20 



Potato Growing. 



[APRIL, 



early in spring as possible, before sprouting has commenced, so 

 that the damage which sprouted potatoes suffer in course of 

 bagging and transit may be avoided. 



Scotch Seed. — That Scotland affords a good change of seed 

 for England is undoubted, but why this should be so is not quite 

 clear. A number of influences are probably at work. The 

 growth of potatoes in many parts of Scotland is frequently 

 interrupted by autumn frosts, and the crops are lifted before 

 they are as well matured as the crops in many parts of England. 

 Now if the foliage of potatoes is damaged by frost or some other 

 influence before the tubers have attained their full size, there 

 will be fewer big potatoes in the produce, and, conse- 

 quently, a better selection of seed will be possible. In other 

 words, a farmer will be using for seed a certain proportion of 

 tubers which, had they had time to reach their maximum growth, 

 would have passed to the market as ware or saleable stuff. It 

 is possible that a big potato has more " constitution " than a 

 small one, and, consequently, a small potato not yet arrived at 

 its full growth — in brief, immaiure — may contain more innate 

 vigour than a small yet fully mature potato that may have been 

 the produce of a weakling. Granting, then, that the proportion 

 of ware is greater in English- than in Scotch-grown crops, it is 

 only reasonable to suppose that the proportion of stunted weak- 

 ling tubers is the greater in the English-grown seed. Moreover^ 

 the proportion of such tubers will tend to increase from year to 

 year, since the practice of retaining for seed small potatoes 

 insures that practically the entire produce of weakly plants 

 falls into the " seconds " or seed -size class. 



This may to some extent explain why in England it becomes 

 necessary to change the seed so frequently and why Scotch seed 

 does so well in England. There is yet another point, however. 

 In spring the Scotch seed is slower in sprouting than the 

 English, and therefore runs less risk of damage. 



Immaiure Seed — To throw further light on this point a test 

 of immature seed was made in 1905, seed of a number of 

 varieties was lifted in 1904 (i), in immature and (2) in mature 

 condition. To obtain seed in an immature state small - 

 quantities of a number of varieties were lifted whilst the 

 tops were still green and the skins of the tubers tender. 



