Monday, December 31, 2012

Flamboyant Flamingo Flowers

Species name: Anthurium sp.

Common name: Flamingo flower

Location: UWO Greenhouse

The common name "flamingo flower" actually refers to an entire genus of plant species; Anthurium is estimated to contain 1000 or more species with almost all of the diversity of this genus existing in the South American tropics. There are a few exceptions, but none of them are notable. Approximately 3/4 of the species known in this genus are either threatened or endangered due to habitat loss, which makes the entire group incredibly vulnerable to extinction. These flowers are actually remarkably difficult to grow from seed in a greenhouse, so plants in some locations were hunted almost to complete eradication for the international tropical plant trade. Now, ornamental species are grown in greenhouses and propagated from cuttings, which means two things: first, they are no longer collected in the wild (or at least very little wild collection), and second the populations grown in cultivation are all genetically identical. This could be devastating for the flower trade (and once again for the wild Anthurium populations) if there was a pathogen that invaded greenhouses and flower plantations and wiped out all of the plants because they had no resistance.

The Anthurium flower, like the Jack-in-the-Pulpit flower (which you can read all about HERE), is a specialized type of flower. Anthurium species break all the rules when it comes to determining if a plant is a monocot or a dicot. Monocots have flower parts in multiples of 3s, and have long, narrow leaves with parallel veins. Dicots have flower parts in multiples of 4s or 5s, and have wide, broad leaves with net-like veins. Anthurium is a genus of monocots with broad leaves, veins that are somewhere between parallel and net-like, and have one inflorescence made up of tiny flowers that have their flower parts in multiples of four. Someone should tell these plants that they need to read more botany books to learn the rules! Anthurium flowers are made up of two parts: the spathe, or the white shield-like petal surrounding the rest of the inflorescence (its role is to attract pollinators), and the spadix which houses all of the tiny little flowers (thousands of them less than 1 mm across!). On the bright side, we've made up a new rule concerning the ways to tell monocots and dicots apart when the plants refuse to read books: whenever you see a plant with an inflorescence made up of a spathe and spadix, it's always a monocot!

Sunday, December 30, 2012

For all you caffeine addicts...

Species name: Coffea arabica

Common name: coffee

Location: UWO Greenhouse

I was contemplating skipping this plant and blogging about it later when I finally found my pictures of wild coffee plants growing in Cuba, Dominican and Jamaica, but then decided that no, I'll just make it two blogs! Ah, the joy of being my own boss...

Despite coffee being grown in multiple locations around the world (with Colombian coffee gaining the most press recently as being the most prolific source of the world's coffee), it is actually incredibly rare in its native habitat in Ethiopia. There are some protected natural populations, and some equally protected populations in neighbouring South Sudan (no one is quite sure if that is a native population or a population that was introduced there very early on in the domestication process). There is also one very old population in Kenya, but it is believed to have started there as a result of trade with Ethiopia hundreds of years ago and not an independently domesticated population. Due to climate change, the "growable range" of coffee is shrinking. It requires cool, humid climates usually on mountain sides. There have been many attempts to grow coffee in North America in the great outdoors, but every single one of these ventures has failed. Coffee is very sensitive to rainfall, and if it is in an area with too much or too little rainfall it will not survive. To say it's a finicky plant would be an understatement! It is possible that with further climate change the Rocky Mountains or the Alps might one day be hospitable for coffee growth, but by then we will have significantly more problems than just not having coffee!

Believe it or not, the British used to be avid coffee drinkers, not tea drinkers. So what happened? Well, one of the areas of the world during the British Empire that was the most productive for coffee was Sri Lanka, then called Ceylon. Unfortunately, there's a fungal pathogen of coffee called the coffee rust that was spread from Ethiopia into Yemen and then to Sri Lanka that completely destroyed their coffee crop since it had no resistance (native populations do have some resistance to this pathogen; we have also now developed fungicides and genetically modified crops that show much higher resistance). The British noticed that the Chinese and Japanese made a beverage very similar to their coffee drink, and decided to "borrow" some of their crop to replant Sri Lanka. The British had discovered tea, and have been tea drinkers ever since (and tea is still the leading export of Sri Lanka, even 400 years later!). Tea and coffee, the main sources of the drug caffeine, are the most consumed beverage around the world. One could argue that caffeine is also the most abused drug in the world!

