Toronto District School Board
Grounds Guideline
GU.FAC.011 - Version 1.0
For Trades
Approved by FS Leadership
Team, June 5, 2013
Plant native species
Every effort should be made to
plant native species. Diversity of
species within a specific school
should also be considered when
selecting trees. Planting trees that
are not native is sometimes
acceptable when environmentally
sensitive areas, such as ravines,
will not be affected. In all cases,
invasive non-native species are not
acceptable.
Facility Services
Planting Trees in Hard Surfaces
and in Planters
Introduction
The TDSB is committed to well-planted and properly maintained
trees. Trees, unlike buildings, increase in value over time and are
an asset we can enjoy now and in the future.
Our first priority is to provide shade in areas where children are
actively playing. Often, this means planting trees in paved play
areas (asphalt). Trees planted in paved areas also reduce the
urban heat island effect and can help cool buildings.
Trees in paved areas may be planted in one of two ways:
1. Level to the surrounding grade and covered with unit or
grid pavers, or permeable rubber surfacing.
2. In raised planters made of armour stone, precast concrete,
or timber.
—————————————–
Native Tree Species Suitable for
Hard Surfaces*
Deciduous species:
 Hackberry (Celtis occidentalis)
 Honey Locust (Gleditsia
triacanthos)
 Silver Maple (Acer saccharinum)
 Red Maple Silver Maple cross
(Acer freemanii)
Coniferous species:
 White Spruce (Picea glauca)
*availability may vary depending
on season
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It is important to ensure that trees have the best possible start by
following the planting instructions below carefully.
Tree Health
When the nursery delivers a shipment of stock to the TDSB yards,
the Grounds Team Leader or Designate will inspect the trees to
ensure they are healthy and undamaged. He or she will check the
trunk for damage through the burlap wrap. Trees that fail to meet
TDSB standards will be returned to the nursery for replacement.
The planting crew is also responsible for ensuring that only healthy,
undamaged trees are planted in our schools. Take a few minutes to
inspect the trees one more time before transporting them to the
school.
How to Identify a Healthy Tree

all trees must be viable (living), free from pests and
disease, and undamaged

between digging and delivery to the school, roots must not
be exposed to drying winds, sun, or frost

root balls must be free from weeds
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
shade trees must have straight sturdy trunks, with a sixfoot clear stem, and a well-branched and balanced head

trees with broken or damaged (e.g., from abrasion) trunks
or branches are not acceptable
Check before you plant
Many schools have master plans
for their yards that could affect
where trees can be planted. Some
schools have had on-site design
consultations from the School
Ground Design Consultants, and
are trying to establish outdoor
classrooms or nature study areas
as part of the EcoSchools program.
Schools are responsible for
informing the Grounds Team
Leader of their plans and supplying
them with a copy of the design.
Every effort should be made to
accommodate these plans.
ii) Utility locates can take up to
eight weeks and can affect the
location of the planting. The
equipment operator must have a
copy of the site scan. The school
should also keep a copy for its
reference.
A tree pit excavated to a diameter
of 3000 mm (10 ft.) will
accommodate roughly 6 or 7 cubic
yards of amended soil (planting
mix). It is essential to maximize
the soil volume to ensure the
health of the tree.
When You Arrive at the School
In most cases, the Grounds Team Leader or Designate will have
visited the school at least six weeks in advance of planting day to
determine the location of the trees and to arrange for utility locates
and stakeouts to be done.
Excavating the Tree Pit
Trees are a long-term investment and the size of the tree pit is
very important to the tree’s survival.
1. All single trees planted in hard surfaces require a minimum
opening of 3000 mm x 3000 mm (10 ft. x 10 ft.).
2. Leave a 152 mm (6 in.) compacted gravel base on the
inside edge of the asphalt cut so that the excavated tree
pit is 2700 mm x 2700 mm (9 ft. x 9 ft.). This creates a
firm base to support the permeable pavers or the planter
(timber, concrete, or stone).
3. Use an excavator for digging the hole. Augers must not be
used for planting ball-and-burlapped trees. For details on
excavation, see Excavation Guideline (coming soon).
4. Ensure that the granular base and rubble are removed as
well as the asphalt for all trees, including those to be
planted in planters.
—————————————–
In some cases, there may be
additional unforeseen costs if the
surface beneath the asphalt is not
conducive to planting.
—————————————–
5. Use a shovel or the teeth of the backhoe to loosen the soil
around the sides of the pit to promote healthy root growth.
Do not disturb the soil at the bottom of the tree pit.
6. In most cases, the tree pit should be no deeper than the
depth of the root ball. If the root ball is to be covered over
with pavers, the tree pit should be the depth of the root
ball plus an additional 50 mm (2-3 in.).
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Planting Mix: Existing soil plus amendments

a tree pit excavated to the specifications above (9 ft. x 9 ft.
x approx. 2 1/2 ft.) will accommodate roughly 6 or 7 cubic
yards of amended soil (planting mix). It is essential to
maximize the soil volume to ensure the health of the tree

