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.

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.

One of the Austrian pines

Species name: Pinus nigra

Common name: Austrian pine, European black pine

Location: Ontario

The Austrian pine is native to Europe, in countries surrounding the Mediterranean and Baltic Seas. There are actually two subspecies of the Austrian pine which rarely interbreed (but are still capable of forming hybrids in a very small overlapping zone as well as when they are brought together under artificial conditions like a greenhouse): the western subspecies existing in southern Italy, southern Spain, southern France and North Africa and the eastern subspecies in Austria, central Italy and Turkey. The needles of the two subspecies are quite different and you can easily tell them apart when side-by-side; the needles of the eastern subspecies are much fatter and much more rigid than the western subspecies. They both have different liveable temperature ranges, too, with the eastern subspecies being able to tolerate much colder minimum temperatures (down to -40 degrees Celsius with no adverse effects) compared to the western subspecies (only about -25 degrees Celsius or so). I believe the subspecies on campus would be the eastern subspecies, P. nigra subsp. nigra.

One major attractive feature that probably led to its widespread planting across Europe and North America is that it is a very fast growing tree, relative to other needle-bearing trees. It was originally thought to be an excellent lumber tree, so it was planted in large numbers in North America. Unfortunately, the grain of the wood is very rough and quite variable across the height of the tree, so making long boards suitable for building is not feasible. It was turned to as a major source of pulp and fibres for making paper, as a fuel source, and is still used as a low-grade wood for some construction purposes.

Unfortunately, as with most plant species that have been transported out of their native range, the Austrian pine has a dirty secret. That secret is a fungus. The "red band needle blight disease", caused by the fungus Dothistroma septosporum, is especially toxic to North American Austrian pine trees because of their inability to breed properly here. Austrian pines have a hard time cross-breeding outside of their native ranges, and the seeds that are self-fertilized are much less likely to germinate. This causes something called "inbreeding depression," which can lead to a buildup of genes that make a tree (this happens in animals, too) more susceptible to a pathogen. The North American trees are very susceptible to this pathogen, and it is an almost certainty that every single Austrian pine tree in North America will succumb to this disease. There is no known treatment once a tree is infected other than cutting it down and burning the residues (especially the needles, where the pathogen is housed in the living tree). Planting this tree, even as an ornamental, is strongly discouraged and planting this tree in continuous stands is not only strongly discouraged, but carries quite a hefty fine if you're caught doing it in many states in the United States (but no provinces in Canada yet). You can see that the tree in the top picture is looking very unhealthy; it is likely showing the first signs of infection from the disease.

The Japanese can't make their own taxol from their yew

Species name: Taxus cuspidata

Common name: Japanese yew

Location: Ontario

You might be wondering why I'm featuring the same plant twice in the same week, but you would have made one vital assumption that is incorrect: just because two species look the same doesn't mean they are the same. The Japanese yew, featured here (native to Japan, as you might have guessed), is a very close relative to the Canada yew, featured in my blog post on Monday (read all about it HERE). In fact, by assuming that the photos above represented the same species as that of the Canada yew, you would be making the same error that many botanists have made in the past; it was only recently demonstrated that there are distinct species within the genus Taxus. The genus was originally thought to be monotypic, and instead having distinct geographic races or subspecies that are on their way to becoming their own species, but have not yet become distinct enough to warrant the title. The Sumatran and the Mexican yews are the most different from the type species, the European yew. These were the first to obtain their own species designation, with every other species following suit and being confirmed through DNA sequencing.

So if these species are so morphologically similar, how do you tell them apart? Well, the needles and their arrangement on the branches is the first clue. The needles of the Canada yew are arranged around the branches when young, but the development of the bark on the branches almost flattens out the arrangement of the needles as it matures. If you look at the branches that are brown in colour instead of green (showing that bark has been formed), the needles are in two rows on each side, but are flattened on the branch. It has almost become two-dimensional. The difference in the maturation of the Japanese yew branches is that the needles remain spirally-arranged on the branch; they never flatten out unless something has been grazing the branches. With age, the needles also turn upwards, so all of the oldest needles on the inside of the shrub or small tree are pointing upwards, even though their point of attachment on the branch is all the way around it.

