REVIEWvS 



71ie Effect of Forests Upon Strcamfloiv. Untersuchungen uber den 

 Einfluss des Waldes auf den Stand der Gewasser, von Dr. Arnold 

 Engler, Mitteikingen der Schweizerischen Zentralanstalt fur das 

 forstliche Versuchswesen, Zurich, 1919. 



Switzerland is a country of mountains with many villages nestling 

 among them. Close watch must therefore be kept on the mountain 

 torrents which often carry in their wake destruction of life and prop- 

 erty. As in our own country, the general experience of the people 

 who lived long in the woods and of foresters who observed the be- 

 havior of streams rising in forested and unforested watersheds was 

 that the forest has a beneficial influence upon the flow of water in 

 mountain streams. The need for strict protection of the mountain 

 forests was fully recognized and enacted in national legislation. There 

 were, however, many timber owners who were bent upon clear or 

 careless cuttings of the forests in the mountains because of the im- 

 mediate higher profits from such handling of their timberlands. There 

 were not a few engineers who sincerely believed that the influence of 

 the forest upon the occurrence of floods and the flow of water in the 

 streams was unduly exaggerated and were chafing under the restrictive 

 forest laws. In order to settle the question of the influence of the for- 

 est upon streamflow the Forest Experiment Station at Zurich in 1900 

 undertook accurate measurements on two small watersheds in the 

 Commune of Sumiswalde, about 15 miles northeast of Berne. In the 

 summer of 1910 a similar project was instituted by the U. S. Forest 

 Service in co-operation with the Weather Bureau in the Central Rocky 

 Mountains at Wagon Wheel Gap, Colorado, the Swiss experiment in its 

 broad outline being used as a model. In equipment and the methods 

 of carrying out the observations and in working up the records, how- 

 ever, as well as in the character of watersheds themselves, there were 

 essential differences. Some of these differences are brought out in the 

 course of this review. The Swiss Experiment Station, after 18 years 

 of continuous observation, has just published its results as worked up 

 to date. It is by far the most conclusive record which forest or 

 engineering literature has so far produced. Its particular value lies 

 in the analysis of the individual factors which affect the regime of 



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