368 THE POTATO 



right time gave heavy tonnage and indicated what 

 was to be. It became plain that regulated supply 

 of water must be served; that in this district late 

 potatoes must be held back to make their tuber 

 growth during cool weather. 



"Even though the first reservoirs of magnitude 

 were completed by the farmers at a time to in- 

 crease production which found a light demand 

 during the panic period of 1893 yet the results 

 were so satisfactory that the building of reser- 

 voirs has been continued ever since. Except in 

 those districts where potatoes can be allowed to 

 mature during the heat of the summer, or in those 

 rare instances where the river supply is continu- 

 ous, reservoirs are a necessity. Once potatoes 

 have set on they must be kept moist so their 

 growth be continuous. If arrested growth takes 

 place and they are then watered the further de- 

 velopment will be in the form of knobs that make 

 rough potatoes. 



"Those who believe that potatoes must have an 

 exactly suitable soil for successful culture should 

 visit the Greeley district. Not only do the soils 

 vary from heavy clay or adobe to sand, which 

 need entirely different handling, but also the same 

 fields that have raised potatoes for forty years in 

 rotation with other crops are now handled in other 

 ways than were formerly expedient. A rising 

 water table due to pressure from irrigated lands 

 at higher levels has necessitated more aeration by 

 thorough cultivation of the soil. 



"Had we been told twenty years ago what was 

 needed to raise good potatoes brains and hard 

 work we likely would have quit right there, but 

 we gradually grew into it and perfected the sys- 

 tem which can best be studied in all its varieties 



