Socotra Island

[Palm Dave]

Some of the most unusual plants in the world grow here:

http://freshpics.blogspot.com/2008/09/soco...e-place-on.html

[Morabeza]

It's an amazing place!

I created a flickr group for people to add their photos of Soqotra native flora in situ and ex situ.

Soqotra سقطرى Native Flora - http://www.flickr.com/groups/53701189@N00/

Also there is an excellent new book out, quite incredible, published by the RBGE "Ethnoflora of the Soqotra Archipelago". I highly recommend this book to all plant lovers!

The flora of this island group are endlessly fascinating and many species could have a bright horticultural future. Hopefully the collaborative work of the RBGE (Scotland) with the Yemeni government and local people will also contribute to help keep the flora from becoming highly disturbed and endangered as is what has happened in Hawai'i, and many other unique islands of the world.

[LJG]

Big fan of the plants there too. I think the most fascinating thing to me is how far away the island is from the Canary Islands, yet the Dracaena cinnabari is so very similar to a Dracaena draco. I know of convergent evolution and always wondered if this is the case or did a seed from a Draco (or visa versa) somehow float their? How could they look so similar for such a unique tree?

I also think what many people grow in SoCal as Dracaena draco, I think they really are Dracaena cinnabari.

[Morabeza]

Big fan of the plants there too. I think the most fascinating thing to me is how far away the island is from the Canary Islands, yet the Dracaena cinnabari is so very similar to a Dracaena draco. I know of convergent evolution and always wondered if this is the case or did a seed from a Draco (or visa versa) somehow float their? How could they look so similar for such a unique tree?

I also think what many people grow in SoCal as Dracaena draco, I think they really are Dracaena cinnabari.

Hi Len

I thought you might catch this thread as I know how much you like Dragon Trees!

Geological and paleobotanical study of N. Africa tells us that the Sahara was once rather green. Lacking phylogenetic study of the relataionship of D. cinnabari to other members of the genus, we can at least take into account that Soqotra is a continental fragment and that even today Dracaena serrulata is native to the south of Arabia ((Oman, Yemen (mainland) and Saudi Arabia)) & Dracaena ombet is native to both the Arabian peninsula as well as the African mainland (Djibouti, Eritrea, Ethiopia, Somalia, Sudan and Saudi Arabia) along side the Moroccan endemic Dracaena draco subsp. ajgal; it is plausible that D. cinnabari, D. serrulata, D. ombet and D. draco subsp. ajgal all derive from a common ancestor that once had a wide range across N. Africa when it was more hospitable. Of course I would not only love to see the phylogenetic relationships of the above mentioned species, but I would also love to see incorporated the relationships of Dracaena draco subsp. draco (Canary Islands, Cape Verde Islands, Madeira Is.) and Dracaena tamaranae (south-west Gran Canaria Is.) both of which are endemic to islands of volcanic origin not far off the western coast of Africa.

Certainly you have spent more of your life in California than I have, but I think your hypothesis that many Dracaena draco grown in California to actually be D. cinnabari is dubious. As seedlings their leaf morphology are quite distinct. Also the growth rate of Dracaena draco far surpasses the sluggish pace of D. cinnabari in CA. Thirdly, to my knowledge, seed of D. cinnabari wasn't introduced into CA until at least the 1950's(?). The oldest specimens I have seen in CA only have a metre or more of trunk. Then again perhaps you have seen much older ones than I have had the privilege of seeing! And fourth, adult D. draco subsp. draco have much wider, more glaucous and more lax leaves than adult D. cinnabari leaves which remain a dark forest green, stiff and narrow. As far as branching structure, I can see how similar they look, especially in the very old specimens.

Regarding convergent evolution and the location of the true centre of Dragon Tree diversity, is still a mystery to me, though perhaps someone has published something on this specific topic somewhere. There are the dracaenas of the south-east Asia, sub-Saharan Africa, the island of Cuba, and those of the Indian Ocean Isles and Hawai'i to consider as well!

[LJG]

D. serrulata and D. ombet (still looking for by the way ) are easy to tell apart. I still think it is Dracos going around often as D. cinnabari here.

Here are good examples of different looking SoCal plants. I can't see the ridge on the back of the leaf found in small Cinnabari.

http://davesgarden.com/guides/pf/go/81311/

 

These are found in Botanical gardens too.

