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found that a variety of the potatoe which bears seeds abundantly will 

 maintain its health and vigor for a much longer period if the blossoms 

 are annually destroyed, than if it is permitted to ripen its seeds each 

 year. 



Our next inquiry is, how and where the main crop should be planted — 

 what soils, situations, and modes of culture are best calculated to miti- 

 gate the effects of the disease ? Clays and heavy wet loams are known 

 to be least favorable to the growth of the potatoe, and in these soils the 

 disease seems to have been most virulent. But the evidence respecting 

 all soils is very contradictory, and the difference in the results observed, 

 was probably owing, in many instances, to a difference in situation, &c., 

 rather than to any peculiar property of the soil. 



That a given variety of potatoe may suffer more from the blight in one 

 situation than another, is what might have been expected, from the known 

 conditions which favor the growth and increase of parasitic fungi. 

 Many have observed that the disease was first developed, or proved most 

 destructive when potatoes were growing under precisely the same circum- 

 stances, which predispose wheat plants to the attack of mildew on damp, 

 low-laying soils, Avhere the air could not circulate freely. On land natu- 

 rally rich, or highly manured, on the sites of dunghills, or on portions 

 of fields where dung heaps had been laid, the plants have been very 

 much affected. Light loams, in rather elevated or open situations, should 

 therefore be selected for the potatoe crop, and much less than the usual 

 quantity of manure should be applied, if it would not be much more ad- 

 visable to manure the previous crop instead, where practicable. It is 

 probable the disease may be influenced, to some extent, by the nature of 

 the manure ; gross animal manures, when applied in quantity, are well 

 known to produce in plants a tendency to decay. On the other hand 

 partially decayed leaves, or charred vegetable matter, are highly favora- 

 ble to healthy vegetation. We may also, by other means, contribute to 

 the health of our plants. I have observed, in many instances, potatoes 

 have been grown in hills much too near each other. The climate of this 

 section of the country is somewhat peculiar. In the earlier part of sum- 

 mer, we have usually much dry sunny weather, during this period the 

 o-rowth of the plants is slow, much of the ground remains uncovered by 

 foliao-e and exposed to the sun ; a great amount of heat necessarily accu- 

 mulates in the soil. When rain falls, if the temperature continues high, 

 the combined influence of the warmth and moisture of the soil and air, 