raised stone, concrete, or timber planters can
accommodate an increased volume of soil and are
preferable for the health of the tree

the planting mix for all new trees should be approximately
2/3 existing soil from the tree pit excavation and 1/3
composted organic enviro-mix amendments (a blend of
mushroom compost, sand, sawdust, and peat)

mix existing soil and amendments together before filling in
the pit once the tree is in place
Building Planters
Trees planted in armour stone, precast concrete, or timber planters
are preferable to those covered with continuous surfacing because
they can accommodate an increased volume of soil. For detailed
instructions on how to install planters see Landscape and Child
Development: A Design Guide for Early Years—Kindergarten PlayLearning Environments.

for armour stone planters, please refer to figure 1.21

for precast concrete planters, please refer to figure 1.22

for timber planters, please refer to figure 1.32
Tree size
Deciduous trees planted at the
TDSB should have a caliper
(diameter) of at least 75 mm (3
in.) and a stem clear of branches
to 1.8-2.1 m (6-7 ft.). Coniferous
trees should be between 2.4-3 m
(8-10 ft.) high. Trees smaller than
this are called “snaplings” because
they are so vulnerable to damage.
Planting the Tree
All trees need to be transplanted carefully to avoid damage. Handle
trees coming off the truck with care. Cut all ties from the branches
and crown of the tree before planting.
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
For trees to be covered with hard surfacing:
1. Plant the tree approximately 50 mm (2 in.) lower
than the surrounding grade to allow for the high
performance bedding (HPB) and the permeable
pavers.
2. Place the tree on the undisturbed soil at the bottom
of the tree pit. Ensure that the tree is upright. Do not
pull on the tree trunk to straighten it. Straighten it
mechanically, if needed (i.e., remove the tree from
the pit or use a board between the perimeter and the
root ball).
3. Remove the burlap from the trunk to inspect the
trunk for cracks or scrapes.
4. Fill with planting mix around the bottom half of the
root ball and tamp down by foot to secure the tree in
place. This will remove air pockets, minimize soil
settlement, and stabilize the tree in an upright
position. No mechanical compaction of the backfill is
permitted.
5. Cut open the wire basket and remove the burlap,
rope, or nylon ties from the upper third of the root
ball.
6. Check again that the tree is planted straight. Fill the
rest of the tree pit with planting mix to the top of the
root ball and tamp lightly by foot.

Double-wrapped trees
Watch for trees that may have
been double-wrapped with plastic,
in which case remove both plastic
and burlap.
Trees in planters:
1. Begin filling the planter with planting mix after the
tree is placed inside in an upright position. Be sure
not to pull on the tree trunk to straighten it.
Straighten it mechanically, if needed (e.g., remove
the tree from the pit or use a board between the
perimeter and the root ball).
2. Remove the burlap from the trunk to inspect the
trunk for cracks or scrapes.
3. Cut open the wire basket and remove the burlap,
rope, or nylon ties from the upper third of the root
ball.
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4. The planter should be filled with planting mix up to
the base of the trunk (the top of root ball).
5. Volume of the planting mix should allow for 100-150
mm (4-6 in.) of mulch to be contained in the planter
no higher than 50 mm (2 in.) below the top of the
planter.

Remove all strings and ropes from the trunk after planting.
Installing Surfacing
To provide a safe continuous surface for play (for trees without
planters), the opening in the asphalt must be covered with either

permeable unit pavers (e.g., Eco-Optiloc)

concrete grid pavers (e.g., Turfstone)

permeable rubber safety surfacing around the base
For detailed instructions on how to install surfacing, please refer to
Landscape and Child Development: A Design Guide for Early
Years—Kindergarten Play-Learning Environments.

for permeable unit pavers, see figure 1.11

for concrete grid paving, see figure 1.12
Permeable Unit Pavers
(Eco-Optiloc)
Concrete Grid Paver
(Turfstone)

12% permeable (less water
will reach the tree roots)

28%
percent
permeable
(improved water absorption)

Small units (children can
remove them)


Smaller gaps between the
pavers
Each unit weighs 60 lbs.
(children will not be able to
lift them)

