This plant has a few dirty little secrets

Species name: Gossypium spp.

Common name: cotton

Location: teaching lab at Western (first 6 images) and Samana, Dominican Republic (last 2 images)

Cotton is probably one of the most well-known plant products and the single most important plant fibre around the world, yet few people would recognize cotton growing in plant form, let alone if none of the "bolls" (more on that later) were present. Cotton plants are actually becoming more and more popular as ornamental species around the world because of their beautiful flowers which come in a huge variety of colours and sizes (partially dependent on species, but also on cultivar). Most back-yard gardeners would be lucky to end up with actual cotton seeds covered in fibres growing on their plant; cotton crops are the single most susceptible agricultural or horticultural crop to diseases and pests of all kinds: viruses, bacteria, fungi, insects, and even competition by other plants. As I'm sure you can assume now, the crop that requires the most "-icides" in the world is cotton: herbicides, fungicides, insecticides, and fertilizers. This makes cotton growing very, very detrimental to the environment, and there are some interesting side-effects to this type of spraying that I'll talk about later in this blog.

There are four main species of cotton grown around the world, and each one is selected for different reasons. Believe it or not, all four of the commercially cultivated cotton species are now at risk of becoming endangered in the wild because of over-harvesting. For a crop we grow so much of, that's almost hard to believe! Gossypium hirsutum, otherwise known as upland cotton or Mexican cotton, is native to Central and South America and represents 95% of cotton cultivation in the United States (about 80-90% of cotton cultivation worldwide). Gossypium barbadense, also known as extra-long staple cotton, is native to tropical South America and is highly sought-after for creating fine cotton garments and cotton cloth (Egyptian cotton and Sea Island cotton are almost always derived from this species). Unfortunately, it is incredibly difficult to grow because it requires high amounts of humidity in the air, high amounts of rainfall, and full sun to grow properly. This combination is rare in cotton-producing countries; where there is a high amount of rainfall the temperature isn't optimal, and where the temperature is optimal it is very dry. These factors contribute to why this species only accounts for about 8% of worldwide cotton production. Gossypium arboreum, tree cotton, is native to India, Pakistan, and surrounding areas of the Old World. This species was previously used to make fine textiles for traditional garments, but because of its difficulty in harvesting the cotton fibres (there's a reason why it's called tree cotton!) is now only accounts for less than 2% of the world's cotton production. It is still grown in cultivation in some areas in India for its traditional purposes. The last species used as an agricultural crop is Gossypium herbaceum, Levant cotton, is native to Africa and the Arabian Peninsula. While only accounting for less than 2% of the world's cotton production, it was the first cotton species to be represented in art form. It was first noticed by European traveler Sir John Mandeville, who described the growth of the plant as producing a melon-like fruit that when planted grew sheep. I couldn't make this up if I tried. He also drew exactly that: a melon in the ground with roots coming off of it, and the plant above it with a giant sheep growing on top. Granted, this was the 14th century and they didn't know much about basic biology back then, but still. Sheep don't grow on cotton trees! It wasn't until the 1800s that this story was officially deemed a fable; up until then there were actually Europeans that traveled to Arabia and sub-Saharan Africa in search of sheep growing on trees. A bit ridiculous when you look back!

Cotton fibres and the cotton seeds are produced in structures that are commonly termed the "cotton boll." These bolls contain anywhere from four to seven seeds, depending on the species. Each seed is covered in a dense layer of very short hairs called cotton lint, and then that is covered in a thick layer (or thin layer, depending on the species) of very long hairs called cotton linters. When we harvest the cotton from the plant, there is a machine that all of the cotton bolls are fed into that has razor blades that rotate very quickly, literally "shaving" the cotton seed of its fibres. The fibres are shaken, which eventually separates the lint from the linters and the linters are spun into long threads that can be used to make fabric. The longer the linters the stronger and smoother the thread. So what happens to all the rest of the "stuff"? Well, there's definitely a dirty side of cotton production, and that is the sheer amount of chemicals applied to most cotton fields. When the seeds and the plant flesh enclosing the cotton seeds are tested for toxic chemical levels, they are found to be containing dangerous chemicals at levels that are even too high to feed to pigs. This is a shame, because cotton seeds are actually incredibly nutritious, and being able to feed cotton by-products to animals would be a great use of these plant wastes! Today, most of it is either composted or burned. G. hirsutum is one of the species of cotton used most often to produce cottonseed oil, which is often produced from organic or nearly-organic cotton. This type of cotton cultivation results in a severely reduced yield of cotton fibres due to the cotton boll weevil, which uses the flesh around young cotton seeds as its primary food source. This doesn't harm the development of the seed (much), but does severely reduce the amount of protective covering the seed can produce (aka the seed hairs or the cotton fibres).