Friday, December 28, 2012

Doesn't look like a donkey tail to me!

Species name: Sedum morganianum

Common name: burro's tail

Location: UWO Greenhouse

As you may or may not be able to tell, the group of plants for my last few blogs were all native to Mexico and the surrounding area and this plant is no different. Burro's tail is native to southern Mexico and into Honduras, where it is incredibly common. This plant is also a very popular houseplant in hanging baskets (as is growing in the greenhouse, but it can also grow along the ground), and can survive in some areas in the southern United States. It is drought-tolerant due to its fleshy, water-storing leaves, and can actually be damaged very quickly by over-watering. Watering once a month during the non-flowering season and once a week or every two weeks from spring to summer is more than sufficient. I tried growing this plant once and managed to kill it in 7 days; a record for me. It was sitting on a heater in the window, one of the only places I had in my apartment to grow plants. Ironically enough, if I hadn't of watered the plant almost daily because I thought the soil was getting too dry being on the heater, it probably would have thrived and taken over the entire living room! Lesson learned: when you get a new houseplant, look up how to care for it on the internet!

This plant is an interesting lesson in Spanish and English translations. The other common name for this plant is "donkey tail", and "burro" is the Spanish word for donkey. There is another cultivar that is very commonly grown as a houseplant called the "burrito" cultivar. Did you know that a burrito is a baby donkey?! You can probably imagine how this cultivar is different from the species growing in the wild. I will never be able to look at a burrito while eating dinner the same way again...

As with many of the plants featured from the greenhouse so far, please exert extreme caution should you choose to grow this plant indoors and have cats. The plant is incredibly toxic to humans and other animals alike, but due to its growth habit this plant looks especially like a cat toy hanging off a table. Even ingesting one leaf of this plant could seriously harm the digestive system of a cat or small dog, and the plant is prone to losing leaves on its own.

Thursday, December 27, 2012

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.

Tuesday, December 25, 2012

A special Christmas ecosystem

Today, with it being Christmas and all, instead of profiling a plant in my blog I figured I would profile an entire ecosystem. This ecosystem is incredibly rare, only occurring in one tiny pocket in the world, and I've been lucky enough to visit it yearly. It's a hidden gem; I can guarantee that none of you have ever seen it before, although many of you will have experienced something similar. Unfortunately, it's a transient ecosystem and is best experienced at this time of year. It's also almost like it has a timer; almost every year on New Year's Day it disappears for another 11 months. Strange! I'm not going to tell you where this ecosystem is since I like to keep SOME secrets (and my mom is mad enough about her stuffing recipe!). So enjoy the photo collage with explanations! :)

Species name: Abies navidadea

Common name: artificial Christmas tree

Location: secret!

The first species I'll profile from this ecosystem is known commonly as the "artificial Christmas tree". I'm not sure how the common name came about; it's either going to be a Christmas tree or it's not. But we'll go with it for now! This species grows incredibly quickly but never achieves its full height, rarely growing above 5 feet tall. It has intimate associations with other species, which I'll talk a bit about as we come to them. Unfortunately, the wood of this species is incredibly tough; it can be compared to solid steel. This makes it incredibly impractical for any use other than ornamental use.

