I live near one of the rows of trees on that map, and I must say they are very pretty right now.
But one of Sydney's most famous jacarandas is missing from the map:
That's because it died. It was replaced with an identical clone, however it is still quite small.
I was expecting that most of the "unique" trees would be in parks, e.g. the Botanic Gardens, but then looking at the distribution graph, wow, I can see so much diversity in the street trees "long tail"; almost as much as park trees.
Would be cool to see the rest of Greater Sydney as well!
A huge amount of credit goes to the City of Sydney for maintaining an up-to-date dataset. The only other council which has publicly available tree data (as far as I can tell) is the City of Ryde, but it's from 2013, so not as recent.
We have a lot of them in Gauteng, South Africa; even though they're classified as an invader species. They can only be in urban areas and aren't allowed to spread. They look nice but smell like pee.
Here in South Africa we have lots of them too, especially in Pretoria which is informally known as "Jakarandastad". Looks beautiful around this time of year - blooming is usually Sep to mid Nov.
Example from a residential area:
I was about to respond in this thread about how personally attacked I felt - other cities are not allowed to brag about their abundant numbers of Jacaranda. But then I saw TFA says that Sydney /only/ has something like 1500 trees, which feels to me like not a lot.
There are a _lot_ of Jacarandas in Pretoria. Especially the older parts of the city. The trees enjoy protection from the municipality, and you are not allowed to remove them. For past roadworks projects they literally removed these very large and old trees, and planted them elsewhere. Like your picture, the city is truly a sight to behold in November.
I do love Jacarandas in Pretoria - but I have also read that they are not an endemic tree species and probably _should_ be eradicated. I'm not sure of the exact details, and I have to be honest I would be sad if we had to remove Jacarandas from Pretoria as it will change the character of the city a lot.
Googling tells me that Pretoria has about 70k Jacaranda trees, JHB might have even more (albeit that its much larger).
Related: Jacarandas in Johannesburg - https://morukuru.com/news/jacarandas-a-passion-for-purple/
"it is estimated that here are now more than 70 000 trees in Pretoria which is affectionately known as Jacaranda City. Johannesburg is believed to be the largest cultivated urban forest in the world with over 10 million trees and the Jacaranda’s contribute substantially to this number, as thousands were planted as street trees, in parks and gardens. Although difficult to confirm, some experts say Johannesburg has even more of these glorious purple trees than Pretoria."
Also many in Lisbon.
From the article :
They were brought by Felix Avelar Brotero, the father of Botany in Portugal, at the Ajuda Botanical Garden from 1811 to 1826. He offered seeds to whoever wanted to cultivate them in the city. They precede the return of the Portuguese Court from Brazil, at a time when blue spectrum pigments were very valuable. For the royalty this plant, due to its exoticism, had a non-commercial value: it was a way to demonstrate the royal power.
Aren't these considered invasive plants in Australia 
Sure are, same with camphor laurels, yet they're everywhere as well
Sadly, they aren't considered noxious enough to mandate their removal.
Having pretty blossoms seems to help avoid the classification.
They are so ubiquitous here I've had conversations with multiple people who think they are native. Apparently, seedlings were given to new parents from a maternity hospital in southern Sydney back in the day which helped their spread.
Sadly, their reputation seems to overshadow the native Illawarra Flame Tree (https://en.wikipedia.org/wiki/Brachychiton_acerifolius) which itself is showing off vibrantly right now. I'm lucky enough to have a few in my street.
Jacarandas were brought from South America. Reputedly the first Jacaranda tree grown in Australia is/was in the Brisbane City Botanic Gardens.
Off topic, but that website was quite unusual.
Judging by the title, I was expecting an article about perennial plants with elongated stems or trunks that usually support branches and leaves. Instead, I was met with a series of code blocks, briefly making me wonder if the piece was discussing a novel data structure based on traditional trees. After a few moments, the code blocks were either substituted or supplemented with the actual page content, reminiscent of Jupyter Notebooks. After about 10 seconds, it became unclear whether all the content had fully loaded.
Not the most user-friendly experience, in my opinion.
