§ 97.03 STREET TREE SPECIES.

   (A)   Provision of the lists. The Board of Public Works and Safety, or Parks Board, in conjunction with city staff, herewith provides a list of undesirable prohibited and desirable approved tree, shrub, and groundcover species for planting in public spaces.

   (B)   Prohibited trees. Table 1 constitutes the official prohibited street tree species for the city:

TABLE 1. Prohibited Street Trees
Common Name	Scientific Name	Issues
Alder, European Black	Alnus glutinosa	Invasive
Amur Cork Tree	Phellodendron amurense	Invasive
Arborvitae	Thuja species	Visibility obstruction
Ash, Blue	Fraxinus quadrangulata	Not planting due to Emerald Ash Borer
Ash, Green	Fraxinus pennsylvanica	Not planting due to Emerald Ash Borer
Ash, Mountain	Sorbus species	Thrives poorly, insect problems
Ash, White	Fraxinus americana	Not planting due to Emerald Ash Borer
Aspen	Populus tremuloides	Weak wood
Birch, European White	Betula pendula	Borer insects, poor survival
Birch, White Paper	Betula papyrifera	Borer insects, poor survival
Boxelder	Acer negundo	Weak wood, poor form, invasive seed
Buckthorn, Common	Rhamnus cathartica	Invasive
Buckthorn, Glossy	Frangula alnus	Invasive
Catalpa	Catalpa species	Messy fruit, weak wood
Cherry, Choke	Prunus virginiana	Messy fruit, insect problems, suckers
Cherry, common	Prunus species	Messy fruit, insect problems, suckers
Cottonwood, common	Populus deltoides	Weak wood, messy seed
Crabapple, common Named cultivars are permitted	Malus species	Messy fruit, disease problems, choose insect/disease resistant varieties if using
Elm, Siberian	Ulmus pumila	Disease problems, messy crown, weak wood
Elm, Slippery Red	Ulmus rubra	Disease problems
Fir	Abies species	Visibility obstruction
Juniper	Juniperus species	Visibility obstruction
Locust, Black	Robinia pseudoacacia	Shallow rooted, borers, cankers
Maple, Amur	Acer ginnala	Invasive seed
Maple, Norway	Acer platanoides	Shallow rooted, considered invasive
Maple, Red	Acer rubrum	Shallow rooted, weak wood, chlorotic
Maple, Silver	Acer saccharrinum	Weak wood, poor form
Mulberry	Morus species	Messy fruit, invasive seeds
Oak, Pin	Quercus palustrus	Needs acid soil
Olive Russian	Elaeagnus angustifolia	Disease prone, invasive
Pear, Callery	Pyrus Calleryana	Invasive, weak wood, short lived
Persimmon	Diospyros virginiana	Messy fruit
Pine	Pinus species	Visibility obstruction
Plum, American	Prunus americana	Weak wood, short lived, insects, disease, messy fruit
Poplars, Willows, and hybrids	Populus and salix seeds	Weak wood, fast growing
Spruce	Picea species	Visibility obstruction
Tree of Heaven	Ailanthus altissima	Invasive seed, weak wood
Walnut, Black, Butternut	Juglans species	Messy fruit, allelopathy
Willow	Salix species	Weak wood, messy

 

   (C)   Recommended trees. Tables 2, 3, 4, and 5 in division (F) below constitute the official recommended street tree species for the city, and are grouped by size, being small, medium, large, and parkway. No species other than those included on the lists of recommended street trees may be planted without special permission of the Board of Public Works and Safety, or the Parks Board, or its designee. If special permission has not been granted, the cost of removal and replacement of the undesirable tree(s) shall be charged to the individual or firm who planted the tree(s).

   (D)   Alternate trees. Alternate trees may be planted with the permission of the Board of Public Works and Safety, the Parks Board, or its designee. The trees listed here are recommendations based on known trees at the time of adoption of the ordinance incorporated in this section. Ongoing research and production yields new species that should be prohibited due to unfavorable characteristics or new species that should be recommended due to favorable hybridized characteristics. Consideration in either regard may be made for future street tree selections.