Species name: Bacillus fibreopticaleus

Common name: fibre optics

One of the reasons why this ecosystem is so endangered is because of the poaching of trees that occurs for the symbionts that live within the trees themselves. Commonly these are called "fibre optics", a species of bioluminescent bacteria that live within the branches and on the surface of the needles. Why these species exist on and in the tree no one is quite sure; it might act as a way of attracting insect pollinators. The cones that grow on this tree in the spring (usually when the ecosystem is hidden away for the year) are incredibly unusual as far as gymnosperm cones go; the pollen isn't wind dispersed like other pollen cones. It is hypothesized that there were once insects that had co-evolved with these trees, attracted by the bioluminescent bacteria, that once pollinated them. It is also hypothesized that these insects have long since gone extinct or are hunted to near extinction by the ever-dominant Homo sapiens.

Species name: Gymnosporangium navidadea

Common name: Christmas ornaments

Unfortunately, the artificial Christmas tree is often attacked by a very unusual species of fungus, one that has a complex morphology like the cedar apple rust (and so it is placed in the same genus; no DNA analysis has been done on this species so we are unsure of its correct placement within the fungi). The morphology of this species is very similar microscopically to a pipecleaner with a very rigid interior and a fluffy, polyester-like exterior. The six arm-like projections are thought to mimic snowflakes, but we are unsure whether or not this has any kind of biological relevance. A very unusual species, indeed!

Species name: Sphagnum treeskirtii

Common name: Tree skirt

This species of Sphagnum grows almost exclusively with artificial Christmas trees, although it can occasionally grow with other species used as Christmas trees in captivity. It has an incredibly soft, fur-like texture that is sometimes pressed into large sheets of fabric and sewn to make seasonal clothing; it is believed that Santa Claus wears a suit made of this botanical fabric (but no one has ever seen it to confirm this idea). Other uses for this type of moss is unclear; it is rumoured to have a role in animal bedding in captivity.

Species name: Ursus noelae

Common name: Christmas bear

As an incredibly unusual step for my blog, I figured I can't possibly ignore the last integral part of this special ecosystem even though it happens to be an animal. This bear is very unusual, not just because it's one of the only bears to have ever worn clothing on a regular occasion. The main reason for why it is so unusual is because of its size; it's barely 4 inches tall! Another unusual characteristic about this bear, the only one that has this characteristic in the genus, is that it is a herbivore. It grazes on the needles and bark of the tree, rarely leaving the tree that it also uses as shelter (it is rumoured to build a nest in the tree like birds do; I have never seen this phenomenon in action so I can't speak to the validity of this rumour). Unfortunately, this is the most popular prey of a very large cat-like creature, commonly known as Storm The Cat (Latin name Felis catus). This cat subspecies (it is believed to be the only one left) is a ruthless predator when it comes to the Christmas bear, tearing it from its tree and throwing it to the ground. It does almost seem to be a game, however, as rarely does the cat do anything to the bear after this. Nevertheless, the bears are often so scared that they have heart attacks, leading to their population numbers suffering needlessly as a result of this "game" played by the cat. She is discouraged, but likes to hunt at night when no one is watching. We have considered erecting a fence to protect this fragile ecosystem...

Merry Christmas, everyone!

Monday, December 24, 2012

The dense-leaved asparagus

Species name: Asparagus densiflorus

Common name: asparagus fern

Location: UWO Greenhouse

Like many common names, the common name for Asparagus densiflorus is incredibly misleading as it is not a fern. It probably gets the common name due to its feather-like foliage, and in some cultivars it does greatly resemble a fern (having been bred for short branches instead of the 50 cm or larger branches that can occur in the wild species). The asparagus fern is native to Africa, in a region from Mozambique south to South Africa. Both this plant and a very close relative, A. aethiopicus, are very common greenhouse plants, houseplants, and landscaping plants. Contrary to popular belief, the asparagus fern is not invasive in the southern United States, where it can survive being planted outdoors year round. It is unfortunately commonly mistaken for other close relatives, which ARE invasive and can be a menace to native flora due to the incredible network of underground rhizomes from which the upright stems grow. Once established, certain Asparagus species can be darn near impossible to eradicate, and most are resistant to RoundUp (remember that RoundUp is a broadleaf defoliant; Asparagus is a monocot and not a broadleaf plant so it should not be surprising that it is largely unaffected by this common herbicide!).

