Strengthening our Community Tree Canopy Through Education

Module #7: Root PruningLaura Sanagorski, Environmental Horticulture Extension Faculty

Strengthening Our Community Tree Canopy

2012 Urban Forestry Series

This series is a part of a project titled “Strengthening Our Community Tree

Canopy Through Education”. This project is made possible by  a grant

through the 2011 National Urban and Community Forestry Grant Program

and the Florida Department of Agriculture and Consumer Services,

and the Florida Forest Service.

Root Pruning

Root Pruning – the Need

Correct defects at planting

Reduce size of rootball for transplant

Address conflict with hardscape

Root Pruning – Defects discovered at planting Circling roots Matted roots

deflected downward

Excess soil on top of rootball

Photo: UF Laura Sanagorski

Circling / Girdling – roots that grow around the trunk of a tree rather

than laterally away from it that constrict the other

roots or the trunk, restricting growth.

Circling / Girdling root systems often cause failure

Photo: UF Laura Sanagorski

Circling / Girdling root systems often cause failurePhoto: UF Laura

Sanagorski

Circling / Girdling root systems often cause failure

Photo: UF Laura Sanagorski

Circling / Girdling root systems often cause failure –

can this be avoided?

Photo: UF Laura Sanagorski

Photos: UF Laura Sanagorski

Planting space, planting depth, and/or improper

mulch can cause circling / girdling root systems

Root Pruning – Equipment

Sharp Shovel

Pruning Shears

Air Spade / Air Excavator

Trench cutter

air excavator ()

Luana Vargas, International Society of Arboriculture, Bugwood.org

An arborist using a tree spade to root prune

Root pruning at planting - Slice & remove outer

½ - 1” of rootball – preferable to radial

slicing

Photo: UF Laura Sanagorski

CIRCLING ROOT REGENERATION

Defective roots can often be cut as remedy

Root pruning – How Much? No more than

25% - 30% Severance of

major support roots may compromise integrity

As trees age, they can’t withstand as much

Photo: UF Laura Sanagorski

Root pruning - staking A must if

major roots or large percentage are cut

Photo: UF Laura Sanagorski

Strengthening our Community Tree Canopy Through Education

Module #7: Root PruningLaura Sanagorski, Environmental Horticulture Extension Faculty