Agree, a bit jarring, and I don't think it ever quite answers the question either. I saw the title and decided it was a "how many gas stations are there in Chicago?" type lateral thinking question. I must admit without a lot of thought I blurted out an internalised "maybe 1 for every 10 people" (trees not gas stations) and so "500,000". I am wrong by several orders of magnitude. Whoops.
observable.hq is js notebook site. This is literally a notebook. Sharing notebooks containing this kind of analysis/visualisation is very common
I live in Sydney and we have a bunch of these on the street. There’s also one in my next door neighbours small back yard growing over my house.
I think I might be in the minority but I really don’t like them. The tiny leaves fall all the time and make a mess, and the purple flowers smell really bad and also make a mess.
Not only do they make a mess but they block my gutters and the roots have destroyed a lot of sewer pipes. I’d much rather see some native Australian trees planted such as paper barks or flame trees. I really don’t get the love affair with them.
They're not a great street tree because of the reasons you outline. But they do look spectacular for a short while in the year.
I wish someone would genetically engineer jacarandas so their blooms would last at least three times longer as by the time one realizes they're in bloom they're already making the ground mauve. The show is almost over before it starts.
Incidentally, that grouped listing of jacarandas in Sydney doesn't give a realistic picture of the total number of jacarandas. There are thousands of individual trees that transform the streets and you'd never know it from those figures.
I was surprised when I first saw a Jacarandá in Auckland, New Zealand. I was not aware that there were so many Jacarandás so far away from South America, nor that the name was the same in other languages. https://en.wikipedia.org/wiki/Jacaranda:
>The name is of South American (more specifically Tupi-Guarani) origin, meaning fragrant.
There are other Tupi-Guarani words that made it to other languages, like Açaí, Piranha, Capybara, ...
Sydney has less than Brisbane
Love to admire the purple flowers of jacaranda trees (there are certain spots in Southern California where they are everywhere) but when they fall on the ground it creates a nasty mess.
We had a massive beautiful one overhanging our pool in Australia, and not only did the flowers clog the filter, they wreaked havoc on the chemicals.
Every year Dad threatened to cut it down, and every year Mum threatened to divorce him if he did. They stayed married.
The tree stands to this day, happily filling the pool with a blanket of flowers
Reminds me of that old text adventure game Jacaranda Jim on MSDOS.
You don’t one near your residence. They drop slippery leaves everywhere.
Here in Buenos Aires we love them :)
How big does it need to be to make it onto the database? I think that adding it as soon as it's planted would be best, so you could track growth etc.
The city of sydney (local government area) is a very small part of the overall city - this dataset is just that area which is also the most densely built part (26 square km vs 12,300 square km)
Heresy! ONS is die Jakarandastad. (PTA)
What exactly is "noxious" about jacarandas? Most of us people admiring them are also invasive species.
As someone whos home is directly underneath two of them: their flowers somehow get through 2mm gutter guard mesh, and rot (which is annoying as heck and slippery if you're not paying attention).
They're pretty, for sure, but they're not without their detractors
I had a quick look and it seems that the Brisbane claim is contentious (like these things often are), according to Australian Geographic:
Brisbane claims the earliest jacaranda tree in Australia, planted in 1864, but the Sydney Botanic Garden jacaranda is dated at “around” 1850, and jacarandas were listed for sale in Sydney in 1861.
Either way they've been here quite a while, and longer than many family lines that consider themselves Australian. The midwife story I mentioned is also contentious because there are a few myths going around about North Sydney in particular, but I think the one from Sutherland had some facts backing it up, including a man who remembered gathering them as a child.
Good point! I was playing around with a "fun" title and really just wanted to map out all the Jacaranda trees in my area.
I've now updated the notebook and made sure the tree count is clearly mentioned.
Haha cute story...they stayed married..
My parents had the same problem. They divorced, sold the house, and the tree was subsequently cut down. I suspect they may have had other problems too.
Another tree used as a street tree here is white cedar (native) and it would have the same problem with rotting flowers, plus far more annoying fruit/berries that cause slips and try to start rogue trees all over the place.
Incidentally, what are considered ideal street trees? I know plane trees are out of favour (lots of leaf litter, annoying flower ball thingies). Crepe myrtles aren't tall enough for roadside plantings.
Yeah there's also the Leopard Tree which has the same problems around leaves too (we have one of those above our house as well!). I honestly don't know what would be better, I don't know enough about trees!