The main use of this plant and its very close relatives is as greenery in floral arrangements. Any kind of feathery green foliage that you get when you buy flower bouquets are probably the "fluffy" cultivars of A. densiflorus or A. plumosus.

Like many Asparagus species, this plant can have very sharp spines along its stem which can wreak havoc on clothing and skin. It produces white to pink flowers which mature into red fruit; the juices from the fruit are toxic and so should not be consumed. When the leaves are crushed they can also irritate the skin in much the same way that poison ivy does, but the irritation is much shorter lived (only about 20-30 minutes or so). Despite being relatively benign to humans, consuming any part of this plant will kill a dog or a cat, so if you do grow it as a house plant make sure your animals stay away from it!

Saturday, December 22, 2012

Ferns as brooms

Species name: Psilotum nudum

Common name: whisk fern

Location: UWO Greenhouse

The whisk fern is in a genus of only two species, one of which is endangered throughout its native range. This species, the "naked" whisk fern, is native to southern Japan but now grows through much of the tropical and subtropical world. It is epiphytic, meaning that it can grow off of substrates other than bare earth, usually other plants (it can even grow on rocks and extract nutrients from the passing air currents and in rain water). It is even known to grow on unused power lines in some areas in Africa! When growing on other plants, it is rarely parasitic and instead just uses it as a prop.

Whisk ferns do get their common name from their most common use: as brooms. The branch-like appendages of the fern would be tied together (unlike most common ferns, the stems are actually quite tough and rigid) then attached to a long stick and used to sweep debris. Aside from the obvious use for this plant, there is at least one use that I was surprised to learn about employed by the Native Hawaiian people: as talcum powder. The spores were collected in bowls, and then used on the skin under loincloths to prevent chafing.

Because of the fact that these ferns are perennial species that are incredibly long-lived (even when you don't just compare them to other species of ferns), there has been much interest in the types of secondary compounds produced in the stems (which are actually modified leaves). There has been the suggestion that the whisk fern might be a goldmine of new antibacterial and antifungal chemicals that could be used in agriculture or medicine.

Friday, December 21, 2012

Kusamaki: the Arhat Pine

Species name: Podocarpus macrophyllus

Common name: Buddhist pine

Location: UWO Greenhouse

Podocarps are native to a region from China all the way south to the northern tip of Australia. This particular species is native to a small region in China and Japan, but is incredibly abundant there even now. Since the name "Buddhist Pine" is incredibly misleading (this plant is not a pine!), the traditional Japanese name is being favoured by English-speaking countries as the new common name of this plant: Kusamaki. In nature this tree can reach up to 20 meters in height, but in a greenhouse it rarely reaches more than a couple meters.

When mature, the Kusamaki produces berry-like structures that are used to disperse seeds, much like the yew (which you can read about HERE and HERE). They are toxic to humans (definitely won't kill you, but certainly will make you regret your decision to consume them), but quite delicious to birds who eat the fleshy coating of the seeds and disperse the seeds themselves in their poo. This phenomenon a very common bird-plant relationship, with many species of plants actually requiring their seeds to pass through a bird's digestive tract in order to germinate. While in the bird's gizzard, the sand that they consume to help grind their food to a paste also lightly scours the seed coat, which allows  it to pop open once exposed once again to sunlight, organic material and water. This is called ornithochory (ornitho- for "bird" and -chory for "to spread/disperse").

The Japanese rely very heavily on this plant as a building material, as many traditional Japanese houses are still made out of wood and must be resistant to rain and strong against wind. The wood of this plant is very rot resistant, and has its own waterproofing. The other desirable characteristic about this plant is that it is very resistant to termites, a huge problem for some prefectures or states in Japan. In Hong Kong, the Kusamaki is regarded as one of the most prized trees for feng shui, which means it is very valuable for sale and trade. In some areas in Hong Kong, the tree has been hunted to near extirpation due to the high market value for mature specimens.

