THE RATIONAL USE OF L 



Wm. p. Brooks. 



No subject connected with the various steps which may be 

 taken to increase the productive capacity of soils interests our 

 farmers at the present time more than the use of lime. The 

 practice of applying lime, while it has always been somewhat in 

 vogue, has become much more general during the past few years 

 than formerly. This change must on the whole be regarded with 

 favor; but there is a possible danger that the pendulum may 

 swing too far in the other direction. It is well to remember that 

 in most parts of the state there is sufficient lime in the soil to meet 

 the direct requirements of our growing crops. This does not mean 

 that lime is not often highly useful; but is mentioned simply to 

 emphasize the fact that if useful it is usually because of indirect 

 or secondary effects and not because more lime as a source of food 

 for the growing crop is required. The facts being as stated, it is 

 highly iinportant to know what these indirect or secondary ef- 

 fects may be. 



POSSIBLE EFFECTS OF LIMING. 



The secondary or indirect results which will follow an applica- 

 tion of lime must of course vary with soil conditions, but the 

 principal possible effects which are of importance are as follows : 



1 . Free acid if present is neutralized. A sour soil is sweetened. 



2. Some of the less soluble potash compounds of the soil are 

 rendered available and the need of potash manures will be lessened 

 at least for a time. Liming will not permanently take the place 

 of potash manuring, for it will be understood that it adds no 

 potash to the soil. It simply makes it possible to draw upon the 

 stock found in the soil more rapidly, and this, if persisted in with- 

 out application of potash, will ultimately result in the exhaustion 

 of this element. 



3. Phosphatic fertilizers are often rendered more effective. 

 This seems to be especially true of the less soluble materials, 

 such ao fine ground rock phosphates. An application of lime 

 appears also to increase the availability of the comparatively 

 inert phosphates of the soil itself. 



4. Organic matter decomposes more rapidly and the plant 

 food it contains becomes more promptly available. This action 

 is most important in its relation to nitrogen, and it is especially 

 valuable in heavy soils, in which organic matter naturally decays 

 slowly. Its effect is also often important after turning under a 

 green crop. On the other hand rapid decomposition of the or- 



