The last of the palms: Otto von Bismarck's tree

Species name: Bismarckia nobilis

Common name: Bismarck palm

Location: Dominican Republic

Well, we have finally come to the end of my images from Dominican Republic, and this is my last plant species to profile from my lovely vacation in February (I can't believe these pictures have lasted me until May! I need to go on vacation more often...). I figured since it's the last one, I should probably go out with a bang...

The Bismarck palm is native to, like almost all palm species, Madagascar and is declining in numbers there (like many, if not most, of their endemic plant species). The fertile land is being cleared and converted to agriculture, with a few select trees being saved to represent landmark "specimen trees" throughout the landscape. Bismarck palms can be incredibly long-lived, have enormous canopies if given enough space, and provide great shade and habitat for other species. By leaving even just a few Bismarck palms, Madagascar is potentially saving tens of species who use these trees as refuge. Unfortunately, agricultural crops are worth far more money to the economy of Madagascar, and these trees likely don't stand a chance of sticking around for long. It's a shame; a country that was once one of the most biodiverse locations in the world is now becoming a barren agricultural landscape. I know I've poo-poo'd on Madagascar in a few blog posts, but the more people know about their biodiversity crisis the more that can be done about it. World economies really need to start putting pressure on countries that house the most diversity to stop cutting down forests because the species themselves have some sort of economic value. It's a slippery slope once you put a price on diversity, but it's true what they say in the business and commerce world: Money talks. Fortunately for the worldwide population of Bismarck palms, they are planted in huge numbers around the world as ornamental species (in the tropics and sub-tropics; they can actually survive temperatures as low as -6 degrees Celsius for short amounts of time). There are two main varieties of this tree: the green kind that's pictured above, and a variety that is almost blue because of a very thick layer of wax that is deposited on the outside of all of the leaves (which you might guess would be much more tolerant of drought and cold snaps; you would be correct with that assumption).

Bismarck palms are some of the most easily recognizable palm trees in the entire world...once you know what you're looking for. They have characteristic fan-shaped fronds with a very thick petiole connecting the leaves to the trunk of the tree. These petioles, as you can see from the image with the pink arrow, are curved presumably to allow the fronds to sway from side to side but prevent the snapping of the fronds if shaken up and down (since we all remember from elementary school that an arch is much stronger than a straight line...right?). This also provides a really unique habitat for animals, other plant species, fungi, and even bacteria since all of the rain that the fronds catch is funnelled down the petiole towards the trunk of the tree. Because the bases of these petioles are so warm and moist, they usually rot right off the tree before the leaf has a chance of dying, especially in very warm, wet areas. The inflorescences produced are also quite characteristic, and look a bit like marine ropes emerging from the base of a leaf. These mature into flowers (some male flowers are pictured in the 8th image; you can tell because they are full of stamens and very little of anything else), which either produce pollen or ovules. These trees, like the pacaya palm (which you can read all about HERE), are dioecious meaning one plant either produces male or female flowers but never both. The trees with the female flowers end up producing the fruit, which starts off green when immature and ripens to be yellow or brown (you can see the green fruit in the bottom image). The fruit are not reported to be edible by humans, although I'm sure someone somewhere has tried them. These are the preferred fruit of some birds and other animal species, so these trees do play an integral role in the food webs of the ecosystems they're living in.

I keep mentioning that these trees are integral parts of their ecosystems, so I think it's about time to show you what I mean. In the two pictures below (the same image, the first one is unaltered and the second one has a bunch of boxes around interesting features) you can see symbiotic plants and animals all living in the same tree:

The green and yellow boxes show the fruit of the Bismarck tree: the green box shows the immature green fruit and the yellow box shows the more mature yellow and brown fruit. Inside the pink box are three different species of plants, the heart-shaped leaf vine, the oval-shaped weedy plant, and the roundish-shaped weedy plant. What these species of plants are I have no idea; they were about 15 meters in the air and I wasn't about to climb the tree to find out! There are also a whole lot of sticks at the top of the tree, which is weird (in the purple box). In fact, I'm guessing that's the way those three plant species managed to make it up into the top of that lone tree; there are no trailing stems or roots to suggest that they "climbed" up there. In the orange box we have a lone bird, who seems to just be hanging out on an old petiole of a leaf. But is he really?

