WATER OF SOIL IN ITS RELATION TO PLANTS 197 



by a number of soil conditions. Important among these is 

 texture, whicli in itself really represents a group of soil con- 

 ditions. In general the wilting point is much higher on a 

 jSjie soil than one of a coarse nature. The following data from 

 Briggs and Shantz ^ is interesting in this regard. The wilt- 

 ing coefficient is shown to lie much nearer the hygroscopic 

 coefficient than to the figure representing the maximum ab- 

 sorption capacity as determined by the Hilgard method. 



Table XXXVII 



RELATION OF THE WILTING COEFFICIENT TO THE TEXTURE OF THE 



SOIL, THE HYGROSCOPIC COEFFICIENT AND THE CALCULATED 



MAXIMUM ABSORPTIVE CAPACITY OF THE SOIL 



FOR WATER. 



Soil 



Hygroscopic 



COEJb'Ji'ICIENT 



Wilting Point 



Calculated 



Maximum 



Absorption 



Capacity 



Coarse sand 



Fine sand 



.5 

 1.5 

 2.3 

 3.5 

 4.4 

 6.5 

 7.8 

 9.S 

 11.4 



.9 

 26 

 3.3 



4,8 



6.3 



9.7 



10.3 



13.9 



16.3 



25.7 



28.5 



Fine sand 



30.5 



Sandy loam 



Sandy loam 



Fine sandy loam . . 

 Loam 



34.9 

 39.2 

 49f.l 

 50.8 



Loam 



61.3 



Clay loam 



6&.2 



In studying the correlation of this wilting coefficient to 

 soil conditions Briggs and Shantz^ advanced the following 

 relationships. Expressed as formulae, they represent methods 



* Briggs, L. J., and Schantz, H. L., The Wilting Coeffieient for Dif- 

 ferent Plants and %ts Indirect Determination; U. S. Dept. Agr., Bur. 

 Plant Ind., Bui 230, p. 65, 1912. 



See also Heinxieh, E., t^ber das Vermogen der Pflanzen den Bodenen 

 Wasser bu erschopfen; Jahresbericlit der Agr.-chem., Band 18, Seite 368- 

 372, 1875. 



* Briggs, L. jr., and Shantz, H. L., The WHtim^g Coefficient for Mf- 