Aside from the fibre use and the new-found ornamental use that cotton plants have, they have also been used for centuries as a medicinal species. In both South America and in Africa, the leaves of the plant are pounded and ground into a paste and applied to the skin to treat hypertension and joint pain. The ground leaves can also be consumed to treat delayed or irregular menstruation. There is, actually, a high likelihood that this second use would be incredibly effective. Most of the time, especially before the advent of contraceptives, a delayed or irregular menstrual cycle is the result of pregnancy. One of the chemicals contained in cotton leaves (as well as raw cotton seeds and the tissues surrounding the cotton seeds) is called gossypol and it is a highly toxic chemical to all animals with only one stomach (like humans and pigs; cows are ruminants and so are, for some reason, immune to this chemical). The way that this plant is most toxic is as an abortifacient, or an abortion-inducing chemical.

Cotton production does have a dirty little secret in American history, and that is the use of African slaves. People were shipped over to the United States to spend all daylight hours picking cotton in the fields with little to no rest, and were paid meagre wages (if at all). The only reason why the United States is a major cotton producer today is because of their slave use: the more slaves you have, the more cotton you can produce. In fact, cotton production was the single most important driving factor of the importing of African people to the United States. Granted, cotton is no longer cultivated that way today (thank goodness!) and instead is part of a mechanized process. I often wonder what types of crops would be grown in the southern United States if the slave trade had never existed. Would they be as important in the cotton industry? What about peanuts? Or soybeans? All of these crops required a large amount of human input to grow, and so the only reason why they were ever grown is because of the opportunity to use slave labor. Interesting to think how such events in human history (and not just in the United States, but anywhere in the world where people are brought in to perform manual labor and especially farming) can drastically change the product exports from a country!

Cotton is also an important fibre crop in the paper-making industry. Paper doesn't require wood pulp in order to stick together; it can be made perfectly well from an old pair of jeans blended into a very fine pulp! Cotton fibre paper, sometimes referred to as "rag bond" (but not true rag bond as that's made out of linen or flax fibres), is also called archival-quality paper as it strongly resists decay. For every percentage point of cotton fibres in the pulp that goes into making the paper, an extra 1-5 years is added onto the life of the paper. The paper used for printing theses (which my monstrosity of a PhD thesis will be printed on and permanently bound one day) is 95% cotton fibres, so that adds an extra 95-475 years of life to my thesis. I'll have to provide explicit details in my will that once I die someone I know will go back and visit my thesis every few years between 95 and 475 years after I have it printed to see how long it takes before the pages fall apart. A morbid experiment, but could be a fun one!

The "Vegetable Lamb of Tartary," or the Scythian Lamb, as depicted by Sir John Mandeville (left) and Henry Lee (right) (images both from Wikipedia).

Sisal here, sisal there, everywhere a sisal sisal...

Species name: Agave sisilana

Common name: agave, sisal

Location: teaching lab at Western

So once again we have a plant in a pot (the next few blogs will all be plants in pots) from my favourite course ever. This plant is from the same lab exercise as the previous one, flax (which you can read all about HERE). The point of this lab was to introduce students to five major fibres and where the come from, as well as providing them with visual representations of what the plants actually look like since most are pretty foreign concepts to the average undergrad student. The five plants we feature are hemp (not as a plant, but we have a huge display about hemp cultivation and harvesting, as well as products commonly made, and some uncommonly made, from hemp), flax/linen, banana/musa, sisal/agave, and cotton. We also feature products made from each of these plants so the students actually get to touch the fibres to see what they feel like, and why one might be used for one thing over another (for example, it would be extremely unlikely for you to want to wear a pair of jeans made out of sisal, but some made out of hemp would be lovely).