Thursday, December 20, 2012

The Purple (not a real) Shamrock

Species name: Oxalis triangularis

Common name: Purple shamrock, love plant

Location: UWO Greenhouse

The purple shamrock, not a real shamrock, is native to Brazil. One of the most exciting features about this plant aside from its purple foliage is that the leaves open and close as a result of sunlight and also reportedly a change in temperature, although it's difficult to say what is the cause for the movement in the leaves (since the temperature drops when the sun sets; it's a chicken-and-egg conundrum).

Unfortunately, the images of this plant show a rather unhealthy potted plant; there's a bit of an aphid problem in the greenhouses. This is also indicative of the problems that many homeowners have when trying to grow this plant indoors: if there's an aphid anywhere in or around your house, it seems like it will seek out and destroy any shamrocks within 5 square kilometres. It's actually quite impressive when you think about it. Even more impressively, in the wild these plants seem to be completely unaffected by aphid herbivory. It seems to only be a "problem of captivity," if you will.

One great characteristic of this plant is that it is 100% edible. They have a rather...pungent taste, that to me isn't very pleasant. But they would be great in a mixed greens salad, and the flowers are great for decorating salads, cakes and cupcakes. A multi-use tropical indoor plant! Make sure you don't eat too many leaves, though, as they do contain moderate amounts of oxalic acid, which can irritate the lining of the digestive tract. Unless you have kidneys operating at a reduced level of filtering function (due to kidney disease, diabetes, or other disease that affects the kidneys), poisoning from this plant leading to serious illness or death is nearly impossible. You would have to dedicate every minute of every day to eating it! The purple shamrock also does well outdoors in USDA growing zones 8a to 11, which roughly corresponds to an area from South Carolina all the way west to Texas and into Mexico, then south all the way to the Florida keys. If you live in these areas and choose to plant it outside, do take care since they tend to have a weedy growth habit and can strangle out other plants nearby.

Tuesday, December 18, 2012

The plant version of bubble wrap

Blog update: My apologies for not posting as regularly during the month of December as I usually do. I have been running close to the end of the photos I took on my last plant photography bonanza in September, and couldn't come up with an idea for where to go to take pictures of plants to blog about during the winter months that would look like more than just sticks. Then the idea hit me. The greenhouse on campus! Starting tomorrow I have a whole bunch of tropical species to blog about, courtesy of the UWO greenhouses. Very few if any of them will be native species, but some of them are incredibly interesting and unusual (I've been doing my homework!) so I think you'll all enjoy learning about them. I will also be running a series of blog posts about "How to Identify Sticks" once the winter really sets in, so stay tuned for how to identify woody plants during the winter months.

Species name: Impatiens glandulifera

Common name: Himalayan balsam

Location: Ontario

The Himalayan balsam, as the name suggests, is originally from the Himalayan region in Asia. The plant is a temperate plant, growing very happily on mountain sides up to the tree line, but preferring areas closer to the base of the mountains. Unfortunately, it is one of the most dangerously invasive plants in North America and Europe, where its introduction (sometimes purposely as an ornamental and/or medicinal plant, other times by accident) has completely destroyed the understory of many forests previously dominated by native species. This plant can grow so large so fast that even garlic mustard (which you can read all about HERE) has a rough time competing with it. The stems of this plant are incredibly unusual; they are hollow between the nodes and completely filled with fluid. More on this later...

