TEOUT PONDS 97 



fish where the water is the warmest, so as to 

 advance their growth as rapidly as possible. 

 Ponds for fingerlings should be so constructed 

 that the water-supply may be augmented and 

 decreased at will. No pond, however, should 

 be built at such a distance from the intake that 

 the temperature of the water would be so high 

 as to render necessary a very heavy volume, as 

 that is not good for trout in the first year of 

 their lives. 



Shading. — There ought to be a generous 

 space between at least every other pond so that 

 trees may be planted. Trees not only keep 

 the water cool in hot summer days, but also are 

 useful in that they breed insects which fall into 

 the water and furnish food for the fish. Wil- 

 lows are probably the best trees to plant for 

 this purpose, because of their rapidity of 

 growth, because their leaves do not make so 

 much dirt in the ponds as most other trees, and 

 because their long drooping branches and 

 slender leaves act as a fan, thus producing a 

 cool breeze on the hottest day in summer. The 

 only objection to the willow is that the fine 

 roots force their way in sponge-like masses 