Sisal, also commonly called "agave" after it's Latin name, is native to the Yucatan area in Mexico where it is still commonly cultivated (and found in the wild) today. There are many, many other countries that cultivate this plant for its fibres, not the least of which being my favourite country to visit in the whole wide world: Cuba. The story of how they started farming sisal is actually a funny one! Back in the "good old days" (the 1600s and 1700s, not the 1980s), world exploration was quite the hot topic everywhere in the world. Cuban people, whether it be immigrants to Cuba who have now called it home for decades or native Cubans who have lived there for centuries, were big into exploration after Christopher Columbus piqued their interest (he made landfall in Trinidad in Cuba, where he was attracted by all of the same plants he found in the Dominican Republic). They set sail for the west, hoping to come across something exciting and they did: Mexico. What they observed there was fascinating to them; people turning plants into beverages, and then singing and dancing after consuming those beverages. I don't know about you, but it sounds like a fun time to me! Cubans agreed, and offered to buy some of these plants off of their hands; Mexico refused. So what's a Cuban to do when you want to make the "happy drink" but they won't give you the plant to make it? Why you steal it, that's what you do. Minor detail: the plant in question was the plant called Agave tequilana, or perhaps even Agave americana, not Agave sisilana. Since pretty much all green spiky plants look the same after an over-indulgence of tequila, you can probably understand how they got the two mixed up. Once they brought the plants back to Cuba, grew them, and tried fermenting them into alcohol they were likely sorely disappointed since the resulting beverage would taste nothing like Mexican tequila (it's much more bitter, and would be a much darker brown). They quickly rectified their mistake by becoming one of the world's most important producers of sisal fibres around the world, used to make marine ropes and twine. At least it wasn't all for nothing!

Sisal has recently come back into fashion as an alternative plant to grow in an area, especially in tropical countries, when you're letting a field plot go to rehabilitate the soil as it out-competes weeds and animals avoid eating it because of its physical defenses. It will just happily grow, producing long strands of fibres in the leaves without any kind of human intervention. Even harvesting the plant for fibre is non-destructive; you simply cut the leaves from the stem and leave the stem to grow more leaves. Most commercial sisal varieties are sterile, meaning they will never produce the flower stalk that is so characteristic of other members of the genus Agave (which you can read all about HERE or a closely related plant in a different genus HERE). Should those flowers have been produced, the flower stalk could also be used as a source of fibre. Like with the tequila agave, once the flower stalk is produced and the flowers are pollinated, the entire plant dies so there is incentive for sterile varieties to be grown to prolong the life of the plant.

Aside from rope, there are many uses for sisal and even more are being discovered now that varieties of sisal can be produced in the lab that make longer, softer fibres. Sisal is now commonly used to make paper, dartboards, scouring cloths and sponges, filters, carpets, and even some texturized wall coverings (paints and wallpapers). Sounds like a great plant! The one major downside in using this plant as a fibre source is the amount of waste: only about 4% of the total mass of the plant are useable fibres. The rest is all waste that is composted (rarely) or burned (more likely). The odd time the burning of sisal waste will turn into a dirty fuel, but more often than not it's just set on fire in the field and the ashes are spread around after the pile has been burned off. There are now efforts into looking at how microbial decay by bacteria can be used to turn sisal wastes into biogas, or methane.

While not officially a state "tree" (not actually a tree, despite the ability to produce a stem that looks quite woody, as it is a monocot), it appears on the coat of arms of the state of Yucatan in Mexico, and Barquisimeto in Venezuela.

A plant you eat and a plant you wear

Species name: Linum usitatissimum

Common name: linen, flax

Location: teaching lab at Western

One of the courses that I've been involved with as a TA (and sometimes a guest lecturer if I'm lucky; the professor of the course trusts me enough to "let me loose" on the students every so often and I LOVE it!) is called "Plants as a Human Resource", or the equivalent of the Western version of Economic Botany at other universities and colleges. It's a great course, and one where, if the students care enough to pay attention, the information is not only incredibly interesting but also applicable to everyday life. They learn about where paper comes from, where their clothing comes from, where their food comes from, where the drugs that they take come from, where their beverages of choice come from, and how agriculture first started (along with a bunch of other topics interspersed along the way). It's a really fantastic course! Flax is one of the plants that the students learn about because it has been an invaluable resource to people all over the world for thousands of years. It was domesticated in the Fertile Crescent, an area that extends from Saudi Arabia all the way to Pakistan and India. This crescent-shaped area has been responsible for the domestication of many of our invaluable crop species, both plants and animals, like wheat, rye, cotton, flax, oranges, grapes, and opium poppies. Yes, opium really is an invaluable crop species! Think about how awful surgery would be if you couldn't be prescribed morphine, or even codeine? Both come from the opium poppy!

