The Urban Tree Canopy: How Trees in Cities Keep Temperatures Low

So today we're talking about urban tree canopies.

So what is an urban tree canopy?

It's really, simply put, it's all of the trees in a community.

So we might think about all the public trees, you know, the parks and the boulevards and the street trees that are out there.

But it's more than that.

It includes all of the trees in the commercial areas and all of the trees in everybody's backyard.

So if we think of that all together as a forest, but in the middle of a community, that's our urban tree canopy.

So what is the function that a canopy provides to the community?

So there are, and here I might get in trouble.

You might have to cut me off because I will talk about the benefits of trees and shrubs and plants all day long, following people out to their cars after the class is over.

Roughly, we can categorize the benefits into a few different things.

There's the health and wellness benefits to people, to humans.

There are the economic benefits to commerce.

Really, I think what we gardeners think of are the environmental services that they provide.

Trees in a community are a lot like trees in your backyard.

You have shade in your backyard, but if you have a lot of trees in a community, you have the accumulation of the cooling that provides If you think about a tree in your backyard buffering sound or providing a little bit of a sound break, a lot of trees in a community also provide a sense of privacy and maybe deadening some of the noise in the area.

There are some other benefits like tree-lined streets tend to slow drivers down and so Sometimes you will even see trees intentionally planted around schools so that people will naturally slow down.

I mean, they hopefully are anyway, but where there are trees, people will kind of subconsciously think, I'm not sure if I have all the visibility I need.

Maybe I should slow down.

And yes, you should probably.

Some of the really big benefits are that a lot of trees in our community do a good job of intercepting air pollution, different types of air pollution.

One of the ones they do a really good job of intercepting are what we call particulate matter.

So dust, pollen, mold spores, things like that, that are fairly large, and they do a good job of just acting like, well, acting a little bit like my bookcase, right? Every time I go to my bookcase, I don't know where all that dust came from, but somehow the dust just shows up there.

Trees and, to a lesser extent, shrubs are like that a little bit.

So they're cleaning the air.