Street trees shall be required wherever a proposed subdivision shall average three or more lots per gross acre or where the proposed subdivision is adjacent to any existing or recorded development having street trees.
The Shade Tree Commission shall review all development and redevelopment plans meeting the above criteria to assure the planting of the proper trees.
A. 
Preferred tree species.
(1) 
All plant material used shall be selected from the following plant list. If the developer is confronted with an unforeseen problem pertaining to tree species, the Shade Tree Commission shall be consulted for advice and recommendations.
(2) 
Street trees within the same block shall be of the same species except to achieve a special effect, as approved by the Shade Tree Commission.
Small Trees (under 30 feet)
Acer campestre -- hedge maple
Acer ginnala -- Amur maple
Acer tataricum -- Tatarian maple
Amelanchier canadensis (tree form) -- shadblow serviceberry
Amelanchier laevis (tree form) -- Allegheny serviceberry
Cornus florida -- flowering dogwood
Cornus kousa -- Chinese kousa dogwood
Crataegus monogyna, selected varieties -- hawthorn
Crataegus phaenopyrun -- Washington hawthorn
Halesia carolina -- Carolina silverbell
Malus, selected varieties -- crab apple
Prunus sargentii cv. columnara -- columnar Sargent cherry
Prunus serrulata cv. Amanogawa -- Amanogawa cherry
Prunus serrulata cv. Kwanzan -- Kwanzan cherry
Pyrus calleryana cv. Chanticleer -- Chanticleer pear
Syringa amurensis japonica -- Japenese tree lilac
Medium Trees (30-45 feet)
Carpinus betulus -- European hornbeam
Carpinus betulus cv. Fastigiate -- upright European hornbeam
Cercidiphyllum japonicum -- katsura tree
Chionanthus virginica -- white fringe tree
Crataegus lavallei -- Lavalle hawthorn
Koelreuteria paniculata -- goldenrain tree
Malus cultivars -- crab apple
Adams
Snowdrift
White Angel
hupenhensis
zumi calocarpa
Becerly
Nyssa sylvatica -- sour gum
Phellodendron amurense -- Amur cork tree
Prunus yedoensis -- Yoshino cherry
Pyrus calleryana cultivars -- Callery pear
Aristocrat
Bradford
Dwarf Korean
Quercus acutissima -- sawtooth oak
Sorbus alnifolia -- Korean mountain ash
Sorbus aucuparia -- European mountain ash
Ulmus parvifolia -- Chinese elm
Large Trees (over 45 feet)
Acer rubrum (selected cultivars) -- red maple
Acer saccharum (selected cultivars) -- sugar maple
Corylus colurna -- Turkish filbert
Ginkgo biloba (male selections only) -- ginkgo
Metasequoia glyptostroboides -- dawn redwood
Quercus alba -- white oak
Quercus borealis -- red oak
Quercus cerris -- Turkey oak
Quercus imbricaria -- shingle oak
Quercus phellos -- willow oak
Quercus shumardi -- Shumard oak
Sophora japonica -- Japenese pagoda tree
Taxodium distichum -- common bald cypress
Tilia cordata -- littleleaf linden
Tilia euchlora (selected cultivars) -- Crimean linden
Tilia tomentose -- silver linden
Zelkova serrata (selected cultivars) -- Japanese zelkova
(3) 
The use of any tree other than those listed above required the approval of the Shade Tree Commission.
(4) 
Not all trees on this list are suitable for all situations. Suitability shall be determined by the Shade Tree Commission.
B. 
Acquisition of trees. Only plant material grown in nurseries shall be procured for shade tree planting. Trees should be true to form and typical of the species.
C. 
Tree specifications.
(1) 
Each tree shall be at least eight feet in height and have a diameter of at least 1 1/2 inches as measured at a height of six inches above the finished ground level.
(2) 
Plant material shall be balled and burlapped with native soil in which the material had been growing (no manufactured balls).