The second hint that these are different species is their sheer size difference. The Canada yew barely reaches a height of 2 meters off the ground and completely lacks a central stem. While the Japanese yew pictured above doesn't really look like it has a central stem, it is clearly more "tree-like", and the branches have the ability to support their own weight as opposed to drooping onto the ground like the Canada yew branches do. The Japanese yew can also grow to a maximum height of 18 meters.

The last major differences are not visible to the eye, but rather "visible" to a machine called a gas chromatography mass spectrophotometer, or GCMS. These machines are also sometimes called the "mass spec," and if you watch CSI at all you will have heard of them! They really do exist, and they are used in much the same way as suggested on TV (but not nearly as quickly, and the results are a bit harder to interpret than what the shows make them out to be!). You dissolve a bit of an unknown substance into a solvent (usually some sort of alcohol, although other organic solutions are sometimes used like chloroform), and inject a very small quantity into the machine. The machine separates the individual components of the liquid mixture by molecular size, and displays a graph of molecular weight versus abundance. The shape of the peak tells you what types of chemical bonds are present, and the location along the size axis tell you how big the molecules are. The height of the peaks tell you how much of any given substance are present. So what does this have to do with the Japanese yew? Well, it's a rather unfortunate tale for the Japanese; if they want to make their own paclitaxel, they're going to have to start planting Canada yew. The Japanese yew doesn't contain the right combination of taxanes to have the desired medical effects. In fact, the Japanese yew is exponentially more toxic than the Canada yew; it has the distinction of being the "Japanese horse killer." Just five needles are enough to kill a small dog. If you choose to plant this ornamental tree in your garden, please keep animals and small children away from it! And don't EVER use it as a Christmas tree!

The fern with the maiden's hair

Species name: Adiantum aleuticum

Common name: western maidenhair fern

Location: Ontario

Unlike many ferns popular to grow in North America, this one is actually native to most of Canada and Alaska. It is incredibly cold-hardy as far as ferns go, surviving much colder temperatures than any of its ferny relatives. There is another species, A. pedatum (the five-fingered fern), that is also native to North America that is equally cold hardy and was once thought to be part of the same species (they were shown to be different species through DNA sequencing in 1991). It has slightly different fronds that are darker green than this species, and is a bit shorter when full-grown. Both species are deciduous, meaning the fronds are shed during the winter, but a few of their relatives are evergreen species, even in colder climates.

Also unlike many of its ferny relatives, this species' conservation status is listed as "secure" in all areas of its native range. I find this somewhat hard to believe since we're destroying its native habitat at a rather unprecedented rate, but they're the experts so they know what they're talking about. Part of the success of the species is thanks to its attractiveness; this is also an incredibly popular fern to grow as a landscaping plant in gardens. There are some very similar Chinese and Australian species, though, so if you choose to grow this in your garden make sure you're choosing one of the two native species. Because ferns are so sensitive not just to habitat change but also to climate change, they are at greater risk of extinction than any other plant species. When the dinosaurs ruled the earth, ferns were the dominant plant species; the majority of the "trees" that flying dinosaurs would have made their nests in would have been ancient species of ferns! There are still a few "tree ferns" that exist today, but nothing nearly as majestic as a 75-100 foot tall fern tree. They're much smaller at only 6-10 feet at their maximum.

Maidenhair ferns have been used as a medicinal tea plant for hundreds of years by Native North Americans. It is said to help relieve mucous membrane irritation, and so was often consumed to help sore throats and colds. Since we now know that even just drinking warm water will soothe a sore throat, drinking a tea with maidenhair fern leaves should be surprising that it would help a sore throat. Whether it has any actual medicinal value other than the placebo effect has yet to be determined.

