E.F. Gilman, I.A. Leone, and F.B. Flower
1987
Effect of soil compaction and oxygen content on vertical and horizontal root distribution
J. Environ. Hort. 5 (1): 33-36
 
Gleditsia tricanthos var. inermis seedlings were field planted in compacted and non-compacted soil in both normal oxygen and reduced oxygen soil atmosphere. Entire root systems were excavated and mapped. Compaction caused significantly shallower roots in normal and reduced oxygen areas. Roots in the reduced oxygen area were not significantly shallower than in normal oxygen areas. Root spread was correlated with stem diameter and branch spread. Lateral roots extended three times as far from the trunk as did the branches.
 
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