RT Journal Article SR Electronic T1 The Effect of Backfill Soil Texture and Planting Hole Shape on Root Regeneration of Transplanted Green Ash JF Arboriculture & Urban Forestry (AUF) FD International Society of Arboriculture SP 130 OP 135 DO 10.48044/jauf.1992.029 VO 18 IS 3 A1 Watson, Gary W. A1 Kupkowski, Gary A1 von der Heide-Spravka, Kerstin G. YR 1992 UL http://auf.isa-arbor.com/content/18/3/130.abstract AB Forty-five Summit green ash trees (Fraxinus Pennsylvania ‘Summit’) were planted on a compacted clay soil site. Unamended soil, amended soil, and friable topsoil were used as backfill, in combination with holes slightly larger than the root ball, twice, and 3 times the diameter of the root ball. Numerous roots were able to penetrate the interface between backfill soil and clay subsoil in all treatment combinations. Root densities were higher in all backfill soils, but not significantly, due to the differences in soil characteristics rather than inability to grow through the interface. Larger planting holes with sloped sides helped to direct roots up to the more favorable soil at the surface if they were not able to penetrate the clay subsoil, preventing them from being trapped in the planting hole.