The "little sister" pine

Species name: Pinus resinosa

Common name: Red pine, Norway pine

Location: Ontario

Surprisingly enough, the common name of this species is not reflective of its natural heritage. Sure, it's an economically important tree in Norway, but it certainly didn't originate there and more than likely wasn't first discovered there, either. The red pine is native to Canada and the northeastern United States, is the state tree of Minnesota, and is much smaller in almost every respect compared to the eastern white pine.

It is relatively uniform in its morphology, so you'll rarely see "exceptions" to the general shape, size, colour, and rate of maturation of any one member in a population. This would suggest that each member of the population is very genetically similar, and that each copy of each gene has few alleles (and perhaps only one allele expressed in two copies). How does this happen? Well, there's only one way: near extinction. This very concept has happened recently with the cheetah and also the eastern cougar. The populations are so genetically uniform that very strange genetic deformities are starting to appear more and more commonly in the population. In a "pristine" population, one that hadn't gone through a near-extinction event, genetic diseases are rare and you usually need two copies of a gene to express the disease. If you only had one copy, you would appear normal, and no copies you would appear normal and any children you had would also appear normal (since no matter what genes they get from your mate, you will be passing on one of your two normal copies of the gene to your children). Because an individual with one normal copy and one recessive copy appears normal, selection cannot act to "weed" that individual out of the population. If that individual mates with another individual that has one normal copy and one recessive copy of the gene, they have a 1/4 chance of having a child with the disease. The same thing happens in plants, but many plants can be what we call tetraploid; this means they have four copies of each gene instead of only two. You can see how this might be of great advantage in the plant kingdom; in order to show the effects of a recessive gene, you would need to have four copies of the gene instead of just two, which would occur much less commonly.

The presence of a large number of red pine trees in an area is usually indicative of a widespread natural disaster of some kind, usually a forest fire. Because they are incredibly intolerant of shade, they are often the first trees to colonize an area after fire. Contrary to popular belief, this isn't because the seeds require intense heat to open (which is the case in some other coniferous species). When you intensely burn an area it rapidly decomposes the dense organic layer on top of the soil which allows for easier seed penetration, it burns off insects that might eat the seeds or young saplings, it removes the competitive ability of understory trees and shrubs by killing all (or some) of them, and thins out the branches of the trees that make up the canopy. Fires provide optimal growth conditions for the red pine and other primary colonizing species that are shade intolerant.

The uses of the red pine include lumber, pulp and paper, and for landscaping purposes.

The Angel Oak

Species name: Quercus virginiana

Common name: live oak, southern live oak

Location: South Carolina; photo #1 from HERE, photo #s 2-4 from HERE

Since today is Independence Day in the United States, I figured that, like for Canada Day, I would profile the national tree of the US for today's blog. Unfortunately, I don't have any other spectacular pictures of oak trees other than the ones I've already posted so I had to resort to the internet. I have heard of this rather iconic tree in Charleston, South Carolina and after seeing the photos of this tree I really want to go see it in person! It's called the Angel Oak, and (thankfully) it's a native species of oak to the southeastern US called the live oak or southern live oak (since the common name "live oak" applies to many species of oak in North America, South America and Europe). This species is also iconic to the southern United States, being the tree of choice to line roadways in Georgia, Louisiana, South Carolina, and Florida. It is an evergreen tree in most areas of its range (the further north the more likely the tree is to lose its leaves in the fall, and the further south the more likely the tree is to lose its leaves during the driest months in the summer) with dark green, glossy leaves that look nothing like what you would typically think of as an oak leaf. They have almost a smooth border with no lobes, and look very much like a leaflet of a willow tree; long and quite narrow. They do form the characteristic acorn of the Quercus genus, so that should give away that it's an oak at first glance.

The Angel Oak is a single tree that is estimated to be between 350 and 400 years old, so it was an adolescent (as far as "tree years" go) when the United States gained their independence from Great Britain in 1776. Despite providing shade for almost 17,000 square feet of parkland, it's only about 65 feet tall! One of the defining characteristics of the southern live oak is it's short stature compared to its outward growth (the longest limb of the Angel Oak is 105 feet long).

