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}iave a forcing effect on the potatoe plant, which causes the haulm to grow 

 "with excessive luxuriance, so that the foliage of the plants of one hill, 

 soon interfere with that of another. Whenever this happens, the plants, 

 instead of quietly attending to the formation of tubers, become engaged 

 in a struggle with each other, fighting, as it were, for the precious light. 

 The invariable result is, that all are more or less injured ; these stems are 

 drawn up, the sap has further to travel in its ascent and descent ; many 

 of the lower leaves become shaded, and, therefore, useless ; the stems are 

 also more brittle and liable to be laid, and the produce of plants so situ- 

 ated, whether they be potatoes or forest trees, will, invariably, be found 

 deficient, as compared with crops grown at proper distance apart, and 

 owing to the want of a free circulation of air around them, and the 

 unhealthy condition, induced, they become a more easy prey to the 

 parasite. 



When I Avas a boy, I had observed that potatoe plants, with stout stems, 

 had invariably the finest tubers, so, when walking round the garden 

 with my grandfather, and seeing a plat of potatoes, with stems as tall as 

 myself, I ventured to congratulate him on the large crop he was likely 

 to obtain, when he puzzled me considerably by saying, that I was much 

 mistaken, for they were all running to tops. How in the world the pota- 

 toes could run into the tops, I could not imagine ; many a time since, 

 I have heard this remark, and possibly there may be some now, who 

 would be as much puzzled to account for it, as I was then. The expla- 

 nation is this : The matter which constitutes the tubers of the potatoe, the 

 roots of carrots and turnips, the seeds of grain, the fruit of our orchards, 

 and the wood of trees, is elaborated or prepared in leaves, by the action 

 of light. The fluid absorbed from soil by roots, ascends through the 

 woody part of the stem, circulates through the upper surface of the leaves 

 where it undergoes certain chemical changes, and then descends by the 

 bark; and it is considered that the mature leaves only, and of those, 

 such only as are not shaded by others, are efficient ; hence the deficiency 

 in produce, when the leaves of one plant shade those of another ; and of 

 the indifferent crop of tubers, compared with the growth of the stems, 

 when the plants are so crowded, as to be drawn up, their stems laid pros- 

 trate, and much of the foliage rendered useless. 



There are two or three other questions rel iting to the culture of the 

 potatoe on which I may venture a few remarks, viz : What is the best 

 mode of applyinging mannre to the potatoe ? Is it advantageous to 



