424 AGRICULTURAL ECONOMICS 



next decade from California where he is in the same business. 

 The method of driving sheep from Ohio to Texas is described 

 and in fact the student who has the time and ability can easily 

 reconstruct the whole movement of the sheep industry, from the 

 days when Vermont and New York led in this industry to the 

 present day with the Rocky Mountain states in the dominant 

 position. 



The story is only half told, however, until it is explained. To 

 explain these changes it becomes necessary to write the history 

 of the expansion of American agriculture. The competition of 

 the various farm enterprises has played an important part. The 

 result of this competition is determined by geographic factors. 

 Topography, climate, and nearness to the market are important 

 examples. 



In Vermont, New York, northeastern Ohio, and in Wis- 

 consin, wool growing was driven out by the dairy industry. 

 This is indicated by contemporaneous literature. Statistics of 

 the dairy industry were not collected in 1840, but the milk 

 production statistics as shown by the census for 19 10 indicate the 

 presence of this industry at the latter date in the regions which 

 were in the earlier decades important centers of the sheep in- 

 dustry. The economic principle involved is simple. Wool 

 is durable, dairy products are perishable. The value of wool 

 per pound is much greater than milk and has often been greater 

 than butter and cheese. The dairyman at a distance from 

 the market for dairy products cannot compete with the one near 

 the market so well as the shepherd in the distant hills and downs 

 can compete with the wool grower near the center of population. 



Beef cattle replaced sheep in Texas, the development of agri- 

 culture and fruit growing by irrigation was an important factor 

 in California, and tariff legislation played an important part in 

 forcing out the sheep in Ohio and Michigan during the nineties. 

 A careful study of the operation of competitive forces, with and 

 without artificial price levels, enables the student to discover the 

 workings of the economic laws which have wrought the changes. 



The geographical method. Farming in the various regions of 

 the United States shows a high degree of diversity. In one region 