How this tree obtained its common name is up for debate, and which story you believe has more to do with folklore and if you believe in ghosts than anything else. It has been said that the oak is growing on the former Angel estate, but the borders of that estate land have been recently disputed, and the border of the estate may or may not include the tree. The other story behind the name is that the Angel family heavily employed slave labor on their farm and now the ghosts of the slaves gather around the tree. Regardless of how the tree got its name, it has become one of the most popular tourist attractions in Charleston. Not bad for a tree!

Happy Independence Day to all my American readers!

The railroad tree

Species name: Tsuga canadensis

Common name: Eastern hemlock

Location: Ontario

The Eastern Hemlock is a species of coniferous evergreen tree native to the east coast of North America (the Maritime provinces in Canada, and New England in the United States). This might seem obvious from its name, but I'll profile a plant in a later blog who's common name might sound like it's origins are in North America but they're really not. Most species of hemlock are native to Asia; there are only a few (3 out of the 9 or 10 species in the genus) that are native to North America, and only one native to Ontario (of the other two, one is native to the Carolinas in the United States, the other is native to the west coast of North America near Alaska and northern British Columbia).

Historically, the hemlock tree was very important in the lumber industry not for house building or furniture building materials, but for railway ties. Hemlocks are very slow growing trees, so it would take hundreds of years for a tree to be big enough to cut down to make one post. Trees were felled on the east coast, their bark cut off to make a square shaped log, and they were cut into pieces and shipped off to build the railways across North America. This was an incredibly destructive process, and there are still forests in the eastern half of Canada that have never recovered from this practice (the majority of which ended in the early 1900s when there were no more large Eastern hemlocks left). My PhD supervisor and I went out to a woodlot a couple of summers ago to look for mushrooms and it was one of the few remaining old growth forests that had once been dominated by hemlocks; there are still stumps left of enormous old trees that had been felled. The good thing about leaving all these stumps behind is that some really neat fungi grow on them!

Unfortunately, the Eastern hemlock is under severe threat of population destruction by an invasive pest from Asia (that usually attacks the Asian species of hemlock which are relatively resistant to the insect). The insect is called the hemlock wooly adelgid, and when it latches onto the tree it often gives it a blueish "furry" appearance at the base of the needles. The insects drink the sap from the tree and burrow under the bark, destroying the tree's ability to transport nutrients from the roots to the growing branches, or the photosynthesizing needles to the growing roots. This causes extreme plant stress, more often than not leading to death. The only way to get rid of these adelgids once they attack the tree is to cut the branches off, and any arborist will tell you that hemlocks are especially sensitive to pruning because they are so slow growing. Pruning the ends of branches is fine, but cutting entire branches off should only be done one or two per year to ensure tree survival, not half the tree. Since there is no real treatment for these insects once the infection has started, it can essentially be taken as the kiss of death for the tree, and it should be removed from the garden immediately to prevent the spread. The other aspect of plant removal that must be taken into account is that the tree can't just be mulched or composted! It should be removed from the area and burned to kill the insects and to prevent future infection.

Eastern White Pine: Ontario's provincial tree

Species name: Pinus strobus

Common name: Eastern White Pine, White Pine, Wheymouth Pine

Location: Ontario

The Eastern White Pine is a native evergreen tree to Eastern Canada (Newfoundland to Manitoba), and has now been naturalized in the mountains of Poland and Czech Republic (naturalized meaning it is not native, but not out-competing native species). These trees are incredibly important in Canadian industry for timber and in the pulp and paper industry. They are the provincial tree of Ontario, and the state tree of Maine and Michigan. In the photo are the male or staminate cones, which are the cones that produce pollen. The pinecones that fall off the tree in the fall and are often used for decorative purposes are the female or carpellate cones which eventually produce the seeds. Staminate cones are the reason for many pollen allergies in the spring. These staminate cones are even the state flower of Maine!

