Cities are vulnerable to heatwaves. But green spaces can help more than we thought

[Nouvellecosse]

Originally Posted by edale

Of course trees provide shade and cool the urban environment, but I struggle a bit with desires to have extensive tree cover in climates that don't naturally support forests. I see this in the Los Angeles area all the time, where neighborhood groups and tree enthusiasts are always advocating for more and more trees to be planted in public right of ways, trees retained on private property, etc. Historically, Los Angeles was not a tree covered place (in the mountains and along natural waterways, yes, otherwise, no), and we don't get the year round water required to keep trees healthy throughout the year. Yet that doesn't stop people from wanting their neighborhoods to look like Atlanta.

You move to a place because it's warm and sunny 9 months a year, but you also want a lush, shady, forested environment? For some reason, this just really bothers me. Don't move to a semi-arid climate and expect to live in a shady forest. In drier climates, I think cities should try to promote shade structures, awnings, colonnades, etc. rather than create artificial forests that require irrigation.

Well that's the crux of it. A lot of the areas that don't naturally support trees also don't "naturally support" large human cities either. So whether or not its "natural" in the environment isn't really any more important than whether or not the streets, sidewalks, buildings, and infrastructure are "natural." The trees (or other environmental elements like plants, certain animals, and geographic forms) can basically just serve as a form of infrastructure. It's what we in the planning field refer to as ecosystem services which can be used to achieve goals and provide benefits that people want. Such services may or may not be "naturally occurring". The important thing is really just whether or not we could accomplish the same goals as efficiently and effectively through other methods. But ultimately, if a landscape is too inhospitable to humans then there may not be any good options.

[wwmiv]

Literally, one of the essential ingredients to support a large human population IS an extensive tree canopy. No matter your skin color, they protect against the harsh environment of being exposed to the sun for long periods of time—exposure which none of us is evolved to handle. Hence why we live in houses, work indoors, commute in cars, and stay out of the sun even when we are outside unless we are a member of the lowest discriminated against classes or castes who are horribly forced into unnatural conditions like extensive sun exposure through work, life, homelessness, or other circumstance. It isn’t that it’s natural… it’s that our society doesn’t /care/ that it isn’t natural and isn’t taking adequate steps to fix the lack of tree cover in many of our major cities. There are other biological effects, of course, such as air quality. There are also psychological benefits to an extensive canopy, insofar as they make us feel safe (because a forest is the environment in which our brains likely largely evolved).

The big trade-off, of course, is the ground water and/or imported or captured water supply necessary to maintain a large tree canopy and in what other ways that water could be used (or the money that was used to capture it or import it otherwise spent on whatever other priorities).

[JManc]

Originally Posted by craigs

Trees make more sense in places like Los Angeles than green grass lawns. The region would be better off if people stopped watering lawns and shifted to watering shade trees instead.

Lawns are a massive waste of money and water. I would convert ours to native plants and grasses in a NY minute if the HOA's weren't hung up on having a manicured lawn. The drought last summer killed most lawns and they still haven't recovered. Looks like a typical California lawn with yellow dead grass and everywhere.

[Steely Dan]

Originally Posted by JManc

Lawns are a massive waste of money and water.

The small lawn in front of our building costs zero money or water (other than the water mother nature rains down upon it).

Lawns that people insist on being bright kelley green 24/7/365, as though they lived in some damp Irish countryside sheep's meadow where it never stops misting, do require a lot of extra water in most places, but it does not harm your grass if it yellows out during periods of no rain.

Whenever it next rains again, it bounces right back.

Plus, not only is it eco-friendly to just leave your lawn the fuck alone, it's also means you don't gotta do anything!!

Lazy lawn care is best lawn care.

[Wigs]

Originally Posted by JManc

Lawns are a massive waste of money and water. I would convert ours to native plants and grasses in a NY minute if the HOA's weren't hung up on having a manicured lawn. The drought last summer killed most lawns and they still haven't recovered. Looks like a typical California lawn with yellow dead grass and everywhere.

Americans love of private property but also love of Homeowners Associations does not compute to me as a Canuck.

"I love my house but then pay a fee for the privilege of being part of a neighborhood association where my neighbors get to dictate what I can and cannot do to MY house and MY property"

[Wigs]

hhnc, I keep tabs on Kansas City because I like following their streetcar expansion and overall development/redevelopment.

KC has a plan to plant 10,000 trees in 3 years.