Well, Mr. Bird there isn't actually just hanging out on a petiole by chance; he's protecting his nest. Yes, that massive thicket of twigs was more than likely made by that ridiculously tiny bird (you probably are aware of the species; we call them "that brown bird that makes all the noise at 5 am during the spring" and this common name probably reflects about 500 species of bird). In fact, we stood under the tree for a while and watched more than one of these little brown birds fly to and from the nest; there's likely a whole family of them living up there. In hindsight, it was probably pretty stupid standing under the tree staring up at them (not that I'm afraid of a tiny brown bird or anything): if you're really observant you'll see white patches all over the underside of the palm fronds. Those aren't patches of fungi. Those are patches of "bird paint."

Here's another example of plant species that exploit this tree. Again, I have no idea what species this is since they're just tiny seedlings, but these are growing from seeds that would have been blown down those arc-shaped petioles and landed at the base of the leaf where there is likely an accumulation of organic material that is damp and warm: perfect conditions for plants (amongst other things) to germinate. These plants likely won't last long being squished into a petiole like that, but depending on what species they are they might be able to complete their entire life cycle without ever leaving the protection of their host plant. If those are species that are perennials or require much more space to grow, they'll likely die before producing anything substantial.

And, like I promised in my first blog post about pictures of plants I took while in the Dominican Republic, lizards also call this tree home. These pictures represent what is likely two different species of anole lizard (Anolis spp.) that are in all likelihood native to Dominican. If you think about it, these trees are absolutely perfect habitat for lizards to hide from predators in the petiole hollows, build nests at the bases of petioles, and jump from leaf to leaf to catch bugs to eat. They were pretty curious as to what I was doing holding a camera so close to their home; I guess I did neglect to ask them permission to photograph their treehouse. Next time I'll make sure to bring "lizard waivers" with me!

I hope you've enjoyed the rather long series about "Plants in the Dominican Republic" over the last few months! 

"I've got a lovely bunch of..." revisited

Species name: Cocos nucifera

Common name: coconut palm

Location: Dominican Republic

If you think you've seen this before, you're partially correct. I have blogged about the coconut palm before, and you can read about it HERE. This was before I had really decided what I wanted my blog to become, and when I took the photograph that I used I certainly had no idea it would one day become a blog post. I figured it would be fitting while I was back in the Dominican Republic to take a new set of photos of a coconut palm and do this properly. So here it is!

The location where the coconut palm is native is currently a heated debate. There is pretty strong evidence that the tree originated around or near the Indian Ocean, since many of the uses of coconuts date back to ancient times in India. There's also more to it than that; there are also fossils from the Eocene period, 35 to 55 million years ago, in Indian rocks that depict species strikingly similar to coconut palms (these are also found in Australia). To complicate matters, coconut palms have also been used for centuries by various groups of people in South America, and there are fossils there, too, that depict coconut-like fruit in rocks that are even older than the Eocene period. So who wins? I'll let one of the experts decide that; I'd rather not have either India and Australia mad at me or all of South America :) Regardless, it's not native to the Caribbean and yet is one of the most important crops there.

Coconut palms require very unusual conditions for growth and germination of their seeds (coconuts are really seeds!). First, they have to be exposed to tremendous amounts of sea water. This helps rot away some of the hard fibrous outer husk to reveal the inner seed coat. This coat then needs to be cracked, either by the growing plant or through the natural abrasion of coconuts crashing in the waves against rocks, in order for the new plant to establish itself. The growing conditions are equally unusual: they require full sunlight, very hot temperatures, high humidity, sandy soil, and high salinity. None of these conditions on their own are very conducive to plant growth, and when you add them all together it's miraculous the plant can grow at all. When you consider the habitat in which the seeds are deposited, this should be a no-brainer that coconuts have evolved to tolerate and thrive in these conditions. They thrive on hot sandy beaches where the ocean is ready to take away the coconut fruit, transporting them along ocean currents to a new beach where they can crack open and establish themselves.

