"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!

Tropical Agriculture: Vegeculture

For this blog, I wanted to do something a little different. The way that agriculture "works" in different countries around the world is very different from what we, as North Americans, are used to. When I first found out that you could grow more than one crop in a field at the same time I was baffled. I had grown up driving up and down the 401/402/403 corridor where you see nothing but endless fields of corn (or wheat or soybean or whatever it is that the farmer is growing in the rotation that year). Or, if the farm had been subdivided into smaller plots, each plot would still be its own crop. I've even driven repeatedly by a sod farm and was amazed that people actually farm grass (but I guess sod does have to come from somewhere, doesn't it?!).

In warmer climates in Central and South America, as well as almost all of Asia, some of Australia and almost all of Africa, agriculture is very different. Instead of relying on one crop for a field, a whole bunch of crops are all planted at the same time in a small area. The idea is that if one crop fails, you still have other sources of food to rely on. Very few of these crops would interfere with each other, and some might even act synergistically to increase yield. A very exciting prospect, especially as we are struggling to produce enough food for the world's ever growing population. So how does this work? It's not just a haphazard mess of plants in a dense thicket and you get what you get. There is still a significant amount of order in a tropical food plantation, and there's a lot of planning that needs to go into making sure that taller plants that will grow into trees or large shrubs won't be planted near plants that cannot tolerate shade. Plants with vast root systems should be planted near the bottoms of trees that are already established so they can't compete for resources (the tree would almost always win that battle!). This type of agriculture is sometimes referred to as "vegeculture" (monoculture planting in cooler climates is called "seed planting" agriculture), and since I was lucky enough to be able to visit a small farm in Dominican Republic I figured it was worth exploring a bit.

I present to you...vegeculture!

These first two are photos of what a typical farm plantation might look like. You can see that there's still a semblance of rows that are planted, but the rows also each have more than one plant species. There is no effort put into weeding or spraying against weed volunteers (a "volunteer" is either a plant seed from the previous year's crop that pops up during the current growing season, or an adventitious weed that grows much faster than the crop you're trying to grow). Weeds are typically short-lived plants, and if you plant creeping vines as has been done in the upper photo then this is less of a problem (or is very quickly eliminated as a problem). So what do we have here? How many crops can you actually see in the photo? Well, when I was on the farm I counted at least 8 different crops in a very small space but now (of course...I didn't write them all down) I can only see six. So let's look at each one of these using the top photo, zooming in on some that can be distinguished easily (at the very least, picked out with the help of coloured boxes...).

Red box: This plant is very, very hard to see but it's certainly worth a short discussion. Between rows, cassava (Manhiot esculenta) is planted. Cassava, sometimes called yuca (NOT yucca!) or tapioca, is planted. The crop harvested from this plant are the very deep-growing storage roots that are used in a manner similar to a potato. The downside of cassavas is that they contain cyanogenic alkaloids (aka cyanide) and must be prepared very carefully. Once prepared properly, they can be sliced and fried or mashed and are often consumed in a stew-like preparation as a side dish for chicken.

Blue box: These are pineapples (Ananas comosus)! Immature pineapple plants just look like spiky plants you don't want to come across in a dark alley, eventually growing into the plant that can be easily recognized as a pineapple plant from my last blog post (which you can read HERE).

Yellow box: This is a low, creeping vine that is often propped up (either on stakes or in a more natural form as a corn stalk or sunflower stalk) off the ground. These are sweet potatoes (which might be called yams but are NOT true yams; Ipomoea batatas), grown for their sweet, potato-like fleshy root. Sweet potatoes, unfortunately, aren't always sweet. There are definitely the sweet sweet potatoes that we are used to in North America and that Europeans are used to, but there is also another variety (some call it species) that is much less sweet-tasting. There are also very lightly coloured sweet potatoes (not the bright orange-yellow sweet potatoes we're used to) which may or may not be correlated with sweetness (up for debate).

Pink box: This very tall, grass-like crop is sugarcane. There are actually two different types of sugarcane present, one called black sugarcane (the one that's outlined in the box with the black-purple stem) and regular sugarcane (the tall grass in the purple box; both the species Saccharum officinarum). Black sugarcane, while loaded with sugar, is not used to extract sugar from. Instead, in the Dominican Republic, it is used to cook some of their traditional foods and is eaten whole when young. The regular sugar cane is what is grown for sugar extraction.

Purple box: Bananas, relatively short-lived as far as "trees" go, are often planted as a staple crop in tropical countries. Sometimes these banana trees are true bananas (Musa acuminata x balbisiana; read all about bananas HERE), while the rest will be plantains (the same species, but a different hybrid cross). They are much starchier than dessert bananas, and are much more versatile in cooking. The dessert bananas, part of the ABB subgroup, mean that they have two times the number of Musa balbisiana chromosomes in their genome than plantains, which are in the AAB subgroup (twice the Musa acuminata genes). It seems as if the back-cross, what gives that second either B or A genotype, is what determines the sweetness versus the starchiness of a banana.

