When planting trees and shrubs do you need to score the root ball to disturb the surface and cut circling roots?
In publication AZ1022 under Planting Trees and Shrubs #2 it reads "Always score the root ball to disturb the surface and to cut any circling roots. This encourages roots to grow into the surrounding soil. Make a vertical cut one-fourth to one half inches deep four times around the sided and twice across the bottom". Does this hold true today as it did when the publication was issued? The reason I am asking as one nursery is telling that is not necessary.
The recommendation to score the root ball of trees and shrubs is still valid as it prevents future problems of root circling that can be detrimental to plant health. The only time you would not have to do this is when the surface of the root ball on the outside and at the bottom has no dense matting of roots, which indicates that the plant has not been in a container too long and is at the perfect stage for transplanting. Most container plants have some degree of root matting by the time they are purchased and that is why we recommend this procedure.