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FiG. 132. Two diagrams illustrating the distribution of the roots of white pine 

 in soil profiles having layers of different texture, color, water content, and aeration. 

 After H. J. Lutz, Yale Forestry Bulletin 44, 1937. 



Diagram of soil profile (A). Uppermost layers of white pine debris and fungous 

 mycelia. Horizon A, fine sandy loam, dark brown above, light brown below. 

 Horizon B, fine sandy loam, brown slightly mottled. Horizon C, loam above, 

 coarse sand below. 



Diagram of soil profile (B). Loamy coarse sand in horizon A; color brownish 

 gray, motded. Horizon B, dark brown coarse sand. Horizon C, gray in color, 

 gravelly, coarse sand except layer of fine sand at 6 ft. below surface. 



