6l2 



Yearbook^ of Agriculture 1949 



bility for their maintenance or for 

 Federal supervision of their mainte- 

 nance by other than a Federal agency. 

 Survey reports indicate the proposed 

 maintenance responsibility for the 

 recommended types of remedial meas- 

 ures, together with the cost-allocation 

 estimates. 



As a means of testing effectiveness 

 of the watershed programs and im- 

 proving knowledge of watershed func- 

 tioning, survey reports often provide 

 for measuring the effects of the work 

 upon flood flows, sedimentation, soil 

 deterioration, and other factors in 

 sample subwatersheds. 



WATERSHED PROGRAMS consist of 

 such measures as the improvement of 

 existing vegetative cover, the establish- 

 ment of trees or other vegetation on 

 denuded areas, and the protection of 

 forests and grasslands from fire. They 

 include the adoption of the best prac- 

 tices for the management of livestock 

 and big game and of logging and 

 forest-management practices that will 

 maintain a good ground cover. They 

 foster the proper use of close-growing 

 and cover crops on tilled lands and 

 such changes in land use and plant 

 cover as will increase water absorption 

 and retention in the soil and improve 

 the soil storage capacity and crop pro- 

 duction. 



Still other measures include such 

 soil- and water-conserving practices as 

 contour cultivation, strip cropping, 

 and supplemental mechanical devices 

 or structures, like terraces, diversion 

 ditches, check dams, small detention 

 dams, and debris basins. 



Whether the land is privately or 

 publicly owned, the watershed-treat- 

 ment programs are planned entirely by 

 subwatersheds, with the various meas- 

 ures coordinated to obtain the maxi- 

 mum effectiveness of the work. Such 

 measures as fire control, range reseed- 

 ing, detention dams, debris basins, and 

 stream-bank stabilization are installed 

 only on a subwatershed basis because 

 of the nature of the improvements and 

 because several types and ownerships 



of land are often involved. However, 

 many measures (such as adjustments 

 in use of land within farms, vegetation 

 of farm pastures or woodlands, ter- 

 races, strip cropping, and contour 

 farming) are installed on a farm-by- 

 farm basis. 



Altogether, the job of watershed 

 treatment and management is one in 

 which individuals, organizations, and 

 local, State, and Federal Governments 

 are concerned and from which all de- 

 rive flood protection and other bene- 

 fits of physical, economic, and social 

 value. 



Unless all parts of a watershed area 

 are in good condition, damaging 

 floods, erosion, and sedimentation may 

 still occur. Unsatisfactory conditions 

 on as little as 1 or 2 percent of a water- 

 shed may cause serious losses. It is of 

 the utmost importance that the pro- 

 gram for any watershed be considered 

 as a whole. Although partial programs 

 may help, the maximum possible re- 

 duction in flood and sedimentation 

 damages and the greatest economy in 

 expenditure can best be achieved by 

 complete and unified application. That 

 is the key purpose for which the pro- 

 gram is designed, and that is the basis 

 upon which it must be applied and 

 maintained. 



To obtain the maximum beneficial 

 effects from a watershed-improvement 

 program, installation should be sched- 

 uled on an orderly basis. In the case 

 of the 1 1 programs already authorized 

 by Congress, the periods specified in 

 the survey reports vary by watersheds 

 from 10 to 24 years. The estimated 

 costs of installation and the expected 

 beneficial effects of the programs out- 

 lined in the reports are geared to the 

 specific installation periods. To the 

 extent that delays occur in installing 

 the programs, further watershed dete- 

 rioration can be expected. Thus, the 

 more the work is delayed, the greater 

 will be the costs of installing the meas- 

 ures, and the longer it will take for 

 them to achieve full effectiveness. 



Two units of the Department of 

 Agriculture, the Forest Service and 