Eastern White Pine trees were historically very susceptible to a fungus called the White Pine Blister Rust, which was introduced from either Asia or Europe during the 19th century. By the early 20th century the mortality of White Pines in some areas was as high as 80%. The Blister Rust is a fungus that requires an alternate host to complete its life cycle (in this case Ribes, or Gooseberry or Wild Currant). In the mid- to late-20th century, it was suggested by the US Department of Forest Pathology that if Ribes plants were removed from surrounding forest with White Pine, the disease can be controlled. This method was actually incredibly effective, and now mortality of "natural" pines (not ornamental pines, but those occurring naturally in forests) is about 3%. Now in New England in the US it is actually illegal in some locations to plant wild currant or wild gooseberry plants.

In the forestry industry, White Pines have historically been used to make masts for boats and some were even marked with a blue arrow as reserved for the British Royal Navy. This was a practice of great controversy in the US, leading eventually (at least contributing to) to the American Revolution. There are now more than just North American White Pines that are used as lumber to make masts of ships, should they be made of wood at all (most are now metal). Instead of growing trees for masts, we now grow pine plantations for Christmas trees and other lumber/pulp/paper purposes (building materials, furniture, carving, etc.). The sap of the White Pine is purified to make turpentine.

Surprisingly enough, White Pine trees are also used for food and as medicine by some native North American people. Pine needles themselves contain about five times the amount of Vitamin C as lemons (the typical Vitamin C benchmark), and make a great "Vitamin C tea." The cambium of the tree (the fast-reproduicing cells that produce the wood and inner bark of the tree) is commonly eaten by the Algonquin people. It is a good source of a chemical called resveratrol which has been touted as the "new cure" for just about everything that affects humans from diabetes to cancer. It has shown some promise as a chemical that will significantly reduce blood sugar as a potential treatment and/or cure for diabetes, but only in extremely high doses. The only human trial that has shown this was sponsored by a drug company, so any results that come from it have to be taken with a grain of salt. Other medicinal uses of this tree: as an anti-microbial agent used to treat gangrene by the Chippewa, and using the residue of slowly burning branches and roots as a treatment for dandruff.

Spindly Black Spruce

Species name: Picea mariana (formerly Picea nigra)

Common name: Black spruce

Location: Nova Scotia

I took this photo in Kejimkujik National Park on the bog boardwalk leading out to the beach. It was a pretty typical maritime spring day: cool in the morning, warming up quickly and becoming incredibly foggy then the fog burning off by the mid-afternoon. This was one of those rare moments where you could see more than 10 feet in front of your face as a fog cloud was blown out of the way.

Black spruce is a typical plant of the boreal forest in Canada and Alaska. It's a native evergreen tree with a very typical shape: somewhat bushy at the bottom, becoming much narrower and more spindly towards the top. One of the most impressive characteristics of this plant towards the northern part of its range is that its a great indicator of predominant wind direction. Black spruce grows very slowly, and slower still when the wind is pushing against the tips of branches. The "wind side" of the tree has much shorter branches compared to the "sheltered side".

Black spruce is one of the many boreal species that require fire in order for their seeds to germinate in great numbers, and so for that reason this species is especially successful at recolonizing the boreal forest after a fire. Since forest fires are relatively common in this forest zone, stands of boreal forest that are dominated by black spruce are often trees of the same age (as opposed to typical successional forests where there are old and young trees of the same species in the same location). Within the boreal zone, it's an incredibly common tree and is at no risk of becoming a threatened or endangered speices.

Black spruce trees grow slowly and never attain a very large circumference despite the tree's age. For this reason they are not valuable lumber trees in the construction business. They are, however, a major source of pulp for the paper industry in Canada. As cultural importance, the black spruce is the provincial tree of Newfoundland and Labrador in Canada.