So why is flax such an important crop? It's not just for its nutritional value, as many people in North America today are aware of. Flaxseed is a great source of omega-3 fatty acids, which have been shown in some clinical studies to lower blood cholesterol levels. The evidence for this claim isn't strong anymore, since some studies have shown that the effect is stronger for women, while others have shown this effect is only noted in men. When clinical trials don't agree with each other, it calls all of the evidence for a specific claim into question. There has been another study that has shown that the consumption of relatively high amounts of ground flaxseed can stunt the growth of prostate tumors in men, but this has never been demonstrated in other clinical trials. Yet another study has shown that ground flaxseed can help people suffering from diabetes because it can stabilize blood sugar levels (another medical claim that has never been shown in another clinical trial). One thing that flaxseed definitely can do is act as a laxative when taken with water. The seeds of this plant contain an incredible amount of fibre, which acts as a "cleanser" for the large intestine. If excessive amounts of flaxseed are consumed without water, it will instead lead to intestinal blockage. There are other, more effective natural products used in laxative medications because they don't rely so much on water intake (such as senna, carob and tamarind) so ground flaxseed is rarely the main ingredient in herbal medications for constipation. Using ground flaxseed as a home remedy is strongly discouraged; if not enough water is consumed for it to be effective and intestinal blockage occurs, it can lead to death if not caught in time. Pardon the pun, but that would be a...poopy way to die.

Aside from its nutritional value, flax has been used for millennia for its other main use and for its other common name: linen. The stems of this plant contain bundles of fibres that run the entire length of the stem (up to 90 cm of useable fibre). They are easily extracted using a microbial decomposition process known as "retting", where the stems are essentially left to rot in the field. Microbes will decompose the parts of the stem around the fibre bundles, but because they don't have the ability to digest the fibres themselves they leave them alone. After a few days, the long fibres can easily be separated from the rest of the plant and they can be cleaned, dyed, and spun into thread or yarn. Linen fibres are very strong but very light at the same time, and much more breathable than cotton. Because the fibres themselves are so long, linen garments also resist wrinkling which has made them historically desirable for "travel clothing". So how long have we been using this plant for cloth fibres? Well, the answer to that question is now up for debate after a discovery in a cave in the country of Georgia. It was originally thought that linen was domesticated about 10,000 years ago and used sparingly prior to that time (the plant was much shorter, so producing cloth from the fibres was much more labor-intensive; the domestication process imparted characteristics of longer, larger fibre bundles in a taller plant), but bundles of fibres that were spun into thread, dyed, and tied into bundles was dated from the Georgian cave to be over 30,000 years old! That's some old thread. Ancient Egyptians mastered the art of spinning linen fibres into thread and using that to make cloth; all Egyptian mummies were wrapped in linen cloth. Unfortunately, the paper-making process has stripped "unimportant" mummies of their post-mortem clothing, as the first pulps used to make paper used linen fibres (and where the name "rag bond paper" comes from). I can only imagine how important paper must have been for people to go into tombs to steal mummy rags! Sounds like a creepy and gross job.

Aside from food and fibres, this plant also has a role in traditional herbal medicine, especially in Austria. There, it was used either as a tea-like beverage or as a oily skin compress to treat a whole slew of disorders from gout and rheumatism to asthma and the common flu. None of these medicinal qualities have ever been demonstrated in clinical trials, but if you think rubbing some fresh-ground flax on your skin will treat your rheumatism, go for it. It certainly won't make it worse!

Flax flowers are the national emblem of Northern Ireland, and the national flower of Belarus.

Pineapples don't grow on trees!

Today, being April 1st and all, I was going to photoshop two plants together and then "publish" a new species on my blog. Come up with a really creative name, pretend it has some ridiculous medicinal quality that I discovered while experimenting on my cat, and describe its ability to not only transport itself from one place to another by its roots, moving through sandy soil, but also that when the flowers open it moos like a cow. Yeah, big plans. But then you know what? I remembered I didn't have a clue how to use photoshop properly. Maybe I'll learn in time for next year's April Fools :)

Until then, 365 days from now, you can enjoy a (100% true) blog about...pineapples!

Species name: Ananas comosus

Common name: pineapple

Location: Dominican Republic

Pineapples. What to say about pinapples?! Well, the first thing to mention is that they do not grow on trees (you can read all about pineapple-like trees HERE). Pineapples are monocots; they don't have the ability to form wood and so cannot be a tree. Plus, from the first picture you should be able to see that they're more like a shrubby, spiky, rather dangerous-looking plant. This observation would be completely true; some of the people that were on the safari excursion with my mom and myself came away from the "farm tour" with scratches all over their legs from brushing up against pineapple plants. The leaves have razor-sharp spines all along both sides and they can slice through skin with the very lightest of pressure. Definitely a plant to stay away from unless you're wearing pants!

