|Local Tree Info|
|Tree Planting Programs|
Portland's Recommended Tree List:
Trees on our recommended list represent varieties that have shown hardiness to our Portland, Maine climate, display favorable characteristics and are generally available in the nursery trade. Co-Op Nurseries offer a wide selection of shade and ornamental trees, including trees native to New England along with interesting non-native ‘exotics’. Trees with * are readily available and especially recommended.
Trees are grouped into the following categories: "Street trees" (ST) which are trees recommend for planting between the sidewalk and street, or along street lines due to desired characteristics such as branching height, shape and hardiness to grow in urban conditions. Street-trees tend to include more ‘shade trees’ that are grown for shade vs. ornamental qualities. "Lawn trees" (L) are ‘setback’, planted away from the esplanade or street on the lawn area. They can be multi-stemmed or lower branched than the street-trees and may be less tolerant of urban conditions. "Lawn trees" include: ‘shade’, ‘ornamental’ and ‘conifers’.
It is important to match the desired characteristics of the tree to the site where the tree is intended to grow. ‘Plant the right tree - in the right place’. Shade, screening, ornamental qualities such as flowers, fruit, or interesting bark, how big will the tree grow and where will it grow best? What are the site conditions - wet or dry, sun or shade? Trees need room to grow, picture the mature tree size growing in the location you plant to plant the new tree. See updated USDA Plant Hardiness Map: http://planthardiness.ars.usda.gov/PHZMWeb/#
Planting Site Guidelines -
Trees planted in sidewalk ‘treewells’ have a minimum width of 3.5’ / leaving 3’ for wheelchair and pedestrian travelway. In restricted areas we recommend ‘setback’ tree planting behind the sidewalk. Trees must be set planted 10’ from intersections, driveways, walks, utility poles and fire hydrants.
Tree Planting Web site links -
Please review the following web sites for more information:
ISA – International Society of Arboriculture ‘Trees Are Good’
For info on how to select a tree - http://www.treesaregood.org/treecare/tree_selection.aspx
Also thinking ahead to avoid utility line conflicts:
National Arborday Foundation: ‘Right tree for the right place’ www.arborday.org/trees/rightTreeAndPlace/index.cfm
Cornell University ‘Urban Horticulture Institute’ tree selections www.hort.cornell.edu/uhi/outreach/recurbtree/index.html
UConn: Plant Database www.hort.uconn.edu/Plants
US National Arboretum http://www.usna.usda.gov/Newintro/awards.html
Cary Award Trees / Shrubs http://www.caryaward.org/pastwinners.html\
Tree Size Recommendations 1.75” - 2.5" caliper, or thickness of the trunk at the base, for street-tree planting and 1.5” - 2" for lawn planting. Maximum sizes -3" caliper for shade and ornamental trees and 6-7’ Height for conifers. Co-Op Program limits trees to: 3" caliper for shade and ornamental trees and 6-7’ Height for conifers.
THE TREES ON THIS LIST HAVE BEEN EVALUATED FOR THE FOLLOWING CRITERIA:
|Trees that are readily available and are especially recommended.|
Recommended for Street-tree planting in esplanades, between the sidewalk and the street, or along street lines for their ability to grow in urban conditions. Shade trees and ornamental trees are in this group.
Shade, ornamental, or conifer with single or multiple stem or trunks, low-branched or small tree forms recommended for Lawn planting, set back away from the roadway.
Trees are listed by both Common Name and Scientific or Botanical name.
Small Trees 15’ – 25’
Small trees are often planted along streets under overhead utility lines and for restricted space where a smaller tree is desired, this group offer many ornamental characteristics such as flowers and fruit.
Hedge Maple*, Acer campestre*
Uses: ST / L
Grows slowly to a height of 25’ to 30’ according to reference materials, however, we have several trees that after 20 years are just approaching 15’ in height.
Acer griseum Uses: LAWN AREAS only.
