1166 EARLE V. HARDENBURG 



legume productive of considerable vegetative growth, as a crop to precede 

 potatoes. This is evidence of the efficient use which the potato crop is 

 able to make of this form of organic material. Such legumes as cowpeas, 

 soybeans, and crimson clover commonly precede potatoes in the Southern 

 and the South Atlantic States, while timothy, in combination with red or 

 alsike clover, is used generally thruout the principal potato States. Alfalfa 

 is considered the ideal legume to precede potatoes in the alfalfa belt of the 

 West. The root and stubble residue from these crops not only contributes 

 to the food requirements of the potato, but also improves the aeration, 

 the temperature, and the moisture-holding ability of the soil. 



Generally speaking, the rotations of the three regions aside from Long 

 Island are long enough not to serve as factors limiting yield except as the 

 type of rotation may affect fertilizing practices. Inasmuch as the avail- 

 able stable manure is not usually applied for the benefit of the hay crops, 

 and the residual organic fertility is not thereby maintained or improved, 

 the sod residue commonly turned under before potato planting is usually 

 less Valuable after a three-years stand than after a stand of shorter 

 duration. 



VALUE OF LAND 



The farmer's estimate of farm land values is very often not based on 

 productive value, altho this factor, together with the distance from rail- 

 road and city and the salability of the farm, usually enters into the appraise- 

 ment. A correlation of estimated value with average yields will show, 

 in a measure, the extent to which productive ability of potato land enters 

 into its evaluation. App (1916), studying the factors that influence 

 farm profits on potato farms in Monmouth County, New Jersey, found a 

 consistent tendency for farm acre values to decrease as distance from the 

 railroad increased. His similar conclusions with respect to crop acre 

 values and labor income, however, do not seem warranted from the data 

 given. 



The figures obtained on land values in the regions surveyed represent 

 the estimated selling value of potato land only. A more important factor 

 than the distance from the post office, which was ascertained and used 

 in making this estimate, would have been that of the distance from the 

 nearest city, village, or railroad. 



Apparently, on Long Island, land valued up to $550 an acre is yielding 

 an increased crop with the increase in value (table 9). However, it is 

 true also that the increase in land values is accompanied by the use of 

 more seed and more fertilizer, and by more spraying for blight. These 

 combined factors would easily account for the consistent increase in yield. 

 The farms showing a land value of over $550 an acre are located prin- 

 cipally in Nassau County, at a considerable distance from the post office, 

 and are appraised at their real-estate value. In fact, much of the land 

 has been sold at fabulous prices for real-estate purposes and is now rented 