Aside from their obvious edible uses, one of the most exciting uses of coconuts is in the medical field. "Medical field?!" you say? Yes, the medical field. Coconut water is gaining popularity as a sport drink to restore electrolyte balance in the body. Does the average person need to drink it? No. Just like the average person has absolutely no use for the high-calorie and high-salt beverages bearing the names "Gatorade" and "Powerade." High-performance athletes like professional athletes or people on high-performance teams absolutely DO require some sort of electrolyte replacement. Nothing will replace your lost body water than water, but if all you're drinking is water while sweating buckets for 2-3 hours (in some cases 5 or 6 hours, depending on the sport) you're going to start feeling dizzy and get muscle spasms. This is your body trying to tell you that you're losing too much sodium and potassium (amongst other things) to be sustainable and it needs more. Enter: sport drinks. These are absolutely chock-full of salts and sugars (as well as some complex carbohydrates, but those are by far fewer in number than sugars) to replace what you're using and to give you a short burst of energy. "Normal" people who go to the gym for an hour a day definitely don't need sport drinks! So what does this have to do with coconut water? Well, it's been shown that coconut water has an almost perfect electrolyte balance in it that is in synch with what the body needs. Replacing your lost fluids, at least some of them, with coconut water is significantly more beneficial than a sugar-filled sport drink.

Now, you might be scratching your head and wondering how this was discovered in the first place and what sports drinks have to do with medicine. I always appreciate an inquisitive mind! Would you believe me if I told you that one of the first uses of coconut water in modern civilization was as a blood plasma replacement? Not only is coconut water completely sterile as long as the husk is intact, it also has that perfect body balance of nutrients and vitamins to be able to replace fluids lost through illness or massive trauma. During World War II it was mixed with blood units to dilute the blood (since it was so badly needed; they had to make what little blood they did have go further to treat more wounded soldiers) but still provide all of the benefits of blood plasma, then it was administered through IV to the wounded soldiers during surgeries. It can also be used as "IV fluids" either prior to surgery when the patient isn't allowed to eat food or drink liquid, or when the patient is having trouble keeping down food and water and requires replacement fluids. Coconuts aren't just good for making Bounty chocolate bars!

The last mysterious use of coconuts that many people know about but don't realize they do is as a commercial fibre source. These aren't fibres you can use to make clothing; coconut fibre clothing would feel similar to burlap if worn against the skin so I can't imagine that would be all that pleasant. Coir, what we call the fibre we get from coconut husks, is most often used as a matting material. Most of those brown scratchy "Welcome" mats you buy to put outside the door are made of coconut husks, as are a lot of the "fluffy" potting mixes that come with boxed bulbs like amaryllis bulbs. The "peat pellets" that you can buy at garden stores to start seeds indoors before transplanting outdoors are also often made at least partially of coir; they can be pressed into very small pellets and when put into warm water can absorb water and expand to be hundreds of times the original size of the pellet. It's actually a fascinating process to watch!

I've got a lovely bunch of...

Species name: Cocos nucifera

Common name: Coconut palm

Location: Dominican Republic

To me, this image represents one of the most iconic views of Caribbean countries: a vast beach of white sand dotted with palm trees and beach chairs. Sitting in my office marking tutorial assignments and re-marking midterms, there’s nothing I wouldn’t give to be on that beach right now! Anyone want to run away on vacation?!

Palm trees are actually not trees. They’re more closely related to the grass that grows in your front yard or the corn you eat for dinner than they are to any true tree. Their strength comes from cells that are specialized for support called sclerenchyma. The palm family of plants (Arecaceae) contains about 2600 species. Different species occupy almost every inch of land in tropical and subtropical areas, with different species being able to tolerate very dry or very wet conditions. Many species of palm are critically endangered due to land use change and deforestation, so preserving their environments is becoming increasingly important.

Most people don't realize that when you eat a coconut, you're eating the food stores that the mother plant has put away for her developing babies. That coconut you cracked open was actually a seed of the coconut plant, and given enough time would have developed into a new coconut palm. To do this is incredibly difficult, and would rarely (if ever) happen in a lab. Coconuts need to be exposed to very long periods of partial submersion in salt water (only partial, since coconuts actually float with their husk still intact). When a coconut falls onto the beach and gets swept away in a hurricane, it will be deposited on a new beach where it can grow and develop into a new coconut palm. A pretty neat method of dispersal, while not very efficient. The smaller the coconut fruit, the more heavily it relies on animal dispersal--small date palms rely on birds eating them in order for their seeds to germinate. Without the seeds having passed through the digestive system of a bird, they will not grow. How's that for a plant-animal partnership?!