Another unfortunate characteristic of this plant is the seed dispersal mechanism contained in the ripe fruit. There's a good reason why this plant is called the "touch-me-not," and it has nothing to do with it being toxic on the skin. The fruits have a ballistic mechanism that forcibly discharges the seeds when touched (and when the fruit is ripe). This isn't an unfortunate characteristic for the plant itself; it actually ensures for incredibly successful seed dispersal. This is an unfortunate characteristic for environmental health in areas where the plant is not native. Have you ever had the opportunity to play with the fruits and get them to release their seeds?! If not, it's quite the experience. You touch it and it feels like something just exploded in your hand and seeds go flying everywhere! It's fantastic! And that's the exact reason why it's so unfortunate: in populated areas, the main reason for successful seed dispersal is due to...children! It's just as entertaining for kids (and some adults. Guilty as charged) to force the plant to release the seeds as it is to give them a sheet of bubble wrap and watch them occupy themselves for hours.

Once established, this plant is incredibly difficult to eradicate but there's a company in Germany that just might have found the secret to getting rid of it. They are busy developing a wide array of products made from the flowers of the plant, in hopes that the picking of the plant for profit will eventually contribute a financial means for its eradication. A brilliant idea, and I hope it works out for them. We could definitely use something like that in southern Ontario!

Apparently all parts of this plant (including the flowers, which are incredibly attractive) are edible. I've never tried it, but I have seen flowers of this species adorning wedding cakes. I haven't actually seen anyone try to eat them, usually they're picked off and left on the plate as a non-edible decoration. I have, however, greatly enjoyed the medicinal use of this plant on many occasions. The liquid contained in the stems is incredibly effective at soothing itchy, dry skin due to any cause. It will take away the itch associated with a poison ivy rash almost instantly (which even calamine lotion can't do!), relieve the itch of mosquito bites, take away the sting from bee and wasp stings, moisturize dry skin, and soothe the itchy pain of sunburns. Because the plant is non-toxic, it's even safe to use on your face, but make sure you don't get it in your eyes. Just because it's safe for your digestive tract doesn't mean it won't irritate the sensitive tissues of your eyeballs! And, like with all plants, before you consume or otherwise use this plant in any way, make sure you are absolutely certain of the correct identification. The leaves look slightly like stinging nettle leaves; you would NOT want to confuse the two in an attempt to soothe a poison ivy rash!

Saturday, December 15, 2012

A Rocky Mountain Juniper

Species name: Juniperus scopulorum

Common name: Rocky Mountain juniper

Location: Ontario

As the name suggests, the Rocky Mountain juniper is native to the Rocky Mountains in North America, from British Columbia all the way south into Mexico (although, there are so few populations left in Texas and Mexico that the range should probably be amended to say it ends in Arizona; this very suggestion has been put forth by the USDA more than once). It thrives in high altitudes where it is common and a relatively short tree (as most alpine species are), but incredibly long lived. In New Mexico, one was felled that was estimated to be 1,500 years old, and a standing dead tree was found to have 1,888 tree rings. There are some individuals left in Arizona that are estimated to be 2,000 years old or more. Incredibly enough, these aren't even the oldest living trees on Earth...

Those of you who live on the west coast and have seen this species in their native habitat on mountain sides will probably be pretty jealous of the height of this individual on campus. It was probably planted when Talbot College was built in about 1970, so the tree would only be 40-50 years old. It's already much taller at 50 years than other individuals would be after 750 years or more! Just goes to show that when you plant species outside of their native habitats, strange morphologies can be achieved.

Like all gymnosperms, the "berries" produced on the branches are not fruits, no matter how they might appear. Gymnosperms, unlike angiosperms, do not have flowers and so don't have all the layers of tissue required to produce a true fruit. Despite this fact, ginkgo (which you can read about HERE), yews (which you can read all about HERE and HERE), and junipers all produce berry-like "fruits" that are just modified seeds. The outermost layer of the seed is modified to store starchy and sugary compounds, often with a lot of waxes and resins to protect the seeds from predation by small animals, and are produced instead of cones. Another interesting fact to note about this species of juniper is that, like ginkgo and holly, the tree is either male or female but never both. The bright blue modified seeds are produced on the female trees, and the male trees have pollen cones that are produced in the spring and release all of their pollen into the air right around spring allergy season. It seems like in the spring and fall, all of the trees conspire against humans to irritate our airways! Sometimes the blue berries are produced regardless of whether the male tree is present or not, but the seeds inside will not be viable. Like holly and ginkgo plants, if you want to ensure the success of the seeds you need to plant both sexes in close proximity.

