(This page was automatically translated from German. Echter Hausschwamm)
Fungi play an important role in the household of the nature and close the material-cycle so. They disintegrate a multiplicity of organic (vegetal) materials into its mineral elements so that no larger conglomeration of an organic link is to be found. The degradation takes place in the respiration-metabolism with oxygen. The organic elements serve as energy and carbon-sources. Cellulose, lignin, are fitting proteins, pectin, lipids, keratin and other, to these complex natural materials. The size of the fungi is not recognizable through the fruit-bodies, but the main-part of the fungus consists of the hidden mycelium. The individual hyphas of the mycelium, from which the fruit-bodies is created, are usually microscopically thin. They also can thicken, however, and root-like cords form and very severe lengths reach. In the U.S.-state Washington, it turned 1992 one at tree-roots parasitierender Hallimasch (Armillaria ostoyae) found, that the expansion of over 600 ah had. another Hallimasch was revealed to 2000 in the U.S.-federal state Oregon whose mycelium is enough deeply until 90 cm into the earth and an expansion of about. 880 ah has. The age of the fungus is estimated at 2400 years. Its bulk clearly should exceed those of a blue whale. [Beautifully] It therefore is not remarkable, why dry rot the length of the mycelium from the without problem 12 m or can reach even longer.
The affection for wood-destructive fungi and insects requires other nutritional-substances (albumin, fat) an elevated humidity, carbon-links as an energy-trade creditor, for example in the wood cirka a share from until 5 per cent, as well as trace elements (different cations and anions).Further different environmental influences and also the pH value play a role. In accordance with the DIN 1052 (timber construction) the balance dampness for woods in generally closed areas with heating 6-12% and unheated areas 9-15% should amount to. This humidity should be kept also with the new installation by felling trees hurrying. In the following table the beginning of the growth of different kinds of parasit is represented.
|wood-damaging mushrooms||5ºC||13 - 30%|
|0 - 40ºC||(15) 20 - 80 (100)%|
|wood-destructive insects||10 - 38ºC||10 - 60 %|
An exact statement, when a wood-destructive mushroom develops, out-germinates thus for traces or begins Myzelreste to grow, cannot be determined clearly. There are certain frontiers (designated in the following remarks), which are exceeded in practice generally kept in addition, under certain circumstances. Couches optimal conditions, humidity, temperature, food basis among other things forwards, then the probability of an infestation is large. Or if two of the important conditions are missing, then no growth can take place and/or a rigidity process changes and dies the only weakly trained Myzel sometime into. A substantial factor is also the length of time, where optimal conditions are present. The results determined on laboratory conditions cannot be transferred so easily to variant-rich practice, whereby these certain trends point out.
With the numerous examined cases of damage by the majority also the genuine dry rot stopped its growth. In other places living person infestation was present, although apparently no outward conditions were present. The cause emergence was past partially years. The list of systematics, when and on which condition a growth takes place, can because of the large dispersion are not set up, and/or which do not leave themselves won results both from adhesion questions and economic considerations in practice to use surely. There is a number of different appearances and experiences, which can be consulted for the general evaluation. These will represent in the following to sections. The genuine dry rot ranks among the building timber mushrooms which can be fought most with difficulty. It represents an only with difficulty assessable risk and is considered therefore as substantial lack after BGB § to 459.
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