(3) 
The relationship between tree caliper, tree height and diameter of the root ball shall be as follows:
Caliper
(inches)
Height Range
(feet)
Minimum Ball Diameter
(inches)
1 1/2 to 1 3/4
8 to 10
20
1 3/4 to 2
10 to 12
22
2 to 2 1/2
12 to 14
24
NOTE: Trees with larger caliper trunks shall have ball diameters in proportion to their size and in accordance with accepted nursery practices.
A. 
Planting locations.
(1) 
The actual location of each individual tree shall be determined considering views, proximity of utility poles, overhead and guy wires, driveways and subsurface utility installations.
(2) 
Trees shall be planted at least 30 feet from street intersections, at least 15 feet from driveways and alleys and at least 10 feet from utility poles.
(3) 
Spacing of trees should be determined by the Shade Tree Commission according to local conditions, the species, cultivars or varieties used, their mature height, spread and form. Generally, all large trees shall be planted 40 to 60 feet on center; all medium-sized trees shall be planted a minimum of 35 feet on center; and all small trees shall be planted a minimum of 25 feet on center. Whenever possible, shade trees shall be planted alternately along each side of all streets of the development. Trees shall be spaced without regard to property lines.
(4) 
The cross-sectional location of street trees shall be as follows (as a guide):
(a) 
No overhead utility wires. Trees shall be located within right-of-way, on-center between the curb and sidewalk.
(b) 
Utility wires overhead. Trees shall be located preferably between the sidewalk and building setback line and at least three feet from the sidewalk. Small trees may be planted under utility wires with Shade Tree Commission approval.
B. 
Planting specifications.
(1) 
Tree pits shall be at least 10 inches wider in diameter than the diameter of the root ball. Unless building debris is encountered, the hole shall be excavated to a depth no greater than to permit the top of the ball to be level with the rim of the hole. All encountered debris should be removed to a minimum depth of 30 inches.
(2) 
Planting time. Except where waived by the Shade Tree Commission, trees within the same block shall be planted at the same time. Balled and burlapped material may be planted during any period of the year when the soil is frost-free and friable.
(3) 
The burlap and twine covering the upper half of the ball shall be rolled back or cut away after the plant has been set.
(4) 
Trees shall be staked with no less than two-by-two-inch stakes driven 2 1/2 to three feet into the ground. Two stakes shall be required for trees less than two inches in caliper, and three for trees greater than two inches in caliper. The trunk shall be protected by placing a short piece of three-fourth-inch-diameter, two-ply reinforced hose around the guy wire where it comes in contact with the tree. All stakes shall be of the same height for uniform appearance and support.
(5) 
The planting hole shall be backfilled to 3/4 full with soil, followed by 10 gallons of water. When the water has been absorbed, the hole shall be filled with topsoil and tamped lightly to finished grade.
(6) 
Upon completion of the transplanting operation, a wood chip or bark mulch, two inches deep, shall be placed over the planting area.
(7) 
All unused soil or other debris resulting from the planting or plant material shall be removed from the project area.
A. 
Maintenance.
(1) 
Plant maintenance shall begin immediately after each plant is satisfactorily installed and shall continue until final inspection by the Shade Tree Commission.
(2) 
Plant maintenance shall include, but need not be limited to, replacing mulch that has been displaced by erosion or other means, maintaining stakes and guys as originally installed, watering when needed or directed and performing any other work required to keep the plants in a healthy condition. An adequate moisture supply is estimated to be the equivalent of one inch of water per week, delivered at weekly intervals in the form of rain or augmented as required by periodic watering.
(3) 
The developer shall remove and replace all dead, defective and rejected pants as occur during this period.
B. 
Guaranty. In addition to other standard provisions, the developer's improvement bond shall also provide for the following:
(1) 
Maintenance necessary during establishment period.
(2) 
Replacement in kind, or with a substitute acceptable to the Shade Tree Commission, of all plant material which is not in a healthy growing condition, which has died back or is beyond normal pruning limits.