THE MONTHLY Hl'lJ.ETIN. 235 



not of course vouch for what the future may show), there is no definite 

 correlation between tlie analysis of soil, chemical or mechanical, which 

 can be used as a reliable laboratory method for determining upon the 

 adaptability of a soil for a crop without doinj? more injury than good? 

 This idea, moreover, is not to be confused with the difference in pro- 

 ducing power of different soils for a given crop. That is due to other 

 factors which I have often considered with you, and whieh undoubtedly 

 you understand much better, namely, the supply of air and water and 

 available plant food and warmth in proper proportions. Thus, one soil 

 will produce three tons of alfalfa hay to the acre, another will ])roduce 

 six and still another will produce nine. There is nothing, however, to 

 show that the difference here is concerned with the difference in adapt- 

 ability of those .soils for crops, but merely that the inherent proiducing 

 powers vary between those soils. To emphasize this point we need but 

 consider the fact that many other crops, chosen for these three types of 

 soils, would in all probability, to judge from scientific data thus far 

 in hand, yield in the same proportion that the alfalfa did on those 

 same types of soil. It is true that there are a few crops — very small 

 in number so far as known — that prefer the lighter to the heavier 

 soils. But on the other hand that is but a minor matter compared 

 to the very large number of crops of all classes with which we have 

 to deal in practice, that are grown on all types of soils, and success- 

 fully, wherever the soil is managed so that the plants are enabled, 

 through that good management, to obtain their ample (juota of the great 

 essentials to their well being: air, water, heat, light and available 

 plant food. It is for that reason that climatic factors are much more 

 important determinants than soil type as to the adaptability of the 

 latter for crops, because the climatic conditions regulate the heat 

 and light supply, because they regulate the water supply, and becanse 

 indirectly through the water supply, they regulate the air and the 

 plant food supply. Climatic conditions begin to affect soils from their 

 very formation and origin, and continue to affect them throughout, 

 and very profoundly. That is the reason for their great importance 

 and the indis])ensable nature of a knowledge of climatic factors to 

 the determination of the kind of crop to grow on any soil. 



I trust that I have made emphatic enough the idea that for practical 

 purposes — and we are only considering such at the present time — 

 laboratory analysis in the correct sense of that term and examination 

 of soils are of minor value — and I might add of very minor value — 

 in the determination of what kind of crops to grow on those soils; 

 that the climatic factors, on the other hand, are of major value, and 

 absolutely indispensable to the consideration of the problem in ques- 

 tion. I trust that at least the publicity given to these statements will 

 do away with a great deal of some of the most widely current miscon- 

 ceptions with reference to the mission and functions of laboratory 

 analysis of soils. AVhatever such laboratory work with reference to 

 soils niay do it has, in my opinion, but very little or nothing through 

 analysis, mechanical or chemical, to do with determining the adapta- 

 bility of a given soil for a given crop. Most soils will produce most 

 crops which are suited to the climatic conditions surrounding tho.se 

 soils, and the extent of productiveness of any given soil for any given 



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