EXPERIMENTS OX CLOVER-SOILS. 163 



per acre ! The truth of the matter seems to be, that the part of the 

 field on which the clover was allowed to go to seed, was naturally 

 much richer than the other part, and consequently produced a 

 greater growth of clover and clover-roots." 



We can not find anything in these experiments tending to show 

 that we can make land rich by growing clover and selling the crop. 

 The analyses of the soil show that in the first eighteen inches of the 

 surface-soil, there was 6,550 Ibs. of nitrogen per acre, on one part 

 of the field, and 10,300 Ibs. on the other part. The clover did not 

 create this nitrogen, or bring it from the atmosphere. The wheat 

 with which the clover was seeded down, yielded 40 bushels per 

 acre. If the field had been sown to wheat again, it probably would 

 not have yielded over 25 bushels per acre and that for want of 

 available nitrogen. And yet the clover got nitrogen enough for 

 over four tons of clover-hay ; or as much nitrogen as a crop of 

 wheat of 125 bushels per acre, and 7| tons of straw would remove 

 from the land. 



Now what does this prove ? There was, in 18 inches of the soil 

 on the poorest part of the field, 6,550 Ibs. of nitrogen per acre. A 

 crop of wheat of 50 bushels per acre, and twice that weight of 

 straw, would require about 92 Ibs. of nitrogen. But the wheat can 

 not get this amount from the soil, while the clover can get double 

 the quantity. And the only explantion I can give, is, that the clover- 

 roots can take up nitrogen from a weaker solution in the soil than 

 wheat-roots can. 



" These experiments of Dr. Yoelcker," said I, " give me great en- 

 couragement. Here is a soil, * originally rather unproductive, but 

 much improved by deep culture ; by being smashed up into rough 

 clods early in autumn, and by being exposed in this state to the 

 crumbling effects of the air.' It now produces 40 bushels of wheat 

 per acre, and part of the field yielded three tons of clover-hay, 

 per acre, the first cutting, and 5J- bushels of clover-seed after- 

 wardsand that in a very unfavorable season for clover-seed." 



You will find that the farmers in England do not expect to make 

 their land rich, by growing clover and selling the produce. After 

 they have got their land rich, by good cultivation, and the liberal 

 use of animal and artificial manures, they may expect a good crop 

 of wheat from the roots of the clover. But they take good care to 

 feed out the clover itself on the farm, in connection with turnips 

 and oil-cake, and thus make rich manure. 



