Selection in the City.

Background

Baltimore City has committed to increasing its canopy in an effort to combat climate change and the urban heat island effect. Current efforts are focusing on historically red-lined and marginalized neighborhoods that tend to lack large, old growth trees. However, research has shown that trees purchased and planted by city organizations lack diversity. Often, we see the same few species of trees planted in mass.

A Tree is a Tree

Why do we care if there is limited species diversity? If trees are good for the environment, does it matter what species we plant? These are questions I get asked a lot by community members. To answer this, I remind people of all of the trees lost to Dutch Elm Disease, American Chestnut blight, and more recently, the Emerald Ash Borer. Diseases that target a specific species tend to be deadly. If such a disease were to affect a commonly planted tree, it could result in a large loss of current canopy and loss of millions of dollars invested in tree planting efforts.

The Popular Trees

Red Maple is one of the mostly commonly planted trees in Baltimore City. It is native to the eastern United States tolerates a wide range of environmental conditions. It is a hardy tree that is able to survive many of the stresses of city life, such as compacted soils, air pollution, and dry conditions. It is a favorite among landscapers and planters for its resilience and beauty.

Norway Maple is native to Europe and Western Asia. Introduced in the 1700’s, it is now considered invasive. Its large broad leaves provide dense shade, making it an excellent candidate for an urban shade tree. Like red maple, Norway maple is also versatile and resilient.

Among planted trees in streets, parks, and residential yards, we find that red maple is the number 1 most commonly planted tree and Norway maple is the number 7th most common.

Norway Maple | Acer platanoides