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| Quercus humboldtii in Jardín Botánico de Bogotá (click on images to enlarge) |
I spent a weekend in Bogotá in October 2017 and made it my mission to find Quercus humboldtii. I had had the species in my sights for a long time: it is the only oak native to South America, and so the closest non-cultivated oak to my residence in Montevideo, Uruguay (a mere 4,700 km as the crow flies—though it might take a relay of crows to make the trip!). Known in English as the Andean oak (it grows in the Andes, the South American section of the American Cordillera), it was named by Bonpland in honor of his travel companion on his travels through South America and Mexico, the renowned German botanist and explorer Alexander von Humboldt. I knew there were specimens in Bogotá's Botanical Garden, and understood that there were also trees of this species planted as street trees. I did not have to look far: straight in front of my hotel I found a line of oaks planted along the median strip of a wide avenue. And I was to come across several similar plantings in other parts of the city, including seedlings that had evidently been planted quite recently. According to the herbarium of the Jardín Botánico de Bogotá, the status of this species is Vulnerable (in the IUCN Red List it is listed as Least Concern, but that may be in process of revision), due to being under threat in the wild as a result of loss of habitat. However, it is alive and kicking in Bogotá, with 9,942 trees recorded in the city's inventory of trees[1].
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| Quercus humboldtii planted in median strips in major avenues |
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| Detail of leaves and acorns covered in pubescence that easily rubs off when touched |
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| Large specimen on median next to the Botanical Garden... |
...and by a railway track between two access ramps |
My visit to the Jardín Botánico was centered around an impressive specimen of Q. humboldtii (known locally as simply “roble”), as well as a section of the garden where an oak-dominated habitat has been replicated (“El Robledal”). Also of interest was a cousin, Trigonobalanus excelsa (syn. Colombobalanus excelsa), of which there are two specimens in the garden. Trigonobalanus is one of the smaller genera within Fagaceae, and includes three species (the other two are native to Asia). T. excelsa is endemic to Colombia. Scroll down for more photos (be sure to click on the images to view them enlarged in a new window).
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| Detail of new growth |
Catkins |
A recently planted seedling |
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| I found Quercus humboldtii acorns at different stages of development |
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| Detail of leaves on tree growing next to highway |
Bark is fissured and dark (perhaps affected by pollution) |
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| Entrance to Botanical Garden in Bogotá |
Sign next to old specimen of Andean oak (see photo at top) |
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| Sign at entrance to oak forest in Botanical Garden |
Oak forest (robledal) recreated in Botanical Garden |
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| Trigonobalanus excelsa |
Mottled bark of Trigonobalanus excelsa |
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| Detail of Trigonobalanus excelsa leaves |
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| Fruit on Trigonobalanus excelsa |
Empty seed cupules |
All photos © Roderick Cameron
