Truog's Test Best 



"I've been reading about the Truog Soil Acidity Test. They say 

 it's a little more complicated, but it's better than the litmus because 

 it tells how acid the soil is and gives one a better idea of the amount 

 of lime to use. I've been sending samples of my soil to the experi- 

 ment station to be tested for acidity. It gives me a little more con- 

 fidence in spending money for lime. 



"Do you know, it seems mighty queer that this soil about here 

 should be sour. This is a limestone country and a good many round 

 here don't need to buy lime. But it pays me to use two tons to the 

 acre, though nearly all my farm is underlaid with fine gravelly lime- 

 stone subsoil. The surface is sour. The experts say that rain, 

 with the aid of years of cultivation, has leached the lime out of the 

 top eight inches. This, together with the lime removed in crops 

 taken off the land has seriously reduced the supply. My experience 

 has really shown that. 



"I found that the first year after I had seeded alfalfa on my soil, 

 when I didn't use lime the alfalfa never grew well. It was thick 

 enough, but it always looked yellowish and I never got a very good 

 first or second crop. 



The next year it would make a surprisingly healthy green and 

 rapid growth. 



Limestone Soils May Need Lime 



"It gradually dawned upon me that the improvement was due to 

 the fact that the roots in the early life of the crop were drawing their 

 nutriment from the surface soil, in which lime was lacking. Later, 

 when the roots were more widely established in the subsoil, the 

 plants could get all the lime they wanted and they made thrifty 

 growth. I know of a good many farmers who say that their stands 

 and yields of alfalfa improve with age for the first two or three years. 

 Others say just the opposite. I believe the lime content of the sub- 

 soil has something to do with it." 



This is undoubtedly true. If the surface soil is sour and the sub- 

 soil has abundant lime alfalfa will improve rapidly as the roots be- 

 come established. If both surface soil and subsoil are sour the al- 

 falfa will rapidly deteriorate with age or will fail at the outset. The 

 surface soil may be neutral and the subsoil sour if the land has been 

 cropped heavily, taking much of the lime out of the subsoil and put- 

 ting it into the surface soil as the manure is returned. Such a con- 

 dition does not prevent successful alfalfa production. I have ob- 

 served many excellent fields growing under these very conditions. 



The principal point to consider is to have the surface eight inches 

 or more well supplied with lime. It is here that the alfalfa bacteria 

 and the alfalfa roots are most abundant and active, and it is here 

 that they need lime to make conditions favorable. 



The Kind to Buy 



What kind of lime shall be used? When is the best time to apply 

 it? How shall it be done? These are very common inquiries. 



Ground limestone, marl, air-slaked lime, lime refuse from sugar- 

 beet factories or lime kilns, and fresh lime are all good, if bought 

 right and used right. Generally freight is the most costly item in 

 buying agricultural lime. Particularly because of this reason, it is 



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