USE AND MISUSE OF LIME 249 



that it is unnecessary to lime an acid soil underlaid by limestone, 

 because the plant roots would quickly penetrate deep enough to 

 feed on the carbonate of lime. Numerous experiments show clearly 

 that when an acid soil is limed and the material thoroughly incor- 

 porated in the surface five to eight inches, aKalfa can be grown 

 most successfully^ and if not limed, failure results, regardless of 

 the facts that the acid soil may be underlaid at depths of two feet 

 or more by partially decomposed limestone, and thorough inocu- 

 lation made (Fig. 149) . 



Alfalfa Can Grow Well on Rich Acid Soils. — In some sections 

 it is not rare to see most excellent crops of alfalfa growing on quite 

 acid soils without liming and inoculation. These are either 

 tobacco fields which have been heavily manured annually for 

 several years, or rich and well-drained new lands. In either case 

 the alfalfa feeds on the soil as corn does, for example — being able 

 to secure its requirements without liming and without the aid of 

 nitrogen-fixing, nodule organisms. In some of these fields the 

 alfalfa roots were fairly well supplied with nodules, though not 

 nearly so well as compared with alfalfa growing in normal non- 

 acid soils. 



Usually, however, it is profitable to lime even these soils as 

 weU as those only slightly acid when growing alfalfa. It has also 

 been found that the richer the soil the higher the degree of acidity 

 alfalfa can tolerate. 



Not Necessary to Neutralize All Acidity at Once. — ^Some soils 

 are so strongly acid that it would be prohibitive to apply sufficient 

 lime to neutralize at once all the acidity in the surface six or eight 

 inches. For most general farm crops it is not necessary. In such 

 cases, a three-ton or four-ton initial application of pulverized 

 limestone, for example, may be sufficient to give desirable results 

 (Fig. 149). 



Use and Misuse of Lime. — ^The use of lime in agriculture is 

 perhaps one of the most striking illustrations of the tendency on 

 the part of the farmer to seek some panacea, or cure-all, for soil 

 ailments. Its use in farming dates back to 1100 B.C., and earlier. 

 History shows that in some places hming has been encouraged and 

 again discouraged, doubtless because of its misuse. The two 

 following quotations are good illustrations: 



'^Now that this lime [meaning lump or quicklime] is of 

 excellent use, and wonderful profit, do but behold almost all the 

 Countries of the Kingdom where there is any barrenness, and you 



