12 



leguminous plants of the clover and cowpea varieties, furnish another method 

 of enrichment highly desirable on almost all the soil types of St. Mary County. 

 and does not present the difficulties of liming, since this kind of fertilizer is of 

 great benefit to the tobacco crop. These leguminous crops furnish a fair forage 

 for cattle during a period of. their growth, and if allowed to continue growing 

 they produce a mass of organic matter for incorporation with the soil : and all 

 the time, beneath the surface of the ground, certain minute bacteria, living on 

 the roots, are taking nitrogen from the air and storing it in the soil, thus helping 

 in the enrichment of the soil. * * * 



For certain crops special fertilizers will always be necessary, and commercial 

 fertilizers are to be commended highly, but in St. Mary County on all soils the 

 use of stable manure and the plowing under of green crops are to be preferred, 

 while on the soils least suited to tobacco the abandonment of that crop and the 

 free use of lime in conjunction with organic matter have already become neces- 

 sary, as is shown by the forest areas given over to nature's cultivation. 



During the same year Bonsteel also surveyed and mapped the 

 soils of Calvert County, Md., and in his report, "A Soil Survey of 

 Calvert County, Md.," in discussing the Leonardtown loam, he makes 

 the following statement : 



The uniformly yellow appearance of the surface soil indicates a lack of 

 organic matter, which should be supplied in the form of stable manures and by 

 plowing under green crops, like crimson clover and cowpeas. Such a treatment 

 would not only increase the actual supply of plant food, but would also improve 

 the texture of the soil. Unless it is absolutely necessary that tobacco should 

 be raised upon areas of this type, the application of lime should be tried in 

 connection with stable manures and green fertilizers. The fact that tobacco is 

 not largely raised on this soil should make this line of improvement much 

 easier than on other types of soil to which tobacco is one of the crops best 

 adapted. 



The following year, 1901, this same type of soil was encountered in 

 making a survey of Prince George Count} 7 , Md., and in his report 

 upon that area Bonsteel states: 



This soil is only producing to its full capacity in the northern part of Prince 

 George County, where, through the use of green manures and lime, from 15 to 

 18 bushels of wheat per acre are frequently raised upon it. Elsewhere this 

 soil, type is generally lacking in organic matter. The Leonardtown loam should 

 furnish an excellent soil upon which to introduce stock raising and dairying at 

 points where market gardening can not be undertaken. 



While Bonsteel has repeatedly recommended the use of green i 

 manure and lime, it would seem from this last statement that he had 

 not previously found the farmers actually putting its use into prac- ! 

 tice. In the same report, under the heading of "Agricultural condi- ] 

 tions," he makes the following statement : 



Upon those farms where tobacco is raised lime is little used, since its appli- 

 cation injures the burning quality of the leaf. Commercial fertilizers, however, j 

 have been used in large quantities for many years to increase the production ; 

 of tobacco and the grain crops. They have been considered a complete fertilizer j 

 in many cases, and too little attention has been paid to the restoration of j 

 organic matter to the soil. Recently leguminous crops in the form of cowpeus j 

 and crimson clover have beeji introduced and the system of agriculture improved 

 through this means. The production of good forage crops can only be resumed 

 by a more generous use of lime and the leguminous green manures. The cow- 

 pea seems better adapted to this end than any other leguminous crop. 



In 1903 Taylor and others were sent to St. Mary County and d-c- 

 where to investigate the relation between the chemical constituents 



