tUbAK lULLIS 



251 



The question as to the injuriousness of the Hack colored water flozmng 

 on to the meadozvs from the alder hogs of forests has been treated in detail 

 by Klien^. In one especial case which gave rise to complaints against the 

 forestry commission, the water coming from the forest was viscid, brown and 

 at times smelled bad. In 100,000 parts, it contained 31.28 parts organic sub- 

 stances (humic acids, etc.) and 17.59 parts mineral substances, among others 

 7.81 parts calcareous earth, 3.07 parts ferric oxid, etc. The humic acids 

 formed the injurious factor here. In similar cases it depends on the kind of 

 soil overflowed by such bog water. It will be especially injurious if it flows 

 over ferruginous soils or those with a clay subsoil, while a soil rich in lime 

 can more easily withstand overflowing from the alder swamp, such as oc- 

 curs in spring floods, because of the hastened decomposition of the humus, 

 peculiar to such a soil. Nevertheless such water should be avoided for irri- 

 gation and back water. 



The formation of ferruginous sand depends on the precipitation of fer- 

 ric hydrate and iron silicates. Mixtures of ferric hydrates with varying 

 amounts of ferric silicates and phosphates also give the so-called meado-m- 

 ore. This combination occurs in moors, standing bodies of water and other 

 places, where water containing iron comes in contact with the air, together 

 with the co-operation of bacteria (iron bacteria according to Winogradski)-. 

 One is inclined of late to lay stress on the co-operation of the micro-organ- 

 isms^ 



Susceptibility to Frost of Moor Vegetation. 



In moor soils which have been brought under cultivation, their especial 

 sensitiveness to frost as compared with other kinds of soil has been proved 

 by repeated experiments. In this, important differences are found if the 

 moor soil has a sandy covering or if it is mixed with sand. Wollny* found 

 in his experiments that the latter is more fertile than the former, in which 

 the ground water was higher. Instead of the sand, a covering with clay has 

 also been proved to be beneficial. In meadow cultivation when too much 

 water has been removed, Fleischer'' recommends covering with sand, rich in 

 feldspar, or loam, or clay to avoid too great drying out. Jungner*^ gives fur- 

 ther examples from the province of Posen. In them moor fields which had 

 not been covered with soil containing clay, showed also a second total freez- 



1 Klien, Die nachteiliqe Einwirkung- dps aus Eller-Briichen und Torfmooren 

 kommenden schwarzen Wassers auf die Wiesen. Konigsberger land- und forst- 

 wirtschaftliche Zeitung- 1879, No. 28; cit. in Biedermann's Centralbl. f. Agrik- 

 Chemie, 1880, p. 568. 



2 Winogradski, Ueber Ei&enbakterien. Bot. Zeit. 1888, p. 260. 



3 E. Roth, Die Moore der Schweiz, unter Beriicksichtigung der gesamten Moor- 

 frage. Leopoldina, 1905, No. 3, p. 34. 



4 Wollny, Untersuchungen tiber die Beeinflussung der physikalischen Eigen- 

 schaften des Moorbodens durch Mischung und Bedeckung mit Sand. II. Mitteil. 

 Forsch. a. d. Geb. d. Agrik.-Physik. 20. 1897-1898, p. 187. 



5 Fleischer, M., Ueber die zweckmafsige Behandlung von Moorwiesen; cit. 

 Biederm. Centralbl. f. Agrik.-Chemie, 1888, p. ] 37. 



6 Zweiter Jahresber. d. Sond.-Aussch. f. Fflanzenschutz fur 1904. Arbeit, d. 

 Deutsch. Landw.-Ges. Part 107, Berlin, 1905, p. 61. 