   (E)   Size. The selection of small, medium, large, or parkway trees shall be based upon the planting area available for the tree; small, medium, or large sized trees are recommended street trees based upon the distance between the curb and the sidewalk, as follows:

      (1)   Small trees (see Table 2 in division (F) below), minimum four feet distance between curb and sidewalk;

      (2)   Medium trees (see Table 3 in division (F) below), minimum five feet distance between curb and sidewalk;

      (3)   Large trees (see Table 4 in division (F) below), minimum six feet (eight feet preferable) distance between cub and sidewalk; and

      (4)   Large trees for parkways, public open spaces such as parks, and larger development areas. (See Table 5 in division (F) below.)

   (F)   Selection variety. Tree planting plans can include no more than 15% of any one tree species to protect the health of the tree canopies and protect areas from total tree devastation due to disease or insect infestation.

TABLE 2. Recommended Small Street Trees
Small trees for small spaces. Some are suitable for under power lines (under 25 feet tall). If not sure of line height, check with Power and Light Department. Minimum growing space 4 feet from curb to sidewalk.
Common Name	Scientific Name	Dimensions (Tree Height by Canopy Height)	Some Suggested Cultivars and Notes
Allegheny Serviceberry	Amelanchier laevis	25-28 feet by 20 feet	Small tree, narrow crown ‘Spring Flurry’
American hornbeam	Carpinus caroliniana	30 feet by 25 feet	Only under high power lines. Check several cultivar specs
Apple serviceberry hybrids	Amelanchier x grandiflora	20 feet by 20 feet	‘Autumn Brilliance’, ‘Princess Diana’
Carolina silverbell	Halesia carolina	20 feet by 15 feet	‘Crushed Velvet’
Flowering Crabapple	Crabapple Malus sp.	Varies	Many different types. See ‘Recommended Crabapple cultivars’ below
Flowering Dogwood	Cornus florida		Plant only on sheltered sites, tree form with shade
Pagoda dogwood	Cornus alternifolia	20 feet by 25 feet	Under power lines with wide easement
Paperbarked maple	Acer griseum	25 feet by 20 feet	Moderate salt tolerance
Persian parrotia cultivars	Parrotia persica	28 feet by 15 feet	Not salt tolerant, plant where not snow treated. ‘Persian Spire’ 25 feet by 10 feet; ‘Ruby Vase’ 28 feet by 14 feet
Shadblow serviceberry	Amelanchier canadensis	10 feet by 6 feet clumping	Multistemmed, clumping.
Summer Sprite Linden	Tilia cordata	20 feet by 15 feet	‘Halka’, ‘Summer Sprite’
Tartarian maple	Acer tataricum	25-28 feet by 20 feet	‘Pattern Perfect’, ‘Rugged Charm’
Thornless Cockspur Hawthorn	Crataegus crus-galli	15 feet by 15 feet	‘Inermis’
Winter King Hawthorn	Crataegus viridis		‘Winter King’. Plant only where thorns will not be a problem, as in natural areas
Zelkova	Zelkova serrata	24 feet by 18 feet	‘City Sprite’ zelkova
Zelkova	Zelkova serrata	24 feet by 36 feet	Zelkova ‘Wireless’. More broad than tall
Recommended Crabapple Cultivars, Malus hybrids. Chosen for good to excellent resistance to scab, fire-blight, apple-cedar rust, and powdery mildew. ‘Persistent’ fruits remain longer on tree.
‘Adams’	Pink, green foliage	20 feet by 20 feet	Red fruit 5/8 inch, persistent
‘Adirondack’	White, medium green foliage	18 feet by 10 feet	Bright red fruit 1/2 inch
‘Centurion’	Rose-red, reddish leaves	20 feet by 15 feet	Bright red fruit 1/2 inch
‘Firebird’	Red buds opening to white, dark green foliage	8 feet by 10 feet	Wider than tall
‘Lancelot’	Red buds to white blooms, gold fall color	10 feet by 10 feet	Gold fruit persistent
‘Marilee’	Double white, medium green leaves	24 feet by 10 feet	Virtually fruitless
‘Prairiefire’	Crimson buds, pink flowers, red-maroon foliage	20 feet by 20 feet	Dark red 3/8 inch persistent
‘Red Jewel’	White flowers, green foliage	15 feet by 12 feet	Brilliant red 1/2 inch persistent
‘Robinson’	Bud crimson, flowers deep pink, bronze-green foliage	25 feet by 25 feet	Dark red 3/8 inch
‘Royal Raindrops’	Bright pinkish-red, purple cutleaf foliage	20 feet by 15 feet	Red 1/4 inch persistent
‘Sargent Tina’	White, dark green foliage	5 feet by 6 feet	Dark red 1/3 inch persistent. Very small tree
‘Sparkling Sprite’	Pink buds to white, bright green foliage	12 feet by 12 feet	Yellow to golden orange 1/4 inch
Winter Gold	Red, dark green foliage	25 feet by 20 feet	Gold fruit persistent
‘Zumi Calicarpa’	Red bud to white flowers, green leaves	20 feet by 24 feet	Bright red 3/8 inch persistent