A small specimen tree with interesting exfoliating bark and good fall color, planted in lawn areas only, hard to find, may want to use a smaller size. Beautiful small specimen tree. Grows best in sheltered areas. See at Longfellow Arboretum in Payson Park.
Rocky Mtn. Glow,
Acer gradidentatumn Uses: ST / L
Western Sugar or Canyon Maple – Slow growing & smaller in size then native Sugar Maple grows up to 25’ with round to oval shape. As with Sugar Maples we advise not to plant near areas that use high amounts of de-icing salts in winter. See: www.jfschmidt.com/pdfs/rockymtnglowmaple.pdf
Three-flowered Maple, Acer triflorum
Uses: ST / L
A unique small specimen tree, nice exfoliating bark, tri-foliate leaves that turn yellowish red fall color. See at Longfellow Arboretum in Payson Park.
Korean Maple, Acer sieboldianum
Uses: LAWN AREAS only.
Small maple with good fall color, trees are often multi-stem & low branched.
Amelanchier tree form, Uses: LAWN AREAS only.
Native tree with white or pink flowers in the spring. Available with single (ST) or multi-stemmed (L) trunks and is best used in moist areas with light shade. Not for dry compacted spaces, better for lawn areas than small tree-lawn spaces between the sidewalk and street. ‘Cumulus’ is a single-stem tree form with white flowers, ‘Robin Hill’ is single-stem with pink flowers. Good alternative to ‘Callery’ or Bradford Pear.
Uses: L / ST
Flowers in June and is noted for its red berries in the winter. There are many interesting varieties including: ‘Winter King’ (Lawns), ‘‘Crusgalli’ (Thorn-less) (Lawns & wide esplanades). Crusgali has glossy foliage and is hardy in dry locations.
Flowering Crabapple, Malus
Uses: L / ST
There are many varieties with different attributes of shape, flower, foliage, and fruit. Our favorite varieties include: ‘Adirondack’, ‘Spring Snow’ (fruitless), ‘Snowdrift’ (ST,L), and ‘Harvest Gold’ (L), ‘Donald Wyman’, and ‘Sargent’ for lawn areas and (L) ‘Pinkspire’ and ‘Sentinel’ for narrow sites. Crabapple varieties with larger fruit are not recommended.
Uses: Lawn areas only.
Used as specimens and planted in lawn areas only. ‘Centennial’ and ‘Dr. Merrill’ are recommended cultivars. ‘Leonard Messel’ offers a pink flower. Many more cultivars are now available, check with your Co-op Nursery for availability.
Prunus Uses: L / ST
One of the first flowering trees in the spring. ‘Accolade’ (ST,L); 'Amur chokecherry’ (L) has pink/white flowers and interesting bark, for lawn areas only.
Tree Lilac *, Syringa
reticulate Uses: L / ST
Tree form lilac with white flowers. Available with single (ST) and multi- stem trunks (L), Tree lilacs have performed well as street-trees under utility lines in areas. Requires ample, non-compacted, growing space.
The following small trees are great as non-street trees or lawn area :
Cornus kousa Lawn areas only.
Kousa and the new Rutgers Hybrids, C. kousa x C. florida, are recommended specimen trees for lawn areas, white or pink flowers.
Chionanthus Lawn areas only.
Beautiful small tree with white flowers in June. Available as a multi-stem shrub form.
American Hophornbeam, Ostrya
virginiana Uses: Lawn areas, Native to Maine.
Native tree with interesting bark, lawn areas, does not grow too large, tolerates shade, ‘understory’ tree.
Oxydendrum arboreum Lawn areas only.
Excellent small specimen tree with late summer bloom. Truly, a great small tree for late summer and early Fall bloom & great Fall color. Scarce, available in small sizes.
Stewartia pseudocamellia and koreana Lawn
Flowers in July and has beautiful exfoliating bark. Longfellow Arboretum in Payson Park has a beautiful specimen planted in 1976.
