XVIII -ON POND-FISHERIES. 



By Von dem Borne. 



An address delivered October 9, 1878.* 



[From Circular No. 6, 1879, of the. Deutsche Fisclierei-Verein, Berlin. December 31, 



1879.] 



After having given statistics of the pond fisheries in the Prussian 

 provinces of Lorraine, Silesia, Posen, and Scbleswig-Holstein, Mr. von 

 dem Borne goes on to say : 



" The facts which I have mentioned justifying the conclusion that the 

 pond fisheries deserve the attention of the farmer to the highest de- 

 gree. 



" The net profit is very considerable, and the expense is comparatively 

 small. It is therefore scarcely probable that there will be any loss, as 

 is so frequently the case in other farming operations. 



" The ponds produce manure, while the fields consume it. The water 

 flowing into the ponds forms layers of manure and feeds a number of 

 aquatic plants, which form a highly valuable substitute for straw. 



" The shores produce grass, which, however, does not yield any great 

 profit, because it is mostly sour, and, in order not to disturb the carp, 

 has to be cut very carefully. 



" The mud which gradually gathers at the bottom of ponds contains 

 much vegetable and animal matter, and, according to its chemical com- 

 position, forms a more or less valuable article of manure. Meadows lying 

 lower than ponds may be successfully iertilized by irrigating them by the 

 muddy pond-water. The mud from ponds is also an excellent fertilizer 

 for fields. 



" Ponds may also become a source of income to the farmer by being 

 cultivated while lying dry. They furnish a large quantity of manure 

 for the fields. While lying dry ponds are usually planted with grass 

 or oats, but also with potatoes, hemp, summer wheat, and beets. Dur- 

 ing the first years after having been laid dry the ponds need no manure 

 whatever. 



" Like forests, ponds also exercise an influence on the climate, and 

 this influence will be in proportion to their size. The former director 

 of the Principality of Trachenberg (Silesia), Mr. Frieboes, has informed 

 us that fields in the neighborhood of ponds always had more moisture 



*Yon dem Borne, "Ueber Teichmrtli8chafV > — [Translated by Herman Jacobson.] 



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