People and trees do not get along. Sure, we like to swing from their branches, relax in their shade and decorate them with lights and ornaments, but the level of abuse trees take from mankind is and intense and getting worse. The abuse comes in the form of pollution both in the air and in the soil, two areas crucial to a tree's existence. The math is simple: the more people around, the harder it is for a tree to prosper. City dwellers need to consider a tree's hardiness when selecting which is best to plant in an urban environment. Other concerns include root growth, as an aggressive shallow-rooting tree can tear up sidewalks and foundations.
Siberian Larch (Larix sibirica)
The Siberian Larch, sometimes called the Russian Larch, is a tall, pyramid-shaped coniferous tree with branches that spread laterally. The needles are green but turn yellow and ultimately drop in the fall. The Siberian Larch enjoys cold weather and thrives well in northern climates. This tress is a bit of a loner, as it is intolerant of shade from neighboring trees.
Sugar Maple (Acer saccharum)
The Sugar Maple, best loved for its beauty, vibrant foliage, and its sap (used to produce maple syrup), is a northern climate tree that thrives in the wild or in the city. Common to Michigan, New York, Maine, Wisconsin, and Pennsylvania, maples are excellent city trees. David Nowak, a forestry researcher with the U.S. Forest Service's Northeast Research Station, recommends planting maples as a means to fight off greenhouse gases. Aside from absorbing several tons of carbon dioxide each year, the maple's low-maintenance status reduces fossil fuels often required to grow a tree (water trucks, pruning, pest control, etc.). In addition, when the fall comes and the sap runs, there is nothing quite like the beauty of a maple just before the leaves drop.
Pecan Tree (Carya illinoinensis)
Native to North America and a source of great pride in Texas (where it is the state tree), the pecan tree is a city favorite due to its size and durability. Found in parks, a mature pecan can grow 100 feet tall. Not actually a nut, the pecan is a fruit which splits open when mature to reveal the inner stone or pit. This pit is the pecan nut we enjoy caramelized, salted, or in pies. This is another low-maintenance tree that lives for as long as 300 years.
American Sycamore (Platanus occidentalis)
The American Sycamore is a tall, narrow tree that tends to show the most growth in summer and spring. With broad green leaves, the American Sycamore is an attractive addition to a backyard or for planting near a home or building. The sycamore requires very little by way of human attention other than water. The tree is easy to find at a building center garden department and is easy to transport and plant. In just a few years, a sapling American Sycamore will be as tall as a two-story home.
White Alder (Alnus rhombifolia)
A member of the birch family, White Alder is a fast-growing and attractive tree that can reach heights of 100 feet tall. This attractive backyard tree will form a deep dark green canopy of small leaves that stay on the branches most of the year. A California native, the alder will thrive in USDA Hardiness Zones 6 to 10. The White Alder is not particularly drought-resistant and tends to pop up in the wild near a stream or riverbank.
Liquid Amber (Liquidambar styraciflua)
Southern Californians longing for the autumnal colors from back east should consider the Liquid Amber tree. The leaves of this narrow, green-canopied tree turn a dark shade of red in fall, but unlike northeastern trees, the liquid amber holds its leaves well into the winter. The tree will survive even in the harshest city environment and should be placed near available water. This tree is terrific in a boggy area.
One of the most attractive trees in the southwest, it does has two drawbacks. The seedpods are round, spiny fruits that drop in the fall and make for extra gardening work. The tree also has an aggressive root system. Do not plant this tree near a home or a sidewalk.