Medium Sized Trees 25’ - 45’
Betula nigra Uses: Lawn or
landscape areas only.
Fast growing birch with creamy white to brownish bark. River Birch have fewer insect & disease problems than the Paper Birch. See grove of River Birch at the Longfellow Arboretum along the Payson Park roadway.
or European Hornbeam* Carpinus caroliniana & Carpinus betulus,
A nice small to medium sized, compact tree in single-stemmed (ST) and multi-stemmed (L) forms. The bark and leaves are similar to beech trees. Upright forms are useful for screening or hedges. Hornbeam makes an excellent screen, does best in non-compacted lawn areas vs. tree well situations.
Cercidiphyllum Uses: Lawn areas.
This is a unique tree with heart shaped leaves that open as reddish purple, turn green, with yellow-orange Fall color. This interesting tree can be seen at the Longfellow Arboretum in Payson Park.
Cladrastis Uses: Lawn / Street-tree with ample room.
Compound leaves and white flowers blossoming bi-yearly in June. Locations - Deering Oaks Park, State Street at Park Avenue on the left.
Corylus colurna Uses: Street-tree.
We have been planting Filbert’s for over 10 years with good results. It’s hardy, has interesting light colored, rough bark and should grow to 35’.
Thornless honeylocusts have small compound leaves that cast a light filtered shade. Honeylocusts are medium sized trees in Maine and are able to grow in difficult sites. Some recommended varieties include ‘Skyline’ and ‘Halka.’ Honeylocusts due to there branching habit can often be planted under or closer to utility lines than most medium or large trees with necessary pruning.
Tupelo*, Nyssa sylvatica
Native, rare shade tree that can tolerate damp sites and is slow growing after transplanting. Fall foliage is right red. Maine’s largest is near O’Donal’s Nurseries. Ferry Beach State Park in Saco has a beautiful stand of Tupelo.
Sorbus alnifolia Uses: Lawn areas,
This is a beautiful tree which has a different appearance than the common European Mountainash. The Korean Mountainash has beech-like foliage and bark, white flowers in June, and pinkish-red berries in fall and winter.
Large Trees 50’ +
Large trees should not be planted under or close to utility lines.
Uses: Lawn / Street-tree.
Native maple with red leaves in the fall. It tolerates wet sites and is more salt-tolerant than Sugar Maples. There are many new cultivars and Red Maple / Silver Maple hybrids.
- upright cultivar seen in the Old Port area.
‘Karpick’ Red Maple* - more open with a upright / oval form.
‘Autumn Blaze’ Red Maple* – larger, fast growing hybrid with great Fall color.
saccharum Uses: Lawn area.
Native maple with yellow-orange fall foliage. Upright cultivars are available for narrow spaces. Not salt tolerant. See ‘Rocky Mtn Glow’ Sugar Maple for smaller landscapes in the Small Tree section.
Catalpa Uses: Lawn area.
White flowers bloom in June and seedpods develop in the Fall. Interesting Winter form.
Fagus Uses: Lawn area.
American and European varieties. There are many leaf shapes with color ranging from green to purple. Standard beeches are best planted in lawn areas or behind sidewalks because it needs some room to grow. We have seen upright varieties as successful street trees in the Western Prom area. Many interesting cultivars exist, including ‘Riversi’ that has purple leaves, and ‘Aspenifolia’ that has fern-like leaves.
Fraxinus americana (White) & pennsylvanica (Green) Uses: ST
Green and White Ash are large, fast growing shade trees. The Green Ash is more common and has bright yellow fall foliage. Varieties include ‘Summit’ and ‘Patmore.’ The White Ash varieties ‘Autumn Purple’ and ‘Empire’, is a new upright selection. ‘Leprechaun’ Ash* is a small 15’ round shaped tree for smaller areas. (Emerald Ash Borer is a serious potential threat to Ash trees, not in Maine, yet.)
