94 TH POTATO 



periment Station 3 to 5 inches deep gave the heavi- 

 est yields, but 5 to 6 inches deep is recommended, as 

 tubers of better quality are produced. 1 While in a dry 

 season, on a rich clay loam soil, Green 2 , of Minnesota, 

 obtained better results from deep planting, the yields 

 being, per acre, planted on the surface, 216 bushels; 

 3 inches, 227 bushels ; 6 inches, 297 bushels ; 8 

 inches, 328 bushels, it was felt that the results would 

 have been different if the season had been wet. The 

 New Jersey Experiment Station 3 obtained similar re- 

 sults, but found a depth of 4 inches most profitable. 

 From the data submitted and other sources, 3 inches 

 to 4^ inches seems to be the most profitable depth. 4 

 On soils which are heavy and bake, and under certain 

 climatic conditions, the seed should be planted fairly 

 deep, but not covered more than 2 inches or so, to aid 

 germination. 6 The soil can then be gradually worked 

 toward the potatoes until level culture is obtained. 

 This system is sometimes advocated for the second 

 crop in the South. 6 



Influence of Depth of Planting on the Depth 

 at Which Tubers Form. This question is of im- 

 portance, because mechanical diggers must be used, 

 and it is essential to know the depth to which they 

 must work in order to dig all the crop. Zavitz, 7 of 

 Ontario, as the result of three years' trial, found that 

 on an average potatoes from tubers planted 



1 N. D. Report, 1901, p. 97. a Minn. Bui. 10, p. 74. 



3 N. J. Bui. 120, p. 10, and Botanist's Report, 1896, p. 318. 



4 Ga. Bui. 29, p. 304. Tex. Bui. 71, p. 7. 6 Pa. D. A. Report, 1902, p. 722. 

 6 Ga. Bui. 29, p. 305. 7 Ont. Agr. Coll. Farms Report, 1894, p. 98. 



