PERIODICAL LITERATURE 



SILVICULTURE, PROTECTION, AND EXTENSION 



Discusses red rot (Trametes radiciperda) on 

 The Red spruce near Schongau. This is a morainal re- 



Rot gion, with the tertiary sub-layer exposed along 



canyons, and with considerable areas of high 

 moor between the moraines. The morainal deposits weather into a 

 fresh, sandy loam, which with the heavy precipitation (1,250 mm.) is 

 very favorable to forest growth. Where the loam is shallow or cut off 

 by clay at a depth of 10 cm., moors are likely to form. The best timber 

 is on the "hard" soils, while that on the "soft" (moor) soils is not as 

 good. Spruce comprises 95 per cent of the stand, associated with beech 

 and fir on the "hard" soils and with alder and birch on the "soft" soils. 

 Mayer disagrees with Sauer's theory that red rot was favored by re- 

 moval of the beech from the spruce stands, and that pole-stands now 

 heavily infested were formerly healthy stands of spruce. He says the 

 rot was always present, but not noticed until wood prices became high, 

 and besides there is as much beech in the mixture as there ever was, or 

 even more. Figures show more rot on sites where beech or other hard- 

 wood species are present, than in pure spruce stands. Statistics of rot 

 per cent in conifers cut during six years (1912-1917) show a gradual 

 decrease in per cent of rot from 14.4 in 1912 to 10.6 in 1917, due prob- 

 ably to the institution in 1908 of a system of thinnings which take out 

 old defective trees as well as young trees. Then, too, the practice of 

 bringing the wood out to roadsides in winter eliminates much of the 

 rot injury which formerly occurred. In general, per cent of rot in- 

 creases with decrease in soil-moisture ; the average for "hard" soils was 

 12.7 per cent, and for "soft" soils 7.1 per cent. Contrary to Sauer's 

 assertion, boggy sites are not especially liable to infection, nor do the 

 figures show rot to be any worse in the first rotation on reforested 

 land which had been used for agriculture. Spruce roots develop very 

 differently on "soft" and on "hard" soils. On moors, the root mass is 

 barely 20 cm. thick and covers 30 square meters or more, with numer- 

 ous root masses at the periphery, called "paws" (tatzen) by wood- 

 choppers. These are not due to the presence of beech, since they are 

 common where there is no beech, but are caused by soil conditions. 

 Neither is the dying off of the older roots of spruce retarded by the 

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