6 DEPARTMENT OF AGRICULTURE BULS. 976-1000. 



Department Bulletin No. 996. — Flushing and Other Means of 



Increasing Lamb Yields : Page. 



Extent to which flushing is practiced in the United States 1 



Factors influencing size of lamb crop 2 



Results of experiments in flushing ewes 3 



Twin production as affected by age of ewe 7 



Twin production as affected by breed of ewe 8 



Twin production as affected by sire 8 



Breeding for twin lambs 9 



Value of twin lambs in comparison with singles 10 



Comparative weights of single and twin lambs 11 



Summary 13 



Department Bulletin No. 997. — The Cost and Utilization of Power 

 on Farms Where Tractors Are Owned: 



Introduction 1 



Summary 2 



Areas in which investigation was made 5 



Size and age of tractors 9 



Work stock 10 



Size of farm 11 



Size of farm and size of tractor 12 



Work stock on farms of different sizes 12 



Work done by tractors 13 



Drawbar work 15 



Belt work 24 



Custom work 25 



Work done by horses 26 



Horse labor equivalent of tractor work 34 



Proportion of work done by horses and by tractors 35 



Number of work stock used on different operations 37 



Cost of keeping work stock 39 



Cost of using tractors 45 



Reliability of tractors 53 



Cost of power for different operations as furnished by horses and 



by tractors 54 



Annual cost of power for drawbar work 54 



Changes in size of farm and number of work stock after purchase 



of tractors 56 



Increase in investment due to purchase of tractors 59 



Saving of man labor due to use of tractors 60 



Department Bulletin No. 998. — Effect of Borax in Fertilizer on the 

 Growth and Yield of Potatoes : 



Purpose of the investigations 1 



Plan of the experiments 2 



Results of the experiments 3 



Rainfall record 6 



Summary 7 



Literature cited 8 



Department Bulletin No. 999. — Prices of Farm Products in the United 

 States : 



Rise and fall in prices during three war periods 1 



Money and prices 5 



Relation of weather to production 6 



Periods of over and under production 7 



Relation of wages and farm prices 10 



Wholesale prices of farm products during the Civil War and World 



War periods 12 



Prices paid to farmers 14 



Comparison of farm prices with prices of some other basic com- 

 modities and with freight rates 16 



Comparison of farm and wholesale prices 17 



Purchasing power of farm products 19 



Purchasing power per acre 20 



Effects on industry 22 



