100 



Congress at Milan in which Wdll'scliiitz dl' lU-iinn yave prodf to show that 

 the efficacy of the forest in retarding water fails in times of lon.i^-continued 

 and extraordinary rain, and Ilonsoll claims that the best wooded basins 

 of the Black Forest, Ilarz, Spessart, etc., contributed most of the water 

 of tlie floods of the Rhine in 1882. Like experiences were reported from 

 the watersheds of the l^lbe in 1897, of the rivers Enns, Traun and Ybbs in 

 1899, and from the densely forested Itiesenwald in Silesia in 18SS, 1897 

 and 1903. Wolfschiits, however, tbinks that forests have a limited and 

 local influence in certain regions in reducing floods. Landa, director of 

 the Austrian Hydrographic Bureau, conies to the conclusion that weather 

 conditions i)receding the precipitation lia.s a bearing on forest influences, 

 the forest having the greater retentive capacity after a drouth. Pouti, 

 an Italian engineer, asserts experiences of increased floods due .to de- 

 forestation in Sardinia, Sicily, and Camrx)basso, and of the watersheds of 

 Adda and Matero. He also finds favorable influences from forest planting 

 in several provinces. The Russian, Lokhtine, cites a long series of gen- 

 eral experiences and observations from i)arts of Europe and especially 

 from Russia which indicate injurious effects from deforestation. Other 

 instances were given which show that the water level is decreasing with 

 deforestation. 



After considering these and nuu-h additional testimony on the subject, 

 one is justifled in saying that forests do act as great regulators of rain- 

 fall but that their value in this respect is a relative one which is modified 

 by many conditions. 



Forests and Watki: Level. 



Let lis now consider the relation of forests and water \v\v\ as shown 

 by observations and experiments. 



Profes-sor Biihler [see (7)1 foun<l a nuicli lower ground water level 

 under forest growth than in the meadows. Ototsky in the steppes of 

 Russia, where a low rainfall prevails, came to the same conclusion as 

 Biihler. Eliormayer and Ilartman in Bavaria, however, found no differ- 

 ence between the ground water level of forest and tield. Otoski states 

 that Wollny and King found the ground water level lowered by a forest 

 and that tliis caused its lowering in adjaecMit open soil. In a bulletin 

 by A. Tolsky and K. Henry (KM it is shown that observations made inde- 

 ]iendt'ntly in France, near .Nancy, and those made in the Knssian Steppes 