Brown box: This is a coconut palm tree (Cocos nucifera which you can read all about HERE). Interestingly, there are more coconut trees in the Dominican Republic than there are people and all of them are owned by the government. If you want to buy coconuts they are delivered by the thousand (yes, that's right. The smallest number of coconuts you can buy at a time if you are a Dominican citizen is 1,000 coconuts) in a truck, and you're set for quite a while. Coconuts are one of the most versatile foods in tropical countries because they're not just used for food! If you carefully cut out the flesh you can use the leftover hull as a drinking vessel, the juice on the inside (the coconut water) can be used instead of saline solution in hospitals or cooked with, the flesh can be turned into coco butter or coconut oil for cooking (or eaten cooked or raw), and the hulls can be burned for fuel. The hulls also contain very strong fibres that can be woven into mats or cordage. You can see why they're so popular! The wood of the tree can also be used as either firewood or as a building material, depending on the age of the tree (the older the tree the less structurally sound it is, and the less likely it can be used, or would be used, to build a house).

This is just a small sampling of the number of species this one farm was growing; they also had breadfruit, mango, papaya, cotton, peppers, sage, basil, coriander/cilantro, thyme, allspice, coffee, cacao, tamarind, and annatto (to name a few...)! A pretty productive farm, and nowhere near the size of a multi-crop fruit and vegetable farm in Canada or the United States!

Unfortunately, more and more "traditional" cropping systems are popping up in Central and South America, due mostly to the influence of North American principles on traditional practices of South Americans. Sugarcane, banana and tobacco plantations are becoming more and more prominent, and are leading to serious problems with crop losses because of multi-chemical resistant pathogens that are attacking the fields. This is also leading to increased spraying, and since there aren't as strict regulations in these areas with chemicals that can and cannot be used on edible food this is being passed down to consumers in countries that import these crops. Many of these chemicals are highly carcinogenic, meaning they can cause cancer in very small quantities. Others are highly allergenic, and may explain at least part of the reason why some children are developing multiple food allergies. For example, there is a very high prevalence now of children being diagnosed as being allergic (or "intolerant") to gluten. Strangely enough, these same kids have no problem if they're eating homemade bread. It's just the bread in the bag from the mass-producer that causes them problems. Obviously this isn't a case of gluten intolerance; gluten is in all wheats, regardless of where it is acquired or how it is processed or who bakes the bread. The difference is in the number of chemicals on the wheat itself: if you bake your own bread you have the choice of where you obtain your wheat flour and if it's "organic" (however the farm or governing body defines that word) or not. A very interesting theory, and time will tell if there's any weight behind the idea!

The palm with the pony's tail

Species name: Beaucarnea recurvata

Common name: ponytail palm

Location: UWO Greenhouse

The ponytail palm is not a true palm, and its closest relative might surprise you. It is native to Mexico, but is used as an ornamental plant throughout much of the southern United States (it is cold-hardy to 6 degrees Celsius and is incredibly drought tolerant), South America, tropical southeast Asia, and Australia. This "tree", like true palms (one of which you can read all about HERE), is not actually a tree at all. It has no tissue called the vascular cambium, which is responsible for producing secondary xylem which is what we refer to colloquially as wood. If you don't produce true wood because you don't have secondary xylem, you can't be a tree! There are many monocots that masquerade themselves around town as being woody; bamboo, lucky bamboo (a completely different group of plants), palms, tree ferns and bananas all lack the ability to produce true wood (you can read all about bananas HERE). This doesn't mean that we can't use them as building material! All of these species produce a tissue type called sclerenchyma in great volumes which contributes to their stem stability (except banana; they produce collenchyma which is a tissue very similar to sclerenchyma. They also don't have a true above-ground stem!).

The ponytail palm, as mentioned, isn't a palm at all. It's actually a close relative of the asparagus family, and if I had of caught this plant while it was flowering it would have been much more obvious. The flowers produced by this species are almost identical to the flowers you would see if you let the asparagus in your garden go to seed. It's amazing the kinds of morphological variation you can get within a family!

The swollen base of the stem of this plant is designed for prolonged periods of drought. It almost acts as a water canteen, which can allow the plant to go for months without a significant source of water. If the plant went long enough, the base of the stem would start to shrink as the tissue and the water it contains starts to be reabsorbed by the plant. During the next major rainfall, the plant would reabsorb its water again and regrow the swollen stem base.

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?!