316 MISCELLANEOUS FARM SUBJECTS 



a smaller quantity of nutrient material in solution. They also have 

 generally a lower absorptive capacity and presumably permit a much 

 more rapid and at times possibly an excessive oxidation. 



When, aside from texture, the physical and chemical properties 

 of the soil and its method of formation are alike, we have what is 

 called a soil series, extending from the coarse gravelly or sandy soils 

 on the one side to the finer silt and clay soils on the other, and in 

 such a series the texture of the soil determines the distribution of 

 crops. In some soils the mineral particles have a grandular ar- 

 rangement of flocculated masses, making the soil loose and porous. 

 In others the grains appear to have no such coherency, but exist in 

 a compact form, making the soil hard and compact. We also have 

 the gumbo and adobe soils and others that are exceedingly plastic. 

 Then, again, the amount and character of the organic matter in- 

 fluences not only the productive capacity of the soil, but its adapta- 

 tion to crops, while the color of the soil has to be considered as indic- 

 ative of certain obscure chemical or physical relations that influence 

 the adaptation and productivity. 



Other things being equal, as the texture varies the water-holding 

 capacity of the soil will also vary, the light sandy members of the 

 series or the sandy types holding on the average not over 4 per cent 

 of water, while the clay members at the other end of the series will 

 hold 20 per cent of moisture. With this difference in moisture there 

 is a corresponding difference in the soil atmosphere and oxidation 

 is usually much more rapid in the sandy members than in the clay 

 members of a series. 



Color as Indicating Fertility. In the past too little attention 

 has been given to what appears to be the influence of color, or some 

 associated properties of the soil which determines the color, on the 

 yield and qualities of the crop. 



Careful observation has shown that the black, red, yellow, blue, 

 and white soils of the Coastal Plains are essentially different in 

 their properties and in their relation to the yield and quality of crops. 

 The soil man knows that on the red soils of the Orangeburg series, 

 whether the Orangeburg sandy loam, the Orangeburg loam, or the 

 Orangeburg clay, he will get a tobacco from Cuban seed which has 

 a certain texture and a certain aromatic quality which can not be ob- 

 tained from the same seed planted on the yellow soils of the Norfolk 

 series, in adjoining fields, and under identical climate conditions. 

 The texture of the soil in this case will influence the texture of the 

 leaf. On the light soils of the Orangeburg series he will know that 

 the product will be a thinner leaf and that on the heavier soils of the 

 same series the leaf will be heavier and contain more gum, but will 

 have the same aromatic qualities. On the yellow soils of the Nor- 

 folk series in the South Atlantic and Gulf States he will get the finest 

 quality of wrapper leaf of the Sumatra type, without aroma, with 

 little gum, but with an elastic texture and a bright glossy finish which 

 can not be equaled on the red Orangeburg soils. Why the color of 

 the soil should indicate this is not apparent. It does not seem proba- 

 ble that it is due to the actual difference in color or even to the 



