184 



POTATO CULTURE 



They pointed out a particular variety of which the best yield had 

 been as much as forty-seven tons per acre. Of course, that is not a 

 thing they are doing all the time. 



The point I want to leave with you is this — that they have gone 

 way beyond w^here we have gone in developing varieties that are 

 adapted to their conditions. Their particular varieties, we find, 

 when grown over here, don't do so well. Under irrigation in Colo- 

 rado, they are doing very well indeed. 



Why do we see such results, and why do we get such results in 

 our own country? Is it farming? I conclude it is not. While 

 average farming there is much above ours, yet we have some farmers 

 just as skilful as some there. Is it soil? While the average soil 

 where they grow potatoes is better suited to the crop, because they 

 have learned better than to plant potatoes on land not adapted to 

 potatoes, nevertheless we have some soils, probably, just as well 

 adapted to potatoes as any they have. I do not believe those are 

 the two factors that dominate the question. 



What is the factor? I believe that in a much larger degree than 

 we have yet seen, climate is responsible for the great difference 

 we see in this matter of potato growing. Of course, climate is a 

 factor beyond our control in great measure. The potato requires, 

 first of all, what, from our point of view, would be cool summer 

 climate. The one factor that is working against potato growing 

 in New York State is that almost every year we have a period of 

 very hot weather during the growing season. Whenever during the 

 growing season the temperature goes above ninety degrees, the 

 potato crop is being diminished very rapidly. That is one of the 

 reasons why in Great Britain and in Germany they can grow crops 

 way beyond what we have arrived at yet. I have a little data to 

 substantiate this. I discussed the matter with Dr. Wilson of the 

 United States Weather Bureau, and asked if he could get data. It 

 is not so much the average temperature, but the temperature of 

 the hottest ten days of July, for instance, that affect the potato 

 crop. I have here such data as Dr. Wilson furnished on this subject: 



Scotland Orono, Maine 



Mean tern- Precipi- Mean tem- Mean Precipi- 



perature tation perature maximum tation 



June 55° 2-3 June 61.9° 72° 3.43 



July 58° 3-4 July 66.9° 78° 3.22 



August 58° 3-4 August 65. ° 76° 3.50 