This year the USDA Forest Service gave the city a $12M grant towards their efforts
https://www.kcmo.gov/city-hall/depar...ces/free-trees

https://www.kcmo.gov/Home/Components...News/2083/1746

The city of Kansas City recently expanded its Canopy Cover KC program to plant 10,000 trees in 3 years.

The city calculated that trees could provide more than $28 million savings in stormwater management, energy reduction, and air pollution control.

https://greenabilitymagazine.com/get...tion%20control.

Short video from 2023 where the city of Kansas City gave away almost 1,500 trees, and planted 1,500 more
• Video Link

[JManc]

Originally Posted by Wigs

Americans love of private property but also love of Homeowners Associations does not compute to me as a Canuck.

"I love my house but then pay a fee for the privilege of being part of a neighborhood association where my neighbors get to dictate what I can and cannot do to MY house and MY property"

It's common in newer master planned subdivisions in the sunbelt and for the most part, they are fine. Ours has very few restrictions (almost too few). We own a townhouse where the HOA is run by a bunch of Karens who send nasty grams if our tenant leaves the garden hose by the front door. We can't wait to sell that place...

[3rd&Brown]

Originally Posted by Wigs

Americans love of private property but also love of Homeowners Associations does not compute to me as a Canuck.

"I love my house but then pay a fee for the privilege of being part of a neighborhood association where my neighbors get to dictate what I can and cannot do to MY house and MY property"

I live in an HOA for the first time of my adult life. It's not so bad. It can go overboard (I left a trash can out for a day too long when I was traveling for work...and got a notice to "cure" the condition) but all in all I like the guarantee that I'm not gonna live 3 doors down from someone that isn't going to maintain their property at all. There's nothing more demoralizing than having a nearby neighbor that doesn't maintain their property and having to look at it day in and day out.

[cabasse]

Originally Posted by JManc

It's common in newer master planned subdivisions in the sunbelt and for the most part, they are fine. Ours has very few restrictions (almost too few). We own a townhouse where the HOA is run by a bunch of Karens who send nasty grams if our tenant leaves the garden hose by the front door. We can't wait to sell that place...

this is one of the main reasons we sold our townhouse and moved into a SFH. my husband joined the board at the last place (and here in the new one as well) - we'd gone through the process to get a quote for solar there, put in a request to get it approved and at the last minute it was denied by one stubborn member.

funny enough, the community we're in now is more older folks, but they seem much more laid back. they are perfectly fine with the idea here, so it's one of those things on the list of to do's in the coming months...

[jmecklenborg]

Originally Posted by hauntedheadnc

You don't say? Well, I can't imagine why someone would have taken the time to study something so obvious, and come up with an actual temperature range -- seems like a dreadful waste of time to know exactly how much a street tree can affect the temperature of the surrounding area.

Many US cities have woods and big trees all over the place, and not as part of some plan endorsed by Twitter or wherever this article came from. Trees aren't a new idea.

Also, many poor Americans don't understand nutrition/hydration and refuse to drink water and/or electrolytes while working in the heat or while just sitting around. You can't teach them otherwise.

[mousquet]

Originally Posted by jmecklenborg

Trees aren't a new idea.

No one said it was new. We're just talking about the significance of trees in urban planning here. That's an important topic in cities whose urban fabrics are very dense.
When we discussed it on the French forum, we noted a couple of difficulties about growing more trees in town.

1. Developers often see greenery as a waste of room. They'd rather build more condos to increase their turnover and profits.

2. Some municipalities would be a little reluctant at the thought of more gardens in the public realm, because it means more expense to them. You need to pay for gardeners to maintain green spaces.

Everybody knows about the benefits of trees cause it's quite obvious indeed, especially in a time when heatwaves will be more and more frequent.
But then, you have to deal with particular interests that don't necessarily advocate greenery in their projects.

[ChrisLA]

Originally Posted by sopas ej

Reminds me of a meme I saw this morning:


Regarding Los Angeles and SoCal, people seem to think that there's no such things as aquifers and underground streams/rivers. Once tree roots hit a water table, you don't even really need to water it.

Here are few samples of native SoCal trees, from California Native Trees.

Arctostaphylos “Sentinel” showing off its winter flowers.


Sycamore.


Quercus agrifolia.

]

Thank you, I’m a native Angeleno and I say give me my shade and tree line streets.

Me thinks that if this bugs someone, don’t move here. As you stated there are a lot of trees here that do not require us to artificially water them. Eucalyptus trees can go for months without water, during the dry summer season.

There actually aren’t any natural cities, the trees we see on the boulevards are part of the design landscaping. It’s the same in the residential areas of most of the wetter regions of this country as well. So should we not plant them in those cities because they aren’t part of the natural landscape.

