cross-posted from: https://slrpnk.net/post/998526
Shamelessly stolen from u/OccamsLoppers on Reddit.
The idea is that the trees planted will provide benefits that far exceed the costs of pruning or sidewalk repair. These costs can also be minimized with proper species selection, though in my experience HOAs typically lack the expertise to make good decisions on that topic.
This study found that for every dollar spent on tree installation, maintenance, repairs, etc, $5 of public value was returned. Seems like a good investment! https://www.fs.usda.gov/psw/publications/mcpherson/psw_2016_mcpherson004.pdf
Unfortunately, the benefits of trees are often intangible and dispersed across the community, while the costs can be more immediately felt in some cases. Ideally, your town’s urban forestry program should bear these costs so that they can be more evenly distributed like the benefits, but the political environment in some areas does not always allow for enough budget.
How does one determine a good species to plant between the road and the sidewalk? I assume slow growing, do some trees tend to root deep down more than “out” and on the surface which is what damages sidewalks faster?
I hope that someday there will be real data on this issue but right now it’s just anecdotal experience from arborists. There are databases that try to summarize this information. https://selectree.calpoly.edu/ is one I use a lot. California-centric but we have diverse climates so it should be fairly broadly useful. It has a recommended planter width, and ranks trees as high medium or low potential for root damage. Most small trees rarely cause damage, but also provide much less benefit than larger trees. Some bigger species I have noticed rarely lift sidewalks are Chinese pistache (note: invasive in some areas) and bald cypress.
That said, soil is also a large factor here–loose, oxygen rich soils promote deeper rooting and there is a lower likelihood of concrete damage. So proper soil management and protection can have an impact here as well.
This is really interesting, thanks! I had no idea. Our HOA does have a list of approved and disallowed trees but I don’t know the extent of it. Luckily we were able to plant a tree that is local to the area and is a small tree when fully grown. And I do really love that there are lots of trees in the neighborhood.
It’s funny you mention sidewalk repair because I feel like I’ve ever only seen that in one place I’ve lived. Highly anecdotal, I know. Hopefully in several years when the trees are more mature and the sidewalk has issues, the city will fix it.
Unfortunately, that sounds like more of an issue of bad governance than a tree problem per se. Sidewalks and other infrastructure can be damaged various ways, not just by trees, so if the local government is not repairing it then it will become a problem eventually. Keep in mind that many municipalities operate more based off of complaints than providing an even level of service everywhere. So if you are having a problem you may need to complain to get it fixed.