San Diego Magazine went looking for the oldest tree in the city in 2020 and came back with this cypress, then about 128 years old.
Ancient Trees in Balboa Park
Balboa Park's oldest tree is a Guadalupe Island cypress, planted around 1892 under Kate Sessions's lease of park land, the one that obliged her to plant a hundred trees a year here.
It grows wild in exactly one place on Earth, a small island off Baja California where feral goats have long been the main threat to it, which makes a large mainland specimen unusual on its own. Nobody has published its height or girth. The rest of the park's mapped trees are younger and stranger. A Moreton Bay fig outside the Natural History Museum, planted as a five-gallon sapling for the 1915 exposition's garden show, has grown twelve metres round; a second, younger fig over Palm Canyon pours buttress roots down the slope like a flying support. A kauri from New Zealand stands by the Mingei Museum with no age on record. And on the grounds of Marston House, an Australian tea tree grows sideways rather than up, its low trunks rooting again wherever they touch the ground, likely planted by Sessions herself around 1906. All five are free to walk up to; only the museums beside them charge for what is inside.
All 5 stand in San Diego, which maps 6 remarkable trees in total.
This tree grows sideways.

Photo: BrokenSphere (CC BY-SA 3.0)
This fig went into the ground as a five-gallon sapling.
The roots of this fig do not stay underground.
There is a New Zealand kauri on the Plaza de Panama and almost nothing about it is written down.
Opening times and visitor information: Balboa Park.
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