Where to plant trees to best benefit the urban landscape
You may not be aware but when you plant a tree or water and maintain the ones you have, you not only add cultural value (appearance, shade for sitting in the yard) to the city but you also are planting an air cleaner and a heat reducer which provides billions of dollars in pollution management services. Looking at the bigger picture, that’s what the city forestry office does but on a much wider scale. For example, tree planting in Denver stresses planting trees on the west side of properties because that does the most to reduce heat islands, which are defined as hotter than average areas in a city caused by the reflection of heat by pavement and buildings.
Cities even have ordinances that protect the urban canopy. Cities and HOA’s usually must replace a tree that it removes and it’s these air purifying and heat reducing features which they are leveraging to improve quality of life.
While a study of trees in Baltimore, MD failed to uncover anything that an arborist might consider new, it was useful data in explaining to politicians and neighborhood leaders why the city’s tree planting needed to be increased. They got the added budget. Here are some other considerations to where to best plant a tree.
First, look up. If you see obstacles. Especially power-lines, that might not be the best place since the tree will likely grow into the wires creating a potential for outages and certainly making it much more expensive to trim or remove.
Look down. Areas where water pools or areas that are always dry or get a lot of sun or very little sun, may also not be the best place to plant.
Look to the side. Will the tree block right of way and sightlines. That’s pretty easy in your own yard. For city foresters it can be a little more difficult.
For city planners, some of the best areas to plant trees to mitigate heat index rises are by their nature impossible to plant tree. No one in their right mind would suggest tearing up a parking lot or removing a building, because they are optimal places to plant trees. However using sophisticated data packages such as I-Tree https://www.itreetools.org/,cities can easily plan to plant trees in areas with available soil while providing maximal benefits to the tree canopy at large.
Finally, it’s good to avoid certain species such as ash which are threatened by EAB and black walnut ( which are susceptible to 1000 canker) and also avoid weak – limbed trees such as cottonwoods, which are more likely to become hazard trees.