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the wheat will be better than when mown once : now this, at 

 first sight, certainly appears contrary to all theory, for the 

 food consumed on the soil during pasturing would again be 

 restored to the soil in the liquid and solid excretions ; none 

 of the elements useful to the growth of plants would be lost, 

 while in mowing the clover the whole of these elements are 

 removed; hence we should certainly expect a larger crop 

 where the elements had been left ; but such is not the fact. 

 Admitting that all these elements, which are secreted by 

 the cattle, be washed away by winter drainage, which will 

 probably be the case, we have not even then an explanation 

 of this curious fact. Knowing there must be some cause for 

 it, I commenced an examination of the roots of clover in 

 these circumstances, and from many sources I have ascertain- 

 ed that the weight of root in clover pieces mown twice, bears 

 a proportion to those in pastures of three to one. 



I have also ascertained that the weight of roots contained 

 in an acre of good mown hay is about 3,630 lbs. (calculated 

 dry), while the weight of roots from a portion of the same 

 field, which had been pastured, gave only 1,440 lbs.; hence 

 we have at once an explanation of the cause of success in 

 one case and failure in the other ; for these roots, during their 

 decay in summer, furnish materials valuable for the growth 

 of wheat — the carbonic acid which they give off acts power- 

 fully on the silicates in the soil and promotes their solution, 

 while the nitrogen which they yield, which in the mown por- 

 tion amounts to 54 lbs. per acre, furnishes that important 

 element to its growth. These decompositions, of course, will 

 go on with three times the vigour where there is three times 

 the weight of root ; hence the cause of this curious phenom- 

 enon is no longer a mystery. 



I believe I have now taken every subject into consideration 

 with regard to the failure of the red clover crop on the sand 

 lands generally, as well as the probable means of preventing 



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