E.F. Gilman
1988
Tree root spread in relation to branch dripline and harvestable root ball
HortScience 23 (2): 351-353
 
Ninety-one percent to 95% of field-grown 3-year-old root systems of Gleditsia tricanthos L., Populus x generosa A. Henry, and Fraxinus pennsylvanica Marsh were outside of the harvestable root ball. Seventy-seven percent of the Populus root system was growing beyond the branch dripline, whereas 59% and 54% were outside of the Gleditsia and Fraxinus driplines, respectively. Root spread to branch spread ratios are discussed.
 
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