 

TABLE 3. Recommended Medium Street Trees.
Medium trees for medium spaces. Growing 30-45 feet at maturity. Minimum growing space of 5 feet from curb to sidewalk.
Common Name	Scientific Name	Dimensions (Tree Height by Canopy Width)	Some Suggested Cultivars and Notes
American hophornbeam	Ostrya virginiana	35 feet by 25 feet
Blackgum	Nyssa sylvatica	40 feet by 25-30 feet	Numerous cultivars, check dimensions
Carolina silverbell	Halesia carolina Halesia carolina monticola	40 feet by 20 feet 40 feet by 25 feet	‘Rosy Ridge’ Mountain Silverbell
Chokecherry ‘Canada Red’	Prunus virginiana	25 feet by 20 feet	‘Canada Red Improved’
European hornbeam	Carpinus betulus	40 feet by 30 feet
Hackberry, columnar	Celtis occidentalis	45 feet by 12 feet	‘Prairie sentinel’, columnar, suitable in rows for formal planting
Imperial Honeylocust	Gleditsa triacanthos	45 feet by 20-35 feet	Check cultivar specifics for size. ‘Impcole’, ‘Streetkeeper’, ‘Skyline’, ‘Shademaster’
Japanese Tree Lilac	Syringa reticulata	30 feet by 25 feet	‘Ivory Silk’
Lavelle Hawthorn	Crataegus x lavellei	30 feet by 25 feet	Fewer thorns than other cultivars, okay if limbed up
Maple cultivars, smaller growing	Acer rubrum	45 feet by 15 feet	‘Armstrong’, ‘Autumn Flame’, ‘Redpointe’, and the like, check cultivar characteristics
Persian parrotia	Parrotia persica	30 feet by 20 feet	Not salt tolerant, plant only on streets that are not treated for snow
Red Horsechestnut	Aesculus x carnea	40 feet by 40 feet	‘Ft. McNair’
Yellowwood	Cladrastis kentuckea	40 feet by 40 feet	Remove lower branches over time as it grows, until clear 6 feet of trunk
Zelkova, select cultivars	Zelkova serrata		‘Village Green’, 40 feet by 40 feet ‘Musashino’, columnar 45 feet by 15 feet

 

