PLANTING 93 



loam. This would result from rows 30 inches apart 

 with plants 1 2 inches asunder. In the United King- 

 dom my observation is that 2 7 -inch rows with plants 

 12 to 15 inches asunder for late varieties and 8 to 12 

 inches for early (Fig. 23) and second early varieties is 

 most popular. The Maryland Station 1 reports 25 per 

 cent, heavier yield from planting 30 x 14}^ inches than 

 from 36 x 12 inches. The average of Canadian" exper- 

 iments for the six years, 1896-1901, shows that 12 to 

 14 inches asunder in 3o-inch rows was better than 10, 

 1 6, or 1 8 inches, whether considered from the stand- 

 point of total yield or of total yield minus the seed. At 

 North Dakota Experiment Station, 3 with 4o-inchrows 

 and the variety Early Ohio, it was better to plant the 

 sets 10 inches asunder than at greater distances. 



Depth of Planting. The best depth varies to 

 some extent with the soil, climate, and season. It is 

 better to plant deeper on an open or light soil than on 

 a compact or clay soil, in order to insure a more uniform 

 temperature and moisture supply. These conditions 

 aid in the production of good quality tubers. In a 

 wet or a cold climate shallow planting may be good 

 practice. In a wet season, on a compact soil, i inch 

 or 2 inches deep seems to be best. The Michigan 

 Experiment Station* reports that on a sandy loam, in 

 1892, the yields of potatoes planted at various depths 

 were, per acre : 2 inches deep, 275 bushels ; 3 inches, 

 298 bushels ; 4 inches, 279 bushels ; 5 inches, 273 

 bushels; 6 inches, 238 bushels. At North Dakota Ex- 



1 Md. Bui. 31, p. 77. * Can. Exp. Farms Report, 1901, p. 117. 



3 N. D. Report, 1901, p. 96. * Mich. Bui. 95, p. 9. 