Holes in the Turfstone need
to be filled with HPB, which
can be kicked out by children, creating voids in the
surface
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Permeable Unit Pavers (Eco-Optiloc)
1. Use 80 mm (3 1/8 in.) thick precast concrete unit pavers
units, 400 mm x 600 mm (16 in. x 24 in.), bedded on high
performance bedding (HPB).
2. Allow a 600 mm x 600 mm (2 ft. x 2ft.) opening in the unit
pavers around the base of the tree.
3. The top of the unit pavers should be flush with the finished
grade of the adjacent asphalt paving.
Concrete Grid Pavers (Turfstone)
1. Use 80 mm (3 1/8 in.) thick Turfstone units, bedded on
high performance bedding (HPB).
2. No cutting of the Turfstone is required.
3. Allow a 600 mm x 600 mm (2 ft. x 2ft.) opening in the
Turfstone around the base of the tree.
4. The top of the Turfstone pavers should be flush with the
finished grade of the adjacent asphalt paving.
5. Consider using the permeable rubber safety surfacing in
the Turfstone voids.
Mulching the Tree
Trees in planters require mulch to reduce soil erosion, root
exposure and soil compaction. Mulch also keeps the roots cool and
moist.
1. Mulch each tree with approximately 2 cubic yards of tub
grinder (shredded bark/utility) mulch.
2. Mulch to a depth of 100-150 mm (4-6 in.).
3. Mulch in a doughnut shape at the base of the tree trunk to
keep the moisture away from the base.
4. Mulch must be contained within the planter, no higher than
50 mm (2 in.) below the top of the planter.
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Protecting the Tree: Building a Sturdy Cage
Deciduous trees in active play areas need to be protected with a
wire mesh tree cage until the bark is established.

place a minimum of 3 regular 2400 mm (8 ft.) T-bar stakes
a minimum of 300 mm (1 ft.) from the trunk of the tree,
with the flat sides out. Drive stakes to a depth of at least
300 mm (1 ft.) into the undisturbed soil below the root ball

each tree requires approximately 2700 mm (9 ft.) or 54
squares of 10-gauge galvanized welded wire mesh, with 50
mm x 50 mm (2 in. x 2. in.) squares. The wire mesh
should be 1200 mm (4 ft.) high

the horizontal wires of the mesh should be on the outside
of the cage. (This is opposite to the way the mesh comes
on the roll.) Use the 50 mm (2 in.) inch cut-off tabs to
secure the cage to itself, overlapping by 3 squares. The
three-square overlap should be located between the T-bars

fasten the mesh wire to the T-bars to form a circular cage
around the trunk. Use 12 gauge merchant wire, 3 ties per
stake

the bottom of the cage should be 150-200 mm (6-8 in.)
above the top of the surface to create a gap between the
cage and the surface. The top of the cage should be 50 mm
(2 in.) above the tops of the T-bars

make sure that there are no sharp edges or protruding
wires
—————————————–
Keep cages on long enough!
Protective cages must stay on the
trees until they are well
established, typically for at least
five to seven years after they are
planted. In some cases, cages may
be required for up to ten years.
Trees in protective cages need to
be monitored annually to decide
when the cages should be
removed.
—————————————–
Think “re-use”
Using 2700 mm (9 ft.) of wire
mesh per tree cage allows the
cages to be trimmed and reused on
another tree after they are
removed. The wire mesh is sold in
100 ft. rolls, so one roll yields
eleven 9 ft. cages.
—————————————–
Best option for watering
The method used for watering the
trees will depend on the water
sources available at the school
(e.g., adequate hose bibs and
water pressure) and whether or not
the planting crew has access to a
water tank to transport to the site.
Some options include using long
hoses from hose bibs or accessing
the water system under sports
fields closer to the planting site.
Please discuss the best options for
watering with the Head Caretaker
at the site.
Watering the Tree

soak each new tree thoroughly after planting with at least
30 gallons (120 L) of water

natural rainfall is inadequate

if the soil settles after watering, add more soil to make it
level
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Types of Trees for Different School Ground Surfaces
Deciduous Trees in Hard
Surfaces (75 mm caliper)
Honey Locust (Gleditsia triacanthos)
Hackberry (Celtis occidentalis)
Silver Maple (Acer saccharinum)
Red Maple Silver Maple cross (Acer freemanii)
Coniferous Trees in Hard
Surfaces (250 – 300 cm tall)
White Spruce (Picea glauca)
Deciduous Trees in Soft
Surfaces (75 mm caliper)
Basswood (Tilia americana)
Hackberry (Celtis occidentalis)
Honey Locust (Gleditsia triacanthos)
Kentucky Coffee Tree (Gymnocladus dioicus)
Ironwood (Ostrya virginiana)
Red Maple (Acer rubrum)
Silver Maple (Acer saccharinum)
Sugar Maple (Acer saccharum)
Red Maple Silver Maple cross (Acer freemanii)
Black Maple (Acer nigrum)
Tulip-Tree (Liriodendron tulipifera)
Yellowwood (Cladrastis lutea)
Sweetgum (Liquidambar styraciflua)
Deciduous Trees in Groves in
Soft Surfaces
Use a variety of trees to improve biodiversity and to integrate
with curriculum goals.
Coniferous Trees in Groves in
Soft Surfaces (250 – 300 cm
tall)
Eastern White Pine (Pinus strobus)
Eastern White Cedar (Thuja occidentalis)
White Spruce (Picea glauca)
Larch (Larix laricina)
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Related Documents

Excavation Guideline (coming soon)

Landscape and Child Development: A Design Guide for Early
Years—Kindergarten Play-Learning Environments

Tree Planting in Soft Surfaces
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