beech, sucker from the roots Coppicing is one of the world’s most important practices in historic forest management By cutting down woodland every 5–30 years and allowing it to grow again from the stumps, a permanent succession of small stems can be assured, of sizes that are easily handled and suitable for light construction and fuel It was often the practice to leave a scatter of trees of selected species to grow on for three or four cycles to yield constructional timber (Figure 5) Coppicing has been the nearly universal woodland management in Britain, well documented for the past thousand years and known on archeological evidence for some 6000 years It is the basis of historic forest management in many parts of the broad-leaved and Mediterranean zones of Europe and also in Japan It was apparently not much practiced by Native Americans but was widely introduced by European settlers in America, where there are large areas of ex-coppiced wood-lots Coppicing affects biodiversity by drastically reducing the shade at the start of each cycle of felling and regrowth Two or three years of relatively open conditions follow, ending as the new growth closes in This favors various woodland plants and animals Low-growing herbs such as species of Viola and Primula flower in abundance in the years of extra light (Figure 6) Others such as Euphorbia species appear from buried seed produced by their parents at the last felling Many insects feed on the leaves or nectar of these plants The middle stages of regrowth, when there is a thicket of young stems, favor warblers and similar small birds – a famous English example is the nightingale (Luscinia megarhynchos) The dormouse (Muscardinus avellanarius), an English woodland mammal, favors the later stages Coppicing is often thought to be artificial, but the ability to coppice is widespread among the world’s trees and presumably was an adaptation to some process in wildwood Sometimes it is a response to fire, but it is not correlated with flammability: few pines (among the world’s most flammable trees) will coppice, but fireproof trees such as elms and poplars coppice or sucker American, European, and Japanese species of Tilia (lime, basswood) are self-coppicing and grow naturally in a multistemmed form; so American and Japanese species of Magnolia Possibly coppicing behavior is an adaptation to tree-breaking mammals: the axes of woodcutters are a replacement of the missing elephants, etc The author has observed something like a coppicing ecosystem developed in eucalyptus forests in New South Wales after only the third or fourth successive logging (Figure 7) Another historic woodland practice is the creation of permanent edges and open areas In England, wood-lots have permanent edges (many of them are over a thousand years old) defined by banks and ditches, constructed as a conservation measure (Figure 8) They may also have permanent tracks and other open areas in the interior In a typical woodlot, well over half the plant species are associated with the boundary, with recently felled areas, or with permanent openings The species of permanent openings tend to constitute plant communities of their own, distinct from those of

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