THE POTATO IN BRITISH COLUMBIA. 23 



Arrangements are being made for carrying on certified potato-seed work in 

 British Columbia. Tbe need is urgent if we are to keep out the more serious 

 potato-diseases, obtain pure seed), and regulate the various potato types. At the 

 present time this Province is practically free of such diseases as leaf-roll and mosaic, 

 which reduce the yield so greatly in many countries; therefore it is necessary to 

 take precautionary measures. 



The importation of potatoes from some countries has already been stopped 

 because of potato-wart, etc., and it behoves the growers to be prepared for further 

 restrictions. Not only this, if it is possible to grow more and better potatoes it 

 should be done. It will assure the growers higher yields and) higher prices. The 

 question is an important one not only for the large growers, but also for the grower 

 who produces potatoes in small quantities. 



At the time this bulletin goes to press it will be impossible to have the certified 

 seed standards ready for publication; however, it is our intention to later prepare 

 a circular on certified -seed production, and these standards will be included. 



The result of this work will make it possible for good, reliable British Columbia 

 seed-potatoes to be obtained within the Province for the benefit of the public of the 

 Province. 



Many of the seed-potatoes offered for sale in the spring of the year are only 

 the culls from taUe stock. The buyer has nothing else but potatoes which are too 

 small to peel, for planting. iSome of these small potatoes may come from high- 

 yH'lding, healthy plants, but the greater part come from small, w r eak, and diseased 

 plants. The result is " like begets like," and! it is not long before the stock runs out. 



Change of Seed. Whether or not it is advisable to change seed every so often 

 is a question which affords a great deal of discussion. The majority of potato- 

 growers believe a change is better ; personally, the writer believes that if a grower 

 selects his seed 1 carefully each year a change is unnecessary, provided climatic con- 

 ditions are favourable. In this respect it is interesting to quote the following experi- 

 ment carried on by Dr. C. A. Zavitz at Guelph Experimental Station, Ontario : Five 

 varieties of potatoes w r ere grown for twenty-six years in succession without any 

 introduction of tubers from an outside source. Care was taken each year to select, 

 from the crop which was produced, good seed-potatoes for planting in the following 

 spring. No hill selection took place in any year in connection with this experiment. 

 The fertility of the soil probably remained about uniform as in the four year's 

 rotation in which the potatoes were grown; three farm crops were removed from 

 the land ; barnyard manure was used once, and' no commercial fertilizer was applied 1 . 

 Starting with 1890, the average yield per acre per annum for the five varieties for 

 the five-year periods was as follows : 



Bushels. 



1890-94 : . . . 133.0 



1895-99 212.0 



1900-4 237.2 



1905-9 208.7 



1911-14 211.1 



The average for the whole period 1 of twenty-five years was 200.4 and for the last 

 five years 211.1 bushels per acre. The average yields for the second, fourth, and 

 fifth periods were comparatively close. The yield for the first period was low and 

 that for the third was high. 



The average yield per acre of the five varieties in 1915 was 30 bushels per acre 

 greater than that of 1890. The results show that potatoes have been grown on the 

 one farm for twenty-five years without change of seed, with a resulting increase in 

 production. When a satisfactory yield can be obtained with a certain variety for a 

 period of years, and that variety continues from that time to yield well, it would 

 seem undesirable for any one to change seed under such conditions. Every grower 

 should experiment for himself along this line. The so-called running-out of pota- 

 toes is due to poor selection, and therefore a change of seed in this case would be of 

 decided advantage. 



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