15 'Nov., 1919.] Change of Seed of Potatoes. 653 



to degenerate. It is a frequent thing to hear large buyers or 

 starch manufacturers (Gerard writes of European conditions) declare 

 that, after having imported and placed at the disposal of growers, 

 varieties of potatoes noted for their large crops, they have seen them 

 give excellent results the first year, fall away the second year, and give 

 results even lower than native potatoes in the third year. This is 

 indeed true, hut by no means inexplicable; the degeneration which one 

 sees in this circumstance does not result from the natural weakening 

 of the variety; it simply results from the entire lack of care with 

 which the plants to be perpetuated are chosen. All the good tubers 

 are sold to the market, and it is from the inferior, discarded tubers, 

 that has been demanded a continuation of the qualities they cannot give. 

 I have demonstrated practically, and have established the fact that if 

 suitable tubers are selected for planting, and the cultivation accom- 

 plished with the needed care, the quality and the quantity of the crops 

 will be maintained under all satisfactory conditions." 



Here we have a strong note against change of seed, with some logical 

 backing, which in the case of the advocates of change is always lacking. 



These quotations show that amongst those who have written on this 

 question there is much difference of opinion as to the necessity or other- 

 wise of changing seed. 



The opinions of the advocates of change of seed appear to be based 

 on a belief in the inevitable senility of plant life, but they do not 

 produce any evidence to support this theory, which is not capable of 

 rational explanation. 



Further they seem to ignore the fact that cultivated crops, i.e., plants 

 of high economic value, are cultivated under what are practically arti- 

 ficial conditions. That being so, it is only reasonable to understand that^ 

 when the high standard of those artificial conditions demanded for the 

 maximum results are not maintained, owing to, say, bad farming, neglect, 

 or climatic cause, deterioration of the particular species under cultiva- 

 tion must follow. 



Conditions do obtain whereby a change of seed is justified. Several 

 of such conditions are cited herewith : — 

 The seed may be non-productive. 



It may be unsuitable for the soil in which it is grown. 

 It may be of a variety not desired by the buyers in the place where 



it is marketed. 

 It may be comprised of so many varieties as to render it useless 



for sale for seed purposes. 

 The crop may be grown in a climate so warm as would make it 

 impossible, without facilities for cool storage, to carry seed 

 over from season to season in good condition. 

 It will be noted that, with the exception of the last-mentioned cir- 

 cumstance, all other reasons for changing seed are within the control 

 of the growers. Their control lies in the amount of care expended on 

 the selection of suitable seed, and its storage. 



My own opinion is that, given seed of a fair to good standard of 

 prolificacy, and a district suited to the cultivation of the potato, there 

 is no reason why a grower should ever have to import new seed stock. 

 Change of seed is made, firstly and lastly, to secure better returns. The 

 one reason why any parcel of seed gives better returns under the same 



