BUREAU OF SOILS. 485 



important soil problems presented in field, farm, or region. The in- 

 vestigations included such prominent soil problems as those presented 

 b,y the Volusia series of soils in NeAv York and neighboring States 

 and the peat lands on the Atlantic plains, as well as other unpro- 

 ductive lands in Maryland, Connecticut, Massachusetts, Pennsylvania, 

 New Jersey, Kentucky, West Virginia, Alabama, North Carolina, and 

 elsewhere. 



Volusia soils have been studied in relation to the most responsive 

 fertilizer combination and the eifect of liming. The organic matter 

 of these soils has received especial attention and the organic nitrogen 

 and phosphorus forms have been determined. These have an impor- 

 tant bearing upon the availability of these essential constituents. 

 It has been found that the nitrogen and phosphorus are tied up in 

 these soils in very resistant forms as constituents of a larger complex 

 known as nucleic acid, which also contains a sugarlike principle. 

 To effect the liberation of the nitrogen and phosphorus in available 

 forms, this complex must be broken up into its constituent parts. 

 This has been done in the laboratory and the nitrogen and phos- 

 phorus obtained in such forms as are utilizable by plants. The best 

 methods of rendering the unavailable forms effective for crop growth 

 are being studied. 



The Elkton clay in Mandand has been very exhaustively studied 

 in regard to the nature of the organic matter which differentiates this 

 from other soil types in the same region. This especially poor soil 

 contained very little of the weathered humus. The nature of the 

 organic matter contained therein has been studied and was shown to 

 contain liquid fats, fatty acids, etc. 



Peat soils of the Coastal Phiins were studied to determine the crops 

 to which they are adapted and their fertilizer and lime requirements. 

 The nature of the materials composing peat soils was determined by 

 the methods developed in the laboratory of this bureau. An espe- 

 cially prominent problem in connection with peat lands is the eco- 

 nomic utilization of the comparatively large but unavailable nitrogen 

 supply. The organic nitrogen forms have been studied and much 

 valuable information gained on this important agricultural problem. 

 From these soils there have also been isolated resins, waxes, fatty 

 substances, paraffin h3'drocarbons, and other bodies in definite crys- 

 talline forms, all of which throw new light upon the processes of 

 peat formation and its economic utilization. 



Park and lawn soils from city parks and Government reservations 

 have been i^tudied in order to formulate the best means for their im- 

 provement, preservation, and upbuilding. Especial attention has 

 been given in this connection to a study of the soil types best suited 

 for building lawns and parks and the soil treatment and management 

 requisite for a successful lawn. The association of grass and trees 

 has been studied and particular attention given to the nature of the 

 organic materials in such soils. Several unsuccessful laAvns or parks 

 were traced to the presence of harmful organic substances which 

 hindered plant growth. The study of these compounds has sug- 

 gested methods for their elimination and for preventing their 

 formation. 



Fertilizer requirements of soils were made on soil types from 

 various parts of the United States. The soils studied were the Cecil 



