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diminlslied tlie amount of stems and leaves — an operation that may 

 have occasioned a great change in its constitutional condition. The 

 energies of the plant are withdrawn from its own nutrition and deter- 

 mined towards the production of fruit to such a degree, as to cause 

 its debilitation and decay — an effect with which we arc familiar in 

 fruit trees. In a temperate, mountainous country, it probably con- 

 tinues to live in high health. But it has been transported to every 

 variety of climate and of soil, and excessively, and, of course, un- 

 naturally, stimulated for the sake of large crops. ^Ve know the 

 effects produced on some other plants by a similar course. If a 

 pear tree is over-stimulated, the new wood will not ripen. If wheat 

 is over-stimulated by animal manure, the stalk is rank, tender, liable 

 to rust, and bears no fruit, or very little. Some garden vegetables 

 so treated disappoint our hopes altogether. Why may not similarly 

 unfavorable results occur in potatoes, by pursuing a course of treat- 

 ment so foreign from that which nature observes ? — Why are 

 potalo-plants grown on a good but unmanured soil, less liable to rot 

 than others ? Because, in this respect, they are situated more like 

 the wild plant. Excessive stimulation by manure increases the 

 amount of cellular texture, and makes the tuber softer and more 

 spongy, — and hence more subject to decay; more likely to be 

 affected by unfavorable atmospheric conditions. And when this 

 course of unnatural treatment is continued for two centuries, it is not 

 strange that, although the amount of yield is increased, it may be 

 done by undermining the health, and perhaps diminishing the vitality 

 of the plant. Probably Nature has Hmits beyond which her perversion 

 cannot be carried with impunity. 



Besides, in its wild state, the potato propagates itself by seeds as 

 well as by tubers. From recently grown seeds, it annually renews 

 its youth and health. And wild plants, which re-produce themselves 

 without human aid, resist tendencies to disease better than cultivated 

 ones. But we have checked the potato in its habit of re-production 

 from seed, because we wanted an increased yield of tubers — a result 

 attainable, in part, by preventing the plant from following out its 

 natural tendency to produce seed. We gain in one direction, and 

 lose in another. 



It has often been suggested, that we might perhaps recruit the 

 failing health of the potato, by raising it from seed ; and experience 

 teaches us, that potatoes so raised are usually best for the table. 

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