The Double Tree of Grana

Joshua Foer is a guest blogger on Boing Boing. Joshua is a freelance science journalist and the co-founder of the Atlas Obscura: A Compendium of the World's Wonders, Curiosities, and Esoterica, with Dylan Thuras.

I'm awed and wowed by the huge number of incredible places that people have been adding to the Atlas Obscura over the last couple days. It's especially neat to see folks contributing the sorts of local curiosities that are not only not listed in conventional travel guides, but are barely mentioned anywhere else on the web. Like this odd tree in Grana, Italy, submitted by a user named Alpha:

A very unusual tree grows in the town of Grana, Italy--or rather, an unusual pair of trees. It consists of a fruit tree growing on top of a common willow tree, creating a kind of two-tiered, two-species hybrid duplex. While it's not uncommon for a small tree to grow on a larger one, it is rare to see two fully grown trees in such an unusual configuration. Nonetheless, the arrangement appears to be working well for both individuals, as the fruit tree on top bears lovely white flowers.

[#1 posted by Takuan, June 17, 2009 9:04 PM]

http://en.wikipedia.org/wiki/Nurse_log

[#2 posted by 3.14chan, June 17, 2009 9:21 PM]

I didn't knew that!
Thank you!

[#3 posted by DaveP, June 17, 2009 9:25 PM]

you'd get a real kick out of my folks' avocado ranch, where they have about 100 of these. piggybacking a useful tree on top of the hydraulics of a less useful tree is done lots of places.

[#4 posted by thequickbrownfox, June 17, 2009 9:26 PM]

Not exactly double trees but some species of palm, at the end of their lifespan, sprout a massive inflorescence that gives the appearance of another tree growing on top.

Tahina spectabilis http://news.bbc.co.uk/2/shared/spl/hi/pop_ups/08/africa_enl_1200540133/html/1.stm

Corypha elata http://edis.ifas.ufl.edu/LyraEDISServlet?command=getImageDetail&image_soid=FIGURE%2013&document_soid=EP263&document_version=48150

[#5 posted by mattofdoom, June 18, 2009 1:49 AM]

@ #4, TheQuickBrownFox

After spotting some trees in a Botanical Garden in West Africa that seamed to repeatedly, enthusiastically switch between being palmish and woody-truck-and-branchish I've been dieing to find out what I was looking at. Your trees are the closest I've seen.

Do you have any idea what I might have been looking at?

[#6 posted by Beanolini, June 18, 2009 2:16 AM]

the arrangement appears to be working well for both individuals, as the fruit tree on top bears lovely white flowers.

It appears to be working well for the tree on top; the willow underneath doesn't look especially happy.

[#7 posted by Anonymous, June 18, 2009 2:46 AM]

maybe the fruit tree is a "barone rampante" specie...

[#8 posted by thequickbrownfox, June 18, 2009 2:54 AM]

@ MattOfDoom

Well the palm trees I mentioned are Hapaxanthic, which means they seem to grow for a long time as ordinary palms and then suddenly sprout this inflorescence, and then die.

[#9 posted by mattofdoom, June 18, 2009 3:15 AM]

@ #7, TheQuickBrownFox

Thanks, 'Hapaxanthic' gives me a starting point for a bit of wikitrawling.

[#10 posted by dculberson, June 18, 2009 8:02 AM]

They have a lot of parasitic plants including trees in rain forests.. the competition for light is fierce so getting a start on top of another tree is a big boost to a plant's chances of survival.

When looking into it a bit I came across a cool looking plant - the strangle fig. Here's a neat pic or two:

http://www.flickr.com/photos/aacool/3600794227/

http://en.wikipedia.org/wiki/File:Strangler_fig_boulder_katandra.jpg