PLANTING 93 



loam. This would result from rows 30 inches apart 

 with plants 12 inches asunder. In the United King- 

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

 1 2 to 15 inches asunder for late varieties and 8 to 1 2 

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

 most popular. The Mar^^land Station' reports 25 per 

 cent, heavier yield from planting 30 x 14)2 inches than 

 from 36 X 1 2 inches. The average of Canadian' exper- 

 iments for the six years, 1 896- 1 901, shows that 12 to 

 14 inches asunder in 30-inch rows was better than 10, 

 16, or 18 inches, whether considered from the stand- 

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

 North Dakota Experiment Station,' with 40-inch rows 

 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 produdlion of good quality tubers. In a 

 wet or a cold climate shallow planting may be good 

 practice. In a wet season, on a compadl 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- 



• Md. Bui. 31, p. 77. ' Can. Exp. Farms Report, 1901, p. 117. 



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



