368 



SOILS. 



amplifies a case where although potash is exceptionally high, 

 only scrubby oak growth is produced in presence of an amount 

 of lime that in sandy lands would show profuse lime growth. 



TABLE ILLUSTRATING THE NEED OF HIGH LIME-PERCENTAGES IN HEAVY 



CLAY SOILS. 



All of the soils in this table are heavy clays, very difficult to 

 till; in all, the lime-percentage falls below .5^ ; and none 

 bear any lime vegetation, the Mississippi soils having a stunted 

 growth of black jack and post oaks, such as is universally 

 known to indicate soils too poor for profitable cultivation. The 

 California soil bears stunted live oak (Q. agrifolia) ; but not 

 being as heavy as its brethren from Mississippi, though un- 

 thrifty, is more readily improved. 



Comparison with the two first sandy soils in the table on p. 352 shows, 

 that with plant-food percentages equal to, or even much below those 

 here shown, not only was vigorous lime growth present, but crop-pro- 

 duction was good and even high. 



