110 EXPERIMENT STATION RECORD. 



was decidedly detrimental and for a time delayed the development of 

 agriculture. By chemical analysis fully as much lime was found in 

 imuiy soils as phosphoric acid, potash, and other plant nutrients, and the 

 conclusion was reached that manuring with lime was no more necessary 

 than manuring with other ingredients. This conclusion was far from 

 correct, and it was found in the course of time that the lime cpiestion 

 was for the larger part of the soils of Germany the all-important one, 

 inasmuch as lime is not only an essential plant nutrient, but is also of 

 the greatest importance in connection with the physical properties and 

 the changes taking place in the soil. As an instance of this it may be 

 mentioned that the system of potash manuring tested in Germany by 

 Schultz-Lupitz first showed superior results when the potash manur- 

 ing in sandy and heavy soils was accompanied by a sufficient applica- 

 tion of lime. Most of the directions for fertilizing soils which did not 

 actually show a large excess of lime became fully effective only when 

 the soil was given a iiood dressing of lime. The promotion of our 

 knowledge in regard to lime is at present one of the most important 

 problems before the agricultural experiment stations, and has been 

 taken up on a large scale in Germany. Fortunately the poverty of a 

 soil in lime can be determined with accuracy by chemical analysis and 

 by determining the different forms in which the lime is present. 



Although in some respects soil analysis leaves much to be desired, it 

 is reliable in studying the lime question, so that it is only necessary to 

 make an examination of a soil to determine whether or not it is defi- 

 cient in lime. To this end most of the agricultural experiment stations 

 have already made extensive investigations on the lime content of 

 soils, and where a deficiency in lime has been found the region has been 

 searched for deposits of lime and marl to correct this deficiency. The 

 results which have followed this line of station work in most parts of 

 Germany have been of the highest value. 



For other purposes soil analysis is comparatively seldom required of 

 the stations. For ascertaining the nitrogen requirements of the soil, 

 for instance, soil analysis is almost never resorted to, for it is known 

 that with the exception of certain peaty soils all cultivated agricultural 

 soils in Germany show a pronounced deficiency in nitrogen, so that the 

 use of nitrogenous fertilizers in Germany is very general. 



A more important question which, however, has not yet been solved, 

 is the determination of the need of soils for phosphoric acid. Simple 

 chemical analysis is for this purpose almost useless, although when only 

 a trace of phosphoric acid is found in a soil it is of course very evident 

 that the sod needs phosphoric acid. But when chemical analysis shows 

 the soil to be rich in phosphoric acid it is by no means certain that the 

 soil may not need phosphoric acid badly. The phosphoric acid in such 

 a soil may be in very insoluble form, and so render heavy manuring 

 with phosphoric acid necessary. This feeling of uncertainty as to the 

 requirements of the soil for phosphoric acid leads farmers to apply an 

 excess of phosphoric acid in order to be on the safe side. Consequently 



