1919] 



Pendleton: A Study of Soil Typix 



413 



Potassium as K 2 



Diablo clay adobe. — There is a moderate range in the variation in 

 the amount of K 2 within this type, the lowest amount being 1.48% 

 and the highest 2.06%, the four samples averaging 1.71 % (table 28, 

 figs. 15-18). 



Altamont clay loam. — A greater variation, from 1.09% to 2.14', . 

 of K.,0, occurs in the three samples of this type. The average is 

 1.74%. 



San Joaquin sandy loan}. — This type shows the greatest variation, 

 from 0.98% to 2.84%. But even so, the the largest quantity of K.,0 

 is less than three times the smallest. 1.889? K.,0 is the average of 

 the eight samples. Nos. 11 and 12 of this type show the smallest 

 amounts of K 2 of any of the twenty-four samples. 



Ilanford fine sandy loam. — The variation in the K L ,0 content of 

 the samples of this type is not great — from 1.73%) to 3.16%, with 

 the average of 2.33%. This is the highest average, as the Diablo clay 

 adobe samples show 1.71%, the Altamont clay loam 1.74%, and the 

 San Joaquin sandy loam 1.88%. Because of the considerable range 

 in the amounts of K 2 for the several samples of a type, and because 

 of the many overlappings of the values for one type over another. 

 the averages do not mean much and do not show the soils within a 

 type to be closely similar, nor do the} 7 show the types distinct. 



