l8 THE POTATO 



6. Light soils usually produce potatoes of better qual- 



ity, because they tend to shorten the growing 

 period by cutting off the moisture supply, and thus 

 forcing the potatoes to mature earlier; 



7, Those grown on well- drained sandy loam soils usu- 



ally keep better than those grown on stiff clay 



soils. ' 

 Aroostock County, Maine, is famous for its potatoes.' 

 Its soil presents a gently rolling surface, and is com- 

 posed essentially of drift deposited during the melting 

 of the ice after the ice age, and resting on a stratum 

 of limestone, which in many places comes to the sur- 

 face. The soil partakes of the general nature of drift 

 containing a considerable portion of sand and the usual 

 amount of organic matter. It is peculiarly suited to 

 potatoes, because it does not pack after hard rains nor 

 during periods of drouth. Its open and porous nature 

 permits the free development of tubers and the ramifi- 

 cation of the roots. The soil was originally covered 

 with a growth of hard and soft woods, consisting chiefly 

 of maple, cedar, birch, white poplar, spruce, hemlock, 

 and pine. The forest growth was dense, and in clear- 

 ing large quantities of ashes were produced, which 

 fitted the virgin fields particularly for the produ(5lion 

 of large crops of potatoes. After a few years of culti- 

 vation, the crop-producing power of the soil showed a 

 diminution, and to-day applications of farm manures 

 and commercial fertilizers containing a large percent- 

 age of potash are resorted to. Analyses of Maine soils 

 show that they are silicious, contain considerable or- 



» U. S. D. A., Div. of Chemistry, Bui. 5S, p. 5-8. 



