Mechanical Root-Disruption Practices and Their Effect on Circling Roots of Pot-Bound Tilia Cordata Mill. and Salix Alba L. ‘Niobe’    (View PDF)

Patrick J. Weicherding, Chad P. Giblin, Jeffrey H. Gillman, David L. Hanson, and Gary R. Johnson

Abstract: Pot-bound Tilia cordata Mill. and Salix alba L. ‘Niobe’ were planted in a Waukegan silt loam soil in June 2003 at the University of Minnesota TRE nursery in St. Paul, Minnesota. Before planting, the root balls of the container-grown plants were mechanically disrupted using one of three standard root pruning practices recommended to correct circling roots: scoring (slicing), butterfly pruning, or teasing. Root balls on the controls were left undisturbed. The trees were harvested in October 2004. Roots growing beyond the original root ball were counted and measured for diameter growth to assess the effectiveness of the root pruning techniques in encouraging root growth outside of the original root ball. All root disruption treatments resulted in increased fibrous root growth, but no mechanical root disruption method was significantly better than root balls left undisturbed.

Keywords: Butterfly pruning; circling roots; girdling roots; mechanical root disruption; pot-bound; root pruning; scoring; slicing; teasing

https://doi.org/10.48044/jauf.2007.005