 

Now look at Dracos:

http://davesgarden.com/guides/pf/showimage/13386/

 

I have attached three pictures of my Dracos. You can see similarities in leaves. Whatever the plants are in SoCal like I have are (as you point out, most likely Dracos, and I agree), there certainly seems to be two different forms. Look at mine. Longer leaves and are not real stiff. Yet as anyone can attest that has been to Quail, the Dracos there have shorter and stiffer leaves which are never dropping below horizontal. The trees do not look at full either. Here is Quail example. Some of the others are even more stiff with shorter leaves.

 

http://farm4.static.flickr.com/3190/257161...cee33ec.jpg?v=0

 

Now maybe this is related to the subspecies you pointed out. One is D. draco subsp. draco and the other is D. draco subsp. ajgal. But the thing that surprises me is why no one points these things out around here. Perhaps it is just cultural? Plants given good soil, fertilizer and an abundance of water look that much more different? Perhaps.

 

Here is one of mine. 9 branches from first flower.

 

 

Here are the leaves.

 

 

This is my largest and it was violently ripped out of the ground and moved to my house 5 years ago. I actually saved its life. This tree was planted in the 50s at an old house here in Vista. The owner babied all his plants and had an amazing garden. He died. Some druggies bought the place and the bank foreclosed a few years later. He was fire-selling the old oners plants. Anyway, you can see the leaves are different but it is the same height as the Quail sample. Much skinnier due to faster growth and being babied for 50 years I woudl venture.

 

[Morabeza]

Hi Len,

Thanks for the links to help illustrate what you mean in regards to the D. cinnabari seen in SoCA. There is a characteristic of juvenile D. cinnabari leaves that is lost as they age which D. draco subsp. draco never displays. Both this picture ( http://davesgarden.com/guides/pf/showimage/119780/ ) and the picture of mine when it was a baby ( http://www.flickr.com/photos/morabeza79/384274983/sizes/o/ ) barely show this detail, and since mine has grown out of that stage I cannot try to recapture the detail in a more effective way. If you look closely at the oldest leaves in both pictures it can be seen, albeit blurry, if you are looking for it. I'm referring to how the youngest leaves on D. cinnabari have distinctive mid-ridge that I would almost call a v-keel. More mature leaves of course begin to emerge completely flat, as is seen in the other three (quite old for CA) specimens featured on the Dave's Garden entry. Another illustration of this on a Hawaiian one with over 3m of trunk at Koko Crater BG, O'ahu is here: http://www.flickr.com/photos/morabeza79/409835116/sizes/l/ .

Koko Crater BG has both old established D. cinnabari and D. ombet which probably have the first shot at blooming out of all in cultivation (at least in the US), but they haven't yet. Huntington BG in San Marino is the one that produced all the D. serrulata seedlings that were distributed through the International Cacti and Succulent Society. Koko Crater's D. serrulata is still young and is from that batch, however I don't see why there wouldn't be a good chance that the Huntington's tree won't produce more seedlings for distribution in the relative future.

Congratulations on your two beautiful Dragon Trees. They look wonderful!

As for the variation within what is sold and grown as D. draco subsp. draco in CA, I can imagine that there is a degree of variation in morphology within the species or perhaps the very tight and strict ones are actually the recently described D. tamaranae or perhaps there has been hybridisation as well between the two species as they are both native to the Canary Islands, D. tamaranae endemic only to Gran Canaria Island (not to be confused with D. draco subsp. ajgal endemic only to Morocco). There may be many naturally varying forms of D. draco subsp. draco in CA horticulture, as well as D. tamaranae and introgression between the two, all being sold and tagged quite innocently as simply D. draco, for the naming of D. draco subsp. ajgal and D. tamaranae wasn't formalised until relatively recently. If there were time and money in it, sorting out the taxonomy using molecular data of 'Dracaena dracos' in CA might yield some surprising results.

[LJG]

I got one of the D. serrulata seedlings from Huntington. It would be sweet if the D. ombet tree did set seed. I would love to get some.

Thanks for sharing your knowledge here. It has been filed in the long term memory banks.

[Morabeza]

I got one of the D. serrulata seedlings from Huntington. It would be sweet if the D. ombet tree did set seed. I would love to get some.

Thanks for sharing your knowledge here. It has been filed in the long term memory banks.

