May, 1913.] Control of Aquatic Resources. 141 



Thev could also be used in suitable localities for extensive systems 

 of inigation, and finally for the cultivation of aquatic crops. 

 Such crops, although at present problematical, have, I fully 

 believe, a most important promise of wealth. 



Considering, then, the quantity and regularity of our water, 

 the extent of the utilization it is already given, and the possibilities 

 in development for irrigation systems, power, and navigation, and 

 especialh' the possibilities of development for production of im- 

 portant crops, it is no extravagance to claim that it stands as one 

 of our greatest sources of wealth, and merits and demands thorough 

 scientific investigation that these resources may be conserved, 

 developed and utilized to their fullest extent. 



In summing up these different factors it seems that the greatest 

 utility of our water supply and its most effecti'\-e control may be 

 secured \^'ith the combination of a number of different methods, 

 but not by depending upon any single one. The following may be 

 offered as suggestive: 



First, the levee system serving to narrow and raise a river 

 channel, can serve only to jeopardize the lives and property of 

 the river valley and should be resorted to only in particular 

 cases and in connection with other means of flood relief. 



Second, the establishment of as many reservoirs as possible, 

 in the head waters of the smaller tribute ries to the larger streams 

 and the utilization of such reservoirs not only for power and as a 

 reserve for water supply, for irrigation and navigation, but also 

 as a basis for the growth of aquatic plants and animals, the cul- 

 tivation of which should be a subject of careful experiment. 



Third, the exhaustive study and development of reforestation 

 wherever this can be done to advantage, and especially the pro- 

 tection of thickets and brush land along the slopes leading to the 

 river bed. 



Fourth, the preservation an.d regulation of all extensive 

 swamp areas which can be made to contribute to water retention 

 in the head waters of the river tributaries. 



Fifth, the extensive planting of marsh grass, willows, or an}^ 

 other plants which flourish in the river bottoms, as a means of 

 checking the flow to the streams during periods of excessiv^e 

 rain. 



Sixth, the utilization of the river flood plains reached by higher 

 floods for crops which are least affected by over-flows of river 

 water and which provide an opportunity for the spreading out of 

 excessive water and serve also to catch and hold the river silt 

 which forms a most important addition to the soil's fertility. 