Ginkgo, Ginkgo biloba
Uses: ST / L
A truly unique tree with fan-shaped leaves and an interesting history. Ginkgos are slow growing after transplanting, but grow well in difficult sites. Cultivars: ‘Autumn Gold*’ – broad, conical form with good Fall color, ‘Magyar’ upright form.
Tulip shaped leaves with an interesting flower blooming at the top of the tree. Large, fast growing tree that needs room, interesting tree. Maine’s largest Tuliptree is on Munjoy Hill.
Magnolia acuminata Uses: Lawn
A large shade-tree magnolia that does not have the showy spring flowers of other Magnolias. It is an interesting tree, A beautiful specimen is on Brackett Street at Walker Street.
(Street trees only where ample planting space exists) There are many varieties of native oak including the common Red Oak, Pin Oak, Chestnut Oak*, White Oak, and Swamp White Oak*. These long-lived, big trees need room to grow but are one of the best native trees. The Swamp White Oak has beautiful glossy foliage and exfoliating bark. Pin Oaks are easily established. Two forms of English Oak, Quercus robur, ‘Skymaster*’ (pyramidal) and ‘Skyrocket*’ (columnar) can be planted in more restrictive areas including as ‘street-trees’.
Ulmus (ST,L) American Elm, Chinese or Lacebark Elm,
Once the most popular of all trees, Dutch Elm Disease (DED)has caused and continues to be a severe problem. New resistant varieties have shown promise in resistance to DED, ‘Patriot’, ‘Princeton’, ‘Pioneer’, and ‘Lacebark’ Ulmus parvifolia. Limited availability. Fast growing.
(ST,L) (ST,L) Medium to Large tree,
A vase shaped tree that was hoped to replace the American Elm…Zelkovas are vase-shaped but smaller than elms. Difficult branching angles can cause some problems later on if not pruned correctly. Many beautiful specimens exist in the West End near Danforth Street.
Conifers & Evergreens -
For lawn planting only!
Conifers & evergreens are a great addition to the landscape. In the past conifer planting was often limited to planting a small Blue Spruce or rows of White Pine. Note – many evergreens can quickly outgrow a small space, take time to review growth rate and size. Nurseries now offer many new sellections with many sizes and shapes. We recommend the following:
Swiss Stone(*) Pinus cembra, small, (30’) slow growing with soft blue green needles. See nice specimen at the Spring Point Shoreway Arboretum in South Portland. Others: ‘Vanderwolf’(*) Pine, p. flexlis, very narrow, upright with soft blue-green needles.
Serbian(*) (good upright form), Norway Spruce offers pendulous branching, White Spruce is a good ‘native’ spruce. Serbian Spruce is not as wide, and is better for lawn areas. Blue Spruce often suffer from insect problems and out-grow their site. Oriental Spruce is a variety that has become more available showing good characteristics.
Concolor Fir*, Balsam and Frasier Firs are used as Christmas trees. Moderate growth rate and large mature size.
Concolor Fir has great soft blue-green foliage, see nice specimen in Deering Oaks Park near the Rose Circle.
Offer the shape and screening of an evergreen, but during the winter months allow sunlight. TYPES: (Lawn use only) Dawn Redwood or Metasequoia*, Baldcypress, Taxodium distichum, and Japanese Larch, Larix kaempferi*, are three underused and beautiful deciduous conifers, consider them as ‘evergreens’ that loose their needles. Great for lawn areas, naturalized or as specimens, they have the advantage of allowing winter sun as they drop their needles in the Fall with great fall color and texture.
NOTE - Portland, Maine is located in USDA Plant Hardiness Zone 5 B
Co-Op Nurseries: Trees must be selected from one of the following nurseries:
O’Donal’s Nurseries in Gorham 839-4262 www.odonalsnurseries.com
Skillin’s Nurseries in Falmouth 781-3860 www.skillins.com
Risbara’s Greenhouse in Portland 797-0066 www.risbarasgreenhouse.com