TABLE 4. Recommended Large Street Trees.
Large trees for large spaces. Growing 45 feet or more at maturity. Minimum growing space 6 feet from curb to sidewalk.
Common Name	Scientific Name	Dimensions (Tree Height by Canopy Width)	Some Suggested Cultivars and Notes
Basswood cultivars	Tilia Americana Tilia cordata		Check cultivars for dimensions
Elm hybrids	Ulmus x		‘New Harmony’, ‘Princeton’, ‘Patriot’, ‘Morton’, ‘Morton Stalwart’, ‘Morton Red Tip’
Gingko (male only)	Gingko biloba		Not propagated from lateral buds
Hackberry cultivars	Celtis occidentalis		“Magnifica’, ‘Chicagoland’, ‘Prairie Sentinel’
Honeylocust	Gleditsa triacanthos		Check cultivars for dimensions
Red Horsechestnut	Aesculus hippocastanum	50 feet by 40 feet	‘Baumann Double’. Sterile/seedless
Japanese Pagoda Tree	Styphnolobium japonicum (Sophora japonica)	45 feet by 35 feet	‘Millstone’ 45 feet by 35 feet
Kentucky Coffee Tree	Gymnocladus dioica		‘Espresso’
Linden, silver linden	Tilia tomentosa	45 feet by 35 feet	‘Sterling’, ‘Green Mountain’
London Plane Tree	Platanus x acerifolia		‘Exclamation’, ‘Bloodgood’
Sugar maple	Acer saccharum
Oak, Bur	Bur Oak		For large landscape locations only, unless using ‘Urban Pinnacle’, 55 feet by 25 feet columnar - small acorns
Oak, Chestnut	Quercus montana
Oak, Chinkapin	Quercus muehlenbergii
Oak, Northern Red	Quercus rubra
Oak, Shingle	Quercus imbricaria
Oak, Shumard	Quercus shumardii
Oak, Swamp White	Quercus bicolor
Oak, White	Quercus alba
Oak, Willow	Quercus phellos
Osage Orange (male)	Maclura pomifera inerma		‘Whiteshield’
Sweetgum	Liquidambar styraciflua		‘Moraine’, ‘Rotundiloba’
Zelkova	Zelkova serrata		‘Green Vase’, ‘Halka’

 

TABLE 5. Recommended Trees Suitable for Parkway, Parks, Natural Areas
Proposed parkway and development edge trees which are suitable for very large easements or natural areas because of large size, fruit, or characteristics detrimental in street tree locations. Trees from the large and medium street tree lists may also be used as appropriate on large sites to obtain the benefits of a healthy tree canopy.
Common Name	Scientific Name	Dimensions (Tree Height by Canopy Width)	Some Suggested Cultivars and Notes
Bald Cypress	Taxodium distichum	70 feet by 45 feet	Tolerates wet soil
Black Hills Spruce	Picea glauca var. dens	30 - 60 feet by 25 feet	Slow growth
Black Locust	Robinia pseudoacacia	50 feet by 35 feet	In large difficult sites as last resort, far from people or vehicles. Suckers
Bur Oak	Quercus macrocarpa	80 feet by 80 feet	Acorns at maturity (35 years). Tolerates dry soil after established
Cornelian Cherry	Cornus mas	18 feet by 22 feet	Low growing. Wider than tall except for cultivars. Fruit unsuitable for street tree
Dawn Redwood	Metasequoia glyptostroboides	100 feet by 25 feet	Tolerates wet soil. Excellent specimen tree
Goldenrain Tree	Koelreuteria paniculata	30 feet by 30 feet	Parkway tree only
Leyland Cypress	Cupressocyparis leylandii	75 feet by 15 feet	Medium water needed
Norway Spruce	Picea abies	60 feet by 30 feet	Medium water needed
Sargent Crab	Malus sargentii	8 feet by 12 feet	This low-growing crab is low and wide and cannot be limbed up attractively for street use
Shagbark Hickory	Carya ovata	90 feet by 70 feet	Hickory nuts at maturity
Shellbark Hickory	Carya lacinosa	80 feet by 60 feet	Hickory nuts at maturity
Sycamore	Platanus occidentalis	100 feet by 100 feet	Large leaves, exfoliating bark; good wildlife habitat
Tulip Tree	Lirodendron tulipfera	90 feet by 50 feet	Weak wood, place in large open parkway area

 

(Ord. 2019-25, passed on 5-13-2020)