. Bulletin. Forests and forestry -- United States. confine themselves to eating up the starch found in the cells, as shown in fig. 36, and merely leave a stain (bluing of lumber). In all cases of decay we find the vegetative bodies, these slender threads of fungi, responsible for the mischief. These fine threads are the vegetative body of the fungus, the little shelf is its fruiting body, on which it produces myriads of little spores (the seeds of fungi). Some fungi attack only conifers, others hard woods; many are confined to one species of tree and perhaps no one attacks all kinds of wood. O
. Bulletin. Forests and forestry -- United States. confine themselves to eating up the starch found in the cells, as shown in fig. 36, and merely leave a stain (bluing of lumber). In all cases of decay we find the vegetative bodies, these slender threads of fungi, responsible for the mischief. These fine threads are the vegetative body of the fungus, the little shelf is its fruiting body, on which it produces myriads of little spores (the seeds of fungi). Some fungi attack only conifers, others hard woods; many are confined to one species of tree and perhaps no one attacks all kinds of wood. One kind produces "red rot," others "' In one case the decayed tracts are tubular, and in the direction of the fibers the wood is "; In other cases no particular shapes are discernible. Cutting off a disk of loblolly pine, washing it, and then laying it in a clean, shady place in the sawmill, its sapwood will be found stained in a few days. Sor is this mis- chief confined to the sur- face ; it penetrates the sapwood of the entire disk. From this it appears that the spores must have been in the air about the mill, and also that their germination and the growth of the threads or mycelium is exceedingly rapid. (Watching the progress of mold on a piece of bread teaches the same thing.) Placing a fresh piece of sapwood on ice, another into a dry kiln, and soaking a few others in solutions of corrosive sublimate (mer- curic chloride) and other similar salts, we learn that the fungus growth is retarded by cold, pre- vented and killed by temperatures over 150° F., and that salts of mercury, etc., have the same effect. The fact that seasoned pieces if exposed are not so readily attacked by fungi shows that the moisture in air-dry wood is insufficient for fungus growth. From this it appears that warmth, preferably between 60° and 100° F., combined with abundance of moisture (but not immersion), is the most important condition favoring decay, and t
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