26 



CIRCULAR 303, U.S. DEPARTMENT OF AGRICULTURE 



In figure 14 is shown the root development of a Baldwin tree 54 

 years old, with a trunk girth of 80 inches, grown on Dunkirk silt 

 loam, a soil of group 1. The roots are well distributed but are most 

 abundant near the surface and in the thin layers of clay near the bot- 

 tom. They are least abundant in the lower part of the very fine sandy 



© ROOTS MORE THAN ONE INCH IN DIAMETER •■ S* 



6 8ETWEEN ONE HALF AND ONE INCH IN DIAMETER 



X SMALLER DEAD ROOTLETS 



LER ROOTS AND RO0TLET6 

 .ARGE DEAO ROOTS 



Figure 14. — Root penetration of a Baldwin apple tree on Dunkirk silt loam, a soil of group 1: A, brown 

 silt loam; B, light-brown silt loam; C, gray and rust-brown silt loam; D, light-brown silt with lenses of 

 red clay, E, light-brown very fine sandy loam with thin layers of light-red and olive-brown clay; and 

 F, compact very fine sand. 



loam layer and stop abruptly at the surface of the compact very fine 

 sand layer at a depth ranging from 6 to 7 feet. 



Figure 15 shows the root development of a Baldwin tree 55 years 

 old, with a trunk girth of 100 inches, growing on Dunkirk silt loam. 

 The heavy and well-distributed rooting will be noted, also an almost 

 total absence of roots in layer E of compact very fine sandy loam. 

 Roots which extend into the lower part of the profile are evidently 

 the branches of larger roots which penetrate this compact layer nearer 

 the tree trunk. Roots were found to a depth of more than 9 feet. 



