Relative Importance of Tractable Factors Affecting the Establishment of Transplanted Holly1

Abstract The influence of root and shoot pruning on the growth of transplanted 3-year-old Ilex crenata ‘Convexa’ × I. crenata ‘Stokes’ was determined under various backfill regimes. Root pruning reduced shoot dry weight increment 24% but only reduced root dry weight increment 6%. Root pruning caused water deficits to develop which can quantitatively account for the reduced shoot growth. Shoot pruning reduced root dry weight increment without influencing shoot dry weight increment. Adjustments of the means for altered tissue water content caused by shoot pruning resulted in decreased root and shoot dry weight increment. Root and shoot pruning influenced plant growth directly — by influencing growth mediating processes, and indirectly — by influencing plant water relations. Root growth was influenced primarily by growth mediating processes while shoot growth responded to both growth mediating processes and plant water relations.