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Plant Focus
Urban Oak Landscapes of the Future
Bryan R. Denig, Miles Schwartz Sax, and Nina L. Bassuk
Published May 2019 in International Oaks No. 30: 247–252
Abstract
What role will oaks play in the urban landscapes of the future? Currently, over half of the global human population lives in urban areas, and some projections anticipate that this will increase to two thirds by 2050. Trees are vital to enhancing the quality of life in cities, as they provide many environmental, economic, and sociocultural benefits. Yet to provide these benefits in a substantial way, urban trees need to grow well and survive for long periods. Unfortunately, trees surrounded by pavement are usually short-lived. Some studies have found the average lifespan of city street-trees to be as low as 10 years. Elevated temperatures, drought, and degraded soils are just a few of the reasons for their early demise. These challenges have led to a diversification of the trees planted in cities, yet the species utilized should still be tolerant of stressful urban conditions. Matching a tree species to the environment of the planting site is key to success. As a genus, Quercus is often underrepresented in cities (at least in the Northeastern United States). When oaks do compose a considerable proportion of the urban forest, it is usually only with a few species of Quercus. This is surprising, as the genus is so large and diverse, and oaks in general often have the reputation of being stress-tolerant. So why aren’t oaks better represented in urban tree plantings? And how can quercophiles encourage the greater use of oaks in future urban landscapes?
Keywords
climate change, urban forestry, street trees, species diversity
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