Many junipers have traditionally held a strong importance in the lives of native North Americans due to their medicinal value. The bark of the Rocky Mountain juniper is boiled to make a tea and consumed to treat coughs and fevers. Since there are so many resins produced by this species (the yellow "sap" that drips down the outside of the tree, especially after the tree has been wounded) have great antimicrobial properties, and are actually the very reason the tree produces them in the first place! I have strong suspicions that any time the bark of a gymnosperm is cooked to extract the resins then consumed, it will have a strong effect against bacteria in the mouth and throat. This doesn't mean you should attempt this, however; some resins produced by various species of gymnosperms are highly toxic and should never be consumed! It's always a fine line in herbal medicine between things that will make you very ill and things that will help your sickness. Mixing your own concoctions just to try things out is strongly discouraged.

Thursday, December 13, 2012

A cold-tolerant eucalypt

Species name: Eucalyptus gunnii

Common name: cider gum, eucalyptus

Location: Ontario

For anyone from Australia, to see any eucalyptus plant in Canada outdoors would probably be surprising. In fact, it's not just Australians that would be surprised; this Canadian was mighty surprised, too. I was shocked to see that the campus landscapers would have thought this plant was going to survive in our climate, which is inhospitable to tropical trees to say the least. To my surprise, the more I read about this plant the more I wanted to put one in my back yard for novelty sake; it's actually incredibly cold tolerant! This species of eucalyptus will readily survive winters with extended periods below -10 degrees Celsius, and can even survive short periods below -20 degrees Celsius. It's still not a good idea to trust this plant to a harsh Canadian winter, but finding out it could survive snow cover was a surprise to me. This is actually becoming a popular garden plant in Europe since it has the attractive evergreen foliage of a eucalyptus (and the incredible smell) while not having to be taken indoors every winter.

All eucalyptus trees are native to Australia and the surrounding area, but most have been successfully transported outside of this restricted area for ornamental and medicinal use. This particular species, the cider gum tree, is native to a very small area in Tasmania. Like Madagascar periwinkle (which you can read all about HERE), there are few individuals left in the wild in its native range, despite being so incredibly common in other locations in the world due to its ornamental value.

One spectacular morphological characteristic of this plant that is rarely seen to this degree in nature is the morphological variation of the leaves along a single branch. The leaves start off almost circular, with a very short (sometimes absent) petiole at the base of the leaf. The leaves spiral around the branches of the tree, and are a brilliant grey-green. As the branch grows longer, the leaves also elongate until they look very similar to willow leaves, and there is a change in colour so the leaves are a much darker, deeper green. If the tree is pruned into a shrub (as is most common in an ornamental plant setting), the shrub will retain its juvenile leaf form and never progress to having elongate leaves.

While this species of eucalyptus is not often used for anything other than as an ornamental plant, other species in the genus are used for their essential oils, which are very powerful antibacterial chemicals, insecticides, and even industrial solvents. The oils are sometimes also added to food, but only in very minute quantities (the saying "a little goes a long way" is absolutely true in the case of this plant, but also even moderate amounts of the essential oil when consumed is toxic to humans). The tree's leaves are the main food source of the koala, an animal often regarded as the "icon of Australia". Eucalyptus trees are also known as "water-suckers" since they can completely dry up a swampy area in only a few years, turning the soil into arable land. This doesn't last long, however, and the land quickly converts to desert after only a few growing seasons. The wood of eucalyptus trees is very quickly produced, and so it was once considered as a biofuel before being abandoned for other crops that were easier to care for.