584 



Yearbook^ of Agriculture 1949 



ing purposes on which no dams would 

 ever be permitted. Another answer 

 being considered is to develop lower 

 tributaries that remain unblocked into 

 spawning and nursery streams for 

 salmon and steelhead. Many of the 

 headwater tributaries lie within the 

 boundaries of the national forests, 

 where long-range land- and water- 

 management plans aid these resources. 

 A major weakness of many of the 

 basin-wide water-development pro- 

 grams is that of starting work at the 

 wrong ends of our rivers. Water con- 

 trol should begin in the headwaters 

 where the rains fall and the streams 

 originate. 



WATERS OF NORMAL STREAMS are 

 supplied mainly by seepage from rain- 

 fall stored in soils. Denuded soils can- 

 not efficiently hold back rainfall and 

 melting snow. With rapid runoff from 

 eroded lands, heavy floods occur and 

 cause millions of dollars' damage an- 

 nually. Floods often are followed by ex- 

 tremely low stream flows in summer, 

 springs dry up, and ground water is 

 reduced. Excessively high water tem- 

 peratures usually accompany low flows 

 and in both the East and the West 

 thousands of miles of potential trout 

 waters have been eliminated by this 

 cause alone. 



Most of us have observed that in 

 areas where fires are controlled, where 

 good practices are followed in graz- 

 ing forest and farm lands, and where 

 sufficient ground cover remains to hold 

 the soil in place, the streams produce 

 the best angling. On watersheds where 

 good upstream management is prac- 

 ticed, extremes of flows in winter and 

 summer are avoided. Where poor land 

 management, ill-planned cutting, for- 

 est fires, or forest practices deplete the 

 cover of headwater basins, the result- 

 ing increase in rate of discharge car- 

 ries topsoil downstream in flash floods, 

 scouring out aquatic life and reducing 

 the productivity of streams for years 

 to come. 



Rains that follow forest fires some- 

 times pour large quantities of ash and 



other debris into streams and make 

 them strongly alkaline so that fish are 

 killed. Spawning beds become clogged 

 with silt and eggs, and fish foods are 

 destroyed. Logging debris left in the 

 streams and piled into huge log jams 

 by floodwaters can completely block 

 off access by fish to their upstream 

 spawning grounds. The clear-cutting 

 in past years of the Douglas-fir forests 

 in the West has harmed many trout 

 waters, and conservation agencies are 

 faced with a major problem in keep- 

 ing migratory routes open and free 

 from log jams. 



Good watersheds are popularly as- 

 sociated with mature forests, but they 

 may not necessarily be the most effi- 

 cient watershed cover because trees in 

 dense stands intercept snow and rain 

 and much of the moisture therein may 

 be evaporated before it can reach or 

 enter the soil. Trees, both large and 

 small, soil litter, herbaceous vegetation, 

 and grasses can be manipulated by 

 man; climate, soils, and underlying 

 geological formations cannot. 



It is good to write that forest prac- 

 tices initiated by several agencies in 

 connection with logging operations on 

 public lands are doing much to correct 

 the poor practices we have described. 

 The distributed cutting of small blocks 

 of timber, leaving ample seed-tree 

 plots, saving streamside strips, elimi- 

 nating logging across or down streams, 

 removing or burning slash, and other 

 corrective measures are doing much to 

 preserve our national aquatic values. 

 Destructive logging is not universal or 

 necessary. Our forests can be harvested 

 in a way that works a minimum of 

 harm to fish life. 



From the standpoint of maintenance 

 of good trout waters, it is quite pos- 

 sible to increase flows through proper 

 logging and manipulation of timber 

 stands. It is possible to have good trout 

 waters when watersheds are conserva- 

 tively used by domestic livestock in 

 grassy and browse-covered areas. Most 

 important is the degree of use made 

 of these resources. Herein lies the dif- 

 ference between proper and exploitive 



