Root growth near vertical root barriers after seven years

Abstract

Vertical root barriers are used to redirect root growth to greater depths in the soil, thus reducing damage to the sidewalks. This study was conducted to examine root growth patterns near a variety of vertical root barriers. Thirty willow oaks (Quercus phellos) were planted in November 2000 and one of the following treatments was installed on two sides of each tree: Biobarrier, DeepRoot Universal Barrier, DeepRoot Universal Barrier with Spin Out, Tex-R, Typar Geotextile 3801, or a no-barrier control. In March 2007, the second 15-tree block was excavated to reveal the root system outside the barrier. All five root barriers significantly reduced the amount of root growth compared with the control trees. There were no differences among the products tested. © 2009 International Society of Arboriculture.