Pineapple plants are native to South America, at least that is the current school of thought. Very little is known about the actual domestication of pineapples, nor what the likely ancestor of a domesticated pineapple actually looks like. What is known is that the domesticated pineapple was introduced to the Philippines and to Hawaii very early on, likely before the days of Marco Polo and the Dark Ages. It seems as if no one could quite figure out how to propagate them, and they were eliminated from the agricultural crops of these locations until their re-introduction. It is said that pineapples were re-introduced in the 1500s to Hawaii by the Spanish, but this is widely disputed. We do know that they were cultivated there by 1720 in "pineapple pits", and a widespread re-introduction in the early 1800s caused them to be (and still are) one of Hawaii's most important export crops beginning in the late 1800s. In the Philippines, it is believed they were introduced sometime in the early 1800s, probably by the same Spanish ship that introduced them to Hawaii, and they have become a staple in rural Filipino life. The leaves contain very strong fibres with a very unusual texture (almost like silk when you run your hand along a garment in one direction and feeling like burlap in the other), and this has been used to make traditional clothing for at least two centuries. Now, pineapples are cultivated in the Philippines (mostly just exported to other areas in Asia and in Australia/New Zealand), Costa Rica (where Del Monte produces all of its pineapples after the breakup of the Pineapple Research Institute in Hawaii), the United States (where Dole still grows a lot of its pineapples), Thailand, and Indonesia.

Pineapples carry a lot of controversy, especially with the methods used to cultivate them. Pineapples are all clones of each other; that's the only way you can ensure the fruit obtained will be the same sweet, juicy pineapple consumers have come to love and expect when they buy pineapples. Unfortunately, whenever you clone a plant you make it unable to evolve resistance to pathogens, and pineapples today are attacked on a daily basis by fungi, bacteria and viruses that have evolved virulence genes against the plants. In order to fight disease, this means pineapple plantations must be sprayed, sometimes upwards of 40 times over the time of fruit development (which is only 6 months), just to prevent disease. The chemicals sprayed on pineapple plantations are incredibly dangerous to the health of the workers on the plantations: every chemical sprayed is carcinogenic, many are organophosphates which destroy the environment and can affect brain development in fetuses, and some are hormone disruptors which can have adverse effects on child development (they have been linked to everything from autism to attention deficit disorder to spontaneous miscarriage, brain cancer and leukemia). These chemicals aren't just dangerous for the health of the workers that spray the fields and work in the fields all day; these chemicals are leached into the drinking water supply and are consumed downstream by everyone in surrounding villages. This is a real problem, and there have been many lawsuits filed against both Dole and Del Monte along with encouragement to solve this problem by working harder to develop different cultivars that are disease resistant. There is some effort underway in pineapple biotechnology, but because of the "bad rap" that genetically modified food has, none of these products have made it to widespread cultivation. Remember, too, that if a chemical is sprayed onto the surface of a food item, it is more than likely incorporated in some way (however large or small) into the food that is consumed. Some food for thought (pun intended).

Pineapple fruit develops in a very unusual way; a way that is not shared with any other fruit commonly consumed worldwide. It is called a "multiple" fruit, because it is a single fruit made from multiple flowers. The entire inflorescence of the pineapple goes into making a single fruit! Each flower must be pollinated, usually by bees or hummingbirds, and then all at the same time the flowers mature into the pineapple. The actual pollination process can take from 20 to 24 months! That's two years just to get the beginning of a pineapple fruit. That gives me a whole new appreciation for my pineapple. After all of the flowers have been pollinated, the fruit takes another six months to become fully mature. In the third picture, you can see some of the flowers emerging from the inflorescence. Unfortunately, this entire process is actually detrimental to pineapple production since flower pollination implies seed production. No one wants to be eating seeds in their pineapple! For this reason, pollinators of the pineapple plants have been banned from import by the Hawaiian islands, to prevent unwanted seed development. If no pollination occurs, the fruit still develops but just no seeds are formed. The pineapple is said to be a "mathematical" fruit; the flowers are arranged in two spirals around the inflorescence stalk, with one spiral going each direction. If you count the number of flowers in a spiral one direction it's 8, and the other is 13. This means that the pineapple is an example of a fruit in nature that displays the Fibonacci number sequence. Neat!