THE NORFOLK SAND. 7 



which are well served by rail and water transportation, give it an 

 added value for the production of the market-garden crops. 



As a result the Norfolk sand may be characterized as the most 

 valuable of the early trucking soils from New Jersey to the southern 

 limit of North Carolina. Even in more southern regions where the 

 extreme early maturit}^ of the crop is not so great an advantage, the 

 Norfolk sand still constitutes a valuable truck soil. The type is a 

 special-purpose soil rather than one suited to general farming. 



IMPROVEMENT IN SOIL EFFICIENCY. 



There is probably no single improvement in the efficiency of the 

 Norfolk sand which would equal that of the incorporation of a suf- 

 ficient amount of organic matter in the surface soil to render it some- 

 what more retentive of moisture and less liable to drought during the 

 summer. The soil is so loose and open that to a depth of 6 or 8 inches 

 it is thoroughly aerated and subject to all of those processes of oxida- 

 tion which tend to destroy any organic matter which may be incor- 

 porated with it. Even under natural conditions and before it is oc- 

 cupied for cultivation the tendency has been toward the destruction 

 of such organic matter as might naturally be incorporated with a 

 virgin soil. Especially under intensive cultivation is there a strong 

 tendency toward a loss of humus. Nearly all of the processes of cul- 

 tivation give rise to greater aeration than is normal in the natural 

 soil and therefore tend toward the destruction of organic matter. 

 In consequence the trucker or the general farmer upon the Norfolk 

 sand who would maintain the productivity of his soil must take 

 constant care of it. It is not sufficient to depend upon commercial 

 fertilizers, either the general or special brands, for the maintenance 

 of soil fertility or productivity upon this soil. Practically no increase 

 in the crop yields may be permanently obtained, and in many cases 

 the normal crop yield may not be secured through any long period 

 of years unless a strenuous effort is made toward the incorporation 

 of organic matter in the surface soil each year. For this purpose a 

 green manuring crop grown during the winter months, to be plowed 

 under prior to the planting of the spring truck crop, is highty recom- 

 mended. 



For such purposes several crops are grown in the Coastal Plain 

 Kvtion. In all of the more northern regions crimson clover has been 

 used extensively and with very satisfactory results. In the same 

 general region and southward cowpeas, sown either between the rows 

 of the intertilled crop at a time when it has nearly reached maturity 

 or broadcast over the entire area of the field, constitute a very 

 valuable green manuring crop. In more southern locations crops of 

 hairy vetch and of velvet beans may also be grown during the winter 



