22 BULI^ETIiSr 1098, U. S. DEPARTMEIvrT OF AGRICULTUEE, 



cussion varied greatly at times, due to failure to make such provision. 

 HoTrever. from this variable level ^hich occurred, the experience was 

 gained that such fluctuation in level operated as an aid in the control 

 of the marginal vegetation which otherwise would have gained a foot- 

 hold and would have required an expenditure for the maintenance of 

 clean margins. The suggestions are made that the crawfish injury 

 can be prevented by a core wall through the center of the fill to 

 either side and below the box of the spillway in the dam, and that a 

 variable water level can be secured by a sluiceway, with control gate, 

 through the fill and core wall. 



Advantages to the plantation from the impounding work, apart 

 from the control of Anopheles breeding, are a permanent supply of 

 good water for live stock during the dry season ; an extension of the 

 land available for pasture : the deeper and more extensive water of 

 the impounded area, which offers a favorable place for game fish and 

 thus furnishes a source of food : and the lake-like body of water which 

 offers recreation to the plantation people and adds to the attractive- 

 ness and value of the property. 



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