SOIL PROFILE AXD ROOT PEXETRATIOX BY APPLE TREES 27 



Figure 16 shows a Baldwin apple tree with a trunk of 100 inches in 

 circumference, the root development of winch is shown in figures 15 

 and 17. 





10 



i:^»-4 



\$> 



>A 



C 



>D 



^E 



^F 



^G 



S ROOTS MORE THAN ONE INCH IN DIAMETER •• SMALLER ROOTS AND ROOTLETS 



e BETWEEN ONE HALF AND ONE INCH IN DIAMETER ® LARGE DEAD ROOTS 



X SMALLER DEAD ROOTLETS 



Figure 15.— Root development of a Baldwin apple tree on Dunkirk silt loam, in the subsoil of which is a 

 thin layer of compact very fine sandy loam: A, brown silt loam; B, light-brown silt loam; C, gray and 

 rust -brown mottled silt loam; I), dull-red stratified clay; E, grayish-brown compact very fine sandy loam; 

 F, dull-red and olive-brown stratified clay; and G, compact sand and gravel. 



In order to see how completely the roots permeate the soil mass, a 

 strip 1 foot wide extending from" the top to the bottom of the excava- 

 tion used in figure 15 was" selected. On this strip of side wall the soil 



