Recommended Shade Trees

The following trees are recommended for urban and suburban street planting. 

Category I Trees

The trees in Category I represent those which most often mature to approximately 30’ or less in height. The more confined growth habit of category I trees frequently allows them to be considered for locations beneath utility wires and other similarly restricted planting areas.

Category II Tree Selections

The trees in category ii represent those which most often mature to approximately 30’ or more in height.  Category II trees are normally medium to large in size and are most suitable where overhead utility wires are not present.

Oaks which may be potentially be considered as street trees include:

Resources

It should be noted that Recommended Urban Trees: Site Assessment and Tree Selections for Stress Tolerance was used as a general guide in compiling the Borough of Media’s “List of Recommended Street Trees”.  This 122-page document was published by the Urban Horticulture Institute of Cornell University.

A few additional urban/street tree publications were also consulted including:

1. the Delaware Center for Horticulture,
2. West Virginia Division of Urban & Community Forestry (West Virginia University Extension Service),
3. Urban & Community Delaware Forest Service,
4. New York State Urban Forestry Council, (5) New York City Parks Department, and the
5. Delaware Forest Service. 

In addition, the Urban Tree Selection Guide as published by Casey Trees was reviewed.

Additional Notes

What criteria(s) are used to judge the suitability of various tree selections for street tree use?  

It should first be noted that cultivar selections often significantly improve and extend the landscape value of trees for ornamental use.  

Cultivars are asexually propagated and are routinely introduced into the trade based on any number of superior traits---often allied within a broad range of categories. A small sampling of these characteristics may include:

1. improved resistance to harmful diseases or insects,
2. positive differences in forms, shapes or habits,
3. more desirable fruitless and/or thornless features,
4. improved cold-hardiness,
5. improved heat tolerance,
6. increased proficiency of bloom size,
7. increase in the quantity and/or quality of floral production,
8. extended range or floral colors and/or fragrances,
9. increased fruit quantity and/or quality, and
10. improved fall foliage color.   

Please note that no crabapple (Malus sp.) or Hawthorn (Crataegus sp.) cultivars are included in this list. Crabapples are primarily introduced for their prodigious quantities of bright and showy fruit. Most Hawthorns boast a large number of fruit---along with sharp and prominent thorns. Although numerous Crabapple and Hawthorn cultivars can make excellent additions to the home landscape, they are not especially well-suited for use as street trees.

Moreover, it is imperative to only select Crabapple cultivars which are acceptably resistant to a wide and diverse range of plant diseases, with particular emphasis towards Cedar-Apple Rust, Mildew, Apple Scab and Fireblight.

The Chinese Chestnut (Castanea mollissima) offers an array of favorable landscape features---but produces sizable crops of nuts which are encased in large and sharply spined outer coverings.

Unfortunately, it is not unusual for a single negative quality to entirely negate the use of a particular species for street tree use.  

In like manner, the Northern Catalpa (Catalpa speciosa) produces long and slender 12” to 18” pods which remain on the tree well into the winter months. The length of the pods and the length of time they remain on the tree are both characteristics which make the Northern Catalpa an unacceptable choice for street tree use.

In other situations, closely related trees, can in certain situations offer little if any practical advantage over their close relatives---particularly if such secondary selections are much more difficult to locate within the trade. 

The Amelanchiers sp. are a prime example.

Other species make fine street trees but are extremely difficult to locate in sufficient sizes and/or quantities. 

The Persian Parrotia (Parrotia persica) is a very uncommon commodity within the nursery trade. 

Both the Hardy Rubber Tree (Eucommia ulmoides) and the Dove Tree (Davidia involucrata) easily fall into this same category of limited availability. 

Some species can be somewhat of a “judgement call” regarding their suitability for street tree use. 

One such example is the Flowering Dogwood (Cornus florida). The Flowering Dogwood is an extremely beautiful small-flowering tree, which hosts an abundance of large and showy flowers (more properly termed: bracts). The Flowering Dogwood is easily recognized and identifiable even from a distance. 

What borough or township would not appreciate a showy assemblage of Flowering Dogwoods? 

The issue is that the Flowering Dogwood is host to a sizable number of insect and disease problems---and is especially prone to borers. 

On a related note, the Birches (Betula sp.) can likewise be prone to their share of insect and disease issues. Sold and purchased almost exclusively as multi-clump specimens, they can offer a majestic ambience to most any home landscape.

Although the River Birch (Betula nigra) is a particularly valued ornamental, its multi-stem form negates its use as a street tree. Its best application within a municipal setting is to be potentially utilized in raised planter beds and similar low-impact environments.

In a somewhat related circumstance, the Goldenchain Tree (Laburnum x watereri) is an exceptional small-flowering ornamental. However, it has limited use as a street tree due to a diminutive mature height of only 12’ to 15’.

Finally, a select number of magnolias can in special situations be considered for street tree plantings. One problem with certain magnolia cultivars is that they frequently mature to overly broad proportions and not uncommonly can grow as wide if not wider than they grow tall. The oft-used Saucer Magnolia often grows to approximately 30’ in height---but often with an equal if not wider, horizontal spread.

Three magnolias to be potentially considered include the Merrill Magnolia (Magnolia x loebneri ‘Merrill’), the Star Magnolia (M. stellata) and the Kobus Magnolia (M. kobus). If a reasonably small, early spring blooming tree with prodigious white floral displays is desired---these three magnolias are hard to overlook.     

In conclusion, there are an especially broad array of important characteristics to be considered when choosing a tree for street tree use. No two planting sites between the sidewalk and the curb are exactly the same and by the same token there is no such thing as a perfect street tree.

Thank you,

Media Borough Shade Tree Committee