Oh I am glad to hear that you did get a Dracaena serrulata. I had one from the same batch but donated it to Waimea Valley BG by February 2009 because it couldn't take the high rainfall after I moved 6 miles from (near Waikīkī) Kaimukī (20" annual precipitation average) to the back of Mānoa Valley with average 120" annual precipitation average. Hawai'i has some of the sharpest rainfall gradients over the shortest distances in the whole world!

It was potted in a very sharp draining mix that was filled with roots, and set atop warm asphalt. However the architecture if the D. serrulata leaves is very efficient, it seems they are designed to catch and funnel as much water as possible to the centre of each branch. Water will even sit there in the crown almost mimicking a bromeliad. By after only 6 months in Mānoa (probably 60" of rain) it began to develop some kind of crown rot. I treated it with systemic fungicide and brought it under cover from the rain. Here's what it looked like a month or two before it developed problems: http://www.flickr.com/photos/morabeza79/2954524334 in a 15 gallon pot. Since my future garden plan is to grow in a high rainfall area I decided to let go of my D. serrulata for good.

I almost donated my D. cinnabari too, for fear that it would begin to suffer like D. serrulata did, but instead of rot it showed its displeasure by heavy yellow spotting on the oldest leaves. Just a thought, but perhaps D. cinnabari has evolved to handle more precipitation over a longer period of each year than D. serrulata, which taking into account the climate it comes from, probably gets water on a less regular basis and must capture all it can when it is available. D. cinnabari is from a much higher elevation and I understand that a significant amount of the water they get is from condensed fog/clouds that pass through the high elevations on the island.

Glad we both love Dragon Trees

[Charles Wychgel]

Nice photos Jacob and Len and thanks for the info as well, I do love Dracaena draco

I have attached some pix of D.serrulata and D.cinnabari as seedlings, they look definitely different especially colourwise.

Unfortunately the D.serrulata rotted after planting out just like yours Jacob.

Also a pic of Dracaena serrulata growing since 40 some years in the garden of John Lavranos, he offered it to me (I live not far from him) but I am scared to take this precious one out and consequently killing it, do they transfer well?

I donated one of the cinnabari to the Palmetum in Tenerife, Carlo will take good care of it.

I have been thinking for a few years now to jump on the Marrakesj Express and look for Dracaena agjal and bring back some seed.

[Brian Bruning]

I'm interested in obtaining seeds or seedlings of any arborescent desert Dracaenas except D. serrulata which I already have. Please contact me at BBruning@hotmail.com.

[Brian Bruning]

As far as plant speciation one must look first to geology. Before the Mediterranean there was the Tethy's Sea. Africa was further south and Arabia was as yet attached to Africa. The Tethy's Sea connected the Atlantic to the Indian Ocean. Pinus canariensis and P. roxburgii of India are closely related. The genus Cedrus ranges from the Himalayan front, then again in Lebanon, Turkey and Cyprus and then again in the Magreb (Morocco and Algeria), Various species of Pistacia and Juniperous as well are here and there. The arborescent species of Dracaena are in the Canaries, Morocco and then again in the deserts of east Arica, Arabia and the island of Socotra. Then the Tethys Sea closed up and the Istmus of Panama formed and changed the flow of ocean currents and that dried out north Africa and the Middle East giving rise to mediterranean and desert climates. North Africa was last green about 5000 years ago during a pluvial period. There are ancient stone carvings there of alagators, hippos, giraffes and animals that now only live in the Sahel or south of it. All the species of Macronesia and those in proctected valleys and mountains are relicts of wetter times.

[Justin]

It's an amazing place!

I created a flickr group for people to add their photos of Soqotra native flora in situ and ex situ.

Soqotra سقطرى Native Flora - http://www.flickr.com/groups/53701189@N00/

Also there is an excellent new book out, quite incredible, published by the RBGE "Ethnoflora of the Soqotra Archipelago". I highly recommend this book to all plant lovers!

The flora of this island group are endlessly fascinating and many species could have a bright horticultural future. Hopefully the collaborative work of the RBGE (Scotland) with the Yemeni government and local people will also contribute to help keep the flora from becoming highly disturbed and endangered as is what has happened in Hawai'i, and many other unique islands of the world.

Really awesome - thanks for sharing. A lot of the plants look somewhat similar to the plants from the "Spiny Desert" in southern Madagascar.