42 BOARD OF AGRICULTURE. 



rationally." Phosphoric acid is very little diflfusible in the 

 soil. If you apply it to the surface-soil, and pour water upon 

 it, it will pass down only a very short distance before it 

 becomes fixed, and the roots have to approach the surftice to 

 come in contact with it. To apply phosphoric acid rightly, 

 it should be put in deep, — ploughed in three, four, five or six 

 inches deep. The potash, being more diffusible, might be 

 spread nearer the surface. The nitrogen, in whatever form 

 you apply it, being rather diffusible, should be applied upon 

 the surface. In that way, we have taken the best precautions 

 for giving our crop its food during the period of growth. 



Now, having planted our corn upon a chemically fertilized 

 field, the only question with the crop is to have these chemi- 

 cals in contact with the roots during the whole period of 

 growth. There can be no question, if there is enough fertil- 

 ity in the land, if that fertility is in a soluble form, and if the 

 roots come properly in contact with that fertility, that the 

 result will be a good crop. But what is the fact about roots? 

 The roots occupy but a comparatively small area of soil. They 

 feed from the extremities. They pick up their nutriment 

 through the rootlets which are upon the small fibrous roots. 

 Plants differ in the depth to which their roots penetrate. 

 You can dig down into the soil where corn is growing, and 

 you will be able to trace the corn-root down as far as you can 

 ordinarily go. In one experiment as to the depth of roots, 

 I found, upon land which had not been manured for fifteen 

 years certainly, and probably for a longer period, and which 

 yielded about one-third of a ton of hay to the acre, the 

 grass-roots extended down twenty-five inches. These differ- 

 ent roots extend to different depths, and they have different 

 habits of growth, and the nature of the soil stimulates the 

 growth of these roots to a different extent, according to the 

 different kinds of plants. But confining myself to the corn- 

 plant, I will state that the corn-roots extend laterally as well 

 as downward ; that they cover the whole space upon which 

 they grow with immense rapidity. It is hardly conceivable 

 how fast the roots of the corn-plant are formed ; but they 

 extend out laterally. Starting from the plant, they put out 

 a few fibres throughout their length, and in a short time the 

 tough coating of all the roots is incapable of taking up any 



