256 



The World's Commercial Products 



plant will not withstand frost, and the early kinds should be afforded some protection if late 

 frost occurs after the shoots are above the soil. 



The ground should be kept free of weeds, and when the shoots are about six inches high 

 soil should be drawn up around them. The potato tuber is really a thickened underground 

 stem borne at the ends of runners which originate in the axils of the lower stem leaves. By 

 earthing up the stems the production of these is promoted and a heavier crop results. 



In 1845 a devastating disease made its appearance amongst potatoes in this country and 



threatened the entire destruction of 

 the crop. This disease proved to 

 be due to a Fungus {Phytophthora 

 infestans), which first attacks the 

 leaves, causing discoloration, and 

 thence rapidly spreads down the 

 stems to the tubers. Whilst no 

 actual cure is at present known, 

 spraying the crops at intervals with 

 a solution of copper sulphate and 

 lime (Bordeaux mixture) will check 

 the disease if not actually destroy- 

 ing it. Some varieties of potatoes 

 are capable of resisting disease to a 

 very considerable extent until they 

 become degenerate. A disease-proof 

 potato is a desideratum which plant 

 breeders are endeavouring to fill. At 

 present there is no such a thing 

 absolutely, any more than there is a 

 disease-proof wheat, dog, horse, or 

 man. By a continual change of 

 stock, care to plant only the best 

 varieties, and judicious spraying, the 

 disease can be kept in check if not 

 in abeyance. 



The cultivation of the potato is 

 now carried on in practically every 

 part of the world — from Iceland to 

 New Zealand, in Africa and distant 

 China. In this latter country it was 

 introduced by Roman Catholic 

 missionaries some thirty years ago, 

 and though despised by the rice- 

 eating Chinese of the south, the 

 potato has become a staple food of 

 the peasants in the more mountainous parts of the Empire. 



In Great Britain and Ireland the potato is one of the most important crops. In 1905 no 

 fewer than 1,225,228 acres were planted with potatoes. 



Lincolnshire, Yorkshire and Lancashire are the chief potato growing counties in England, 

 followed by Cambridgeshire and Cheshire. Fifeshire, Forfarshire, and Perthshire are the 

 principal Scotch counties. In 1905 the total yield for Great Britain and Ireland was 

 7,185,745 tons — the average yield per acre for the last ten years being 4'84 tons. 



In the same year Great Britain imported 3,664,290 cwt. of potatoes valued at £1,404,607. 



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By permission of Messrs. Sutton & Sons, Reading 



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