TABLES 



Page 



1. — Crop yields on level benches (Summary of three sets of experiments) 19 



2. — Maximum depth of cut for benches, by slope and bench width 19 



3. — Quantities of earth to be moved in construction of benches of varying widths, 



by slope 19 



4. — Land area occupied by dikes and backslopes (Percent of total area in a field). 19 



5. — Estimated construction cost per acre for benches of varying widths, by slope 20 



6. — Estimated alfalfa production per 100 acres on level benches, by slope and 



width of bench 20 



7. — Cost and returns from alfalfa on natural slopes and level benches, per 100-acre 



field on 4-percent slope 20 



8. — Net returns from alfalfa on level benches of varying widths and slopes (Per 



100 acres) 20 



9. — Cost and returns for spring wheat production on level benches (Per 100-acre 



field) 21 



10. — Terrace construction for which payment was made under the Agricultural 



Conservation Program in North Dakota, South Dakota, and adjoining states . . 21 



11. — Countour farming and stripcropping in North Dakota, South Dakota, and ad- 

 joining states, 1964 21 



FIGURES 



1. — Diagrammatic profile of level bench systems with and without contributing 



areas 2 



2. — Snow deposits on a level bench 4 



3. — Snowmelt water on a level bench 5 



4. — Layout of level bench system without contributing area 8 



5. — Layout of level bench system with contributing area 8 



6. — Relationship of alfalfa production and value to total water available 13 



IV 



