Container Type Affects Root Development of Chanticleer® Pear (Pyrus calleryana ‘Glen’s
Form’) During Landscape Establishment
Alison Stoven O’Connor, James E. Klett, and Anthony J. Koski
Abstract: While there are many advantages to producing woody plants in the industry-standard black plastic (BP) container, circling and girdling roots on plants grown in them may reduce transplant success, predispose plants to stress, shorten life span in the landscape, and increase the potential for the development of hazard trees. Plants grown in fabric containers may have fewer circling and girdling roots, possibly eliminating transplant problems sometimes seen with plants grown in BP containers. This study evaluated post-transplant root and shoot growth of Pyrus calleryana ‘Glen’s Form’ (Chanticleer®) produced using three container types: black plastic, Root Pouch® (RP) and Smart Pot® (SP). Researchers found no container effects on aboveground growth one, two, and three years following transplant into the landscape. All trees doubled their root dry weight annually over the three-year study. No container effects were found for any measured root parameters one year after planting. However, two and three years following planting, trees grown in RP and SP containers showed greater total root growth beyond the original root ball than BP-grown trees. Three years after planting, 72% of all root growth of trees grown in BP containers was within the original root ball, while more than one-third of all roots of RP- and SP-grown trees were found outside of the original root ball. Researchers believe that fabric containers should be considered as alternatives to BP containers because they may enhance root growth of transplanted trees and reduce the formation of future circling and girdling roots.