By the way I actually love the 2nd photo, the native plants are so much more interesting to see than some boring green grass. That’s the beauty of Southern California, it’s quite colorful.

[homebucket]

Originally Posted by ChrisLA

Thank you, I’m a native Angeleno and I say give me my shade and tree line streets.

Me thinks that if this bugs someone, don’t move here. As you stated there are a lot of trees here that do not require us to artificially water them. Eucalyptus trees can go for months without water, during the dry summer season.

Are eucalyptus native to Southern California? Up here in the Bay Area, they have a horrible reputation for being invasive trees from Australia. They also shed a ton of bark and are a huge fire hazard, being one of the main contributors to the Oakland firestorm of 1991.

[hauntedheadnc]

Originally Posted by jmecklenborg

Many US cities have woods and big trees all over the place, and not as part of some plan endorsed by Twitter or wherever this article came from. Trees aren't a new idea.

The article came from ZME Science which, according to an organization that would know, knows more about the issue than you do. So you can stop being petty and harumphing about the topic like an offended old spinster any time you like. Nobody said trees were a new idea. We know they aren't. No shit, Sherlock, as some would say, even.

What is new though, is to be able to work the quantified benefits of trees and greenspace into costs and projections, and to maximize their impacts in architecture and urban design. To, for example, be able to figure out exactly how many trees it would take, and what kind, and where they should be placed, to appreciably cool the Place de l'Opera in Paris.

And correct me if I'm wrong, things like that are what we're here on this forum to discuss.

Also, many poor Americans don't understand nutrition/hydration and refuse to drink water and/or electrolytes while working in the heat or while just sitting around. You can't teach them otherwise.

Well, you've convinced me. I, too, am now offended by the presence of trees in urban areas, and I'm even more offended that anyone would try to quantify their benefits in the built environment. How dare they? Have these so-called "scientists" no decency?

[Nouvellecosse]

Originally Posted by hauntedheadnc

Well, you've convinced me. I, too, am now offended by the presence of trees in urban areas, and I'm even more offended that anyone would try to quantify their benefits in the built environment. How dare they? Have these so-called "scientists" no decency?

I think he just means that people who fall within a broad income or class category are all the same and are incapable of comprehending basic health and nutrition concepts due to their inherent inferiority. Yay science!!

[JManc]

One thing I really miss about living out in California. Bougainvillea. Everywhere.

[ChrisLA]

Originally Posted by homebucket

Are eucalyptus native to Southern California? Up here in the Bay Area, they have a horrible reputation for being invasive trees from Australia. They also shed a ton of bark and are a huge fire hazard, being one of the main contributors to the Oakland firestorm of 1991.

You’re correct they are not native to Southern California. I haven’t heard of the fire danger, and most of the ones I see here are along the highways or in areas where there is a lot of agriculture. I was told they were a protection and sort of a wind breaker but I can’t say for sure if that is a fact.

When I resided in Fresno, the apartment complex I lived in kept the eucalyptus trees as part of the property landscape when they built the complex. I had a an awesome view of them from my unit, and I loved the scent that came from them, especially when the wind blew.

[badrunner]

Bougainvilleas, Jacarandas, Lily of the Nile are some of my favorite flowering plants in SoCal. But there is one that really gets the blood pumping that you don't often see or hear about. If you've spend any significant time here, your nose knows. Who can ever forget that intoxicating fragrance permeating the air on those cool summer nights?

Night Blooming Jasmine

https://en.wikipedia.org/wiki/Cestrum_nocturnum

[sopas ej]

I love night blooming jasmine. You can really smell it at night in late spring/early summer as you drive into South Pasadena and San Marino.

I've heard that some people get headaches from the smell.

[craigs]

Plant a tree, get $100 under new MWD program aimed at expanding SoCal’s tree canopy

Lila Seidman
Los Angeles Times
March 6, 2024

With many areas of Southern California starved for shade, the region’s largest water supplier has launched a rebate program offering residents and businesses up to $500 as an incentive to plant trees.

The Metropolitan Water District of Southern California on Tuesday announced the addition of the tree incentive to its long-standing turf-replacement program, which offers cash to property owners who rip out water-guzzling grass and replace it with drought-tolerant landscaping.

Starting this week, new applicants can seek a $100 rebate for each eligible tree planted — up to five trees total — as part of their turf-replacement project, according to a spokesperson for the district. Qualifying residents will also receive $3 for each square foot of grass lawn they replace with native plants, up from $2, due to a federal grant. The higher rate will last until the grant runs out, officials said.
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