A cancer-fighting plant

Species name: Catharanthus roseus

Common name: Madagascar periwinkle, cape periwinkle, "Old Maid"

Location: Ontario

This species of ornamental plant is one of the most impressive plants we have in Canada, not just for its showy flower display that lasts all spring and summer (and, depending on weather, sometimes well into the fall). Native to Madagascar (this is one of the few instances where common names really do reflect origins!), this Madagascar periwinkle had been brought to North America as an ornamental plant by early European settlers (who likely stole it from Madagascar on one of their many "expeditions"). Fortunately for the plant and unfortunately for native wildflowers, it has really taken off and is now one of the most invasive plants in Southern Ontario. Granted, it is strikingly beautiful...but we've got our own native wildflowers that would be just as nice growing in your garden! Ironically, in its native habitat it is a threatened plant due to habitat destruction from land conversion (from forested areas to agriculture).

Madagascar periwinkle is a perennial plant, meaning it lives for many years and sets seed many times over its lifetime. It is also an evergreen, meaning it doesn't lose its leaves. Even in Canadian winters, if you dig under the snow the bright green leaves will still be firmly attached to the plant. It is incredibly efficient at growing a vast root network to seek out water, so when the rest of your plants start to wilt from drought this one will be unaffected.

There are many hundred cultivars of Madagascar periwinkle growing in gardens around the world. In my garden at home, we have the "Grape Cooler" variety which has been selected for cold tolerance (why it can survive even under a thick layer of snow) and a purple flower colour. Native varieties of this plant often have much lighter flowers, from pink to white, with a very dark centre to attract insects to the nectar tube. Another great example of how plants have evolved mechanisms to coerce animals to help them reproduce.

This plant is vitally important in Traditional Chinese Medicine, and is becoming more and more important in local Western medicine, too. The Chinese have been using this plant for centuries as a cure for diabetes, malaria, and Hodgkin's disease. I'm not sure if it's actually effective against either diabetes or malaria, but extracts from the leaves are currently used as one of the most popular Western drugs to treat and cure leukemia (and to some extent, to treat Hodgkin's disease). This can be contrasted against a featured plant in a previous blog, bloodroot (one of the most notorious plant-based fake cancer cures).

Vinblastine and vincristine, the two biologically active pharmaceutical chemicals in Madagascar periwinkle were discovered here at the University of Western Ontario (sorry, but I will never call it Western University!) in the 1950s. At the time, it was noted by Dr. Noble and Dr. Beer that when Madagascar periwinkle was made into a tea and consumed, it lowered the number of white blood cells in the body. Normally this would not be a good thing (which is why you shouldn't ever eat this plant, raw or cooked!), but if you have a disease that specifically attacks white blood cells it might be a good treatment or cure. It went into clinical trials, was demonstrated to be incredibly effective against lymphoma, leukemia and Hodgkin's, and the extracts were made into a commercially available drug (trade name was formerly Oncovin, I'm not sure what it's called now that it's out of patent). The two chemicals are no longer extracted from the plant, but rather synthesized in the lab since it's so much cheaper and more practical.

Sticks, sticks, sticks

Species name: Acer saccharum

Common name: Sugar maple

Location: Ontario

So this isn't your typical thoughts when it comes to a maple tree. And this probably isn't the kind of image you want to see when promised that spring is "right around the corner" (aren't we promised that every year at the end of March?!). But it's a fact of life that trees lose their leaves in the fall, overwinter as a bunch of upright sticks, then grow new leaves in the spring. But do all trees do that?

Unfortunately, nothing in Biology ever has a rule for which there are no exceptions. We can say that all trees lose their leaves then regrow them at some point in their life cycle, but that would be just plain false. An important concept to introduce is the difference between evergreen and deciduous trees. Evergreen trees are exactly what they sound like: always green. They never lose their green parts, and they're always biologically "active", even when it seems like all that they're doing is sitting there. In elementary school you learn that conifers are evergreens, and everything else loses their leaves. In reality, this is false. MOST conifers in Canada are evergreens, but there are some clear exceptions like Dawn Redwoods and Larch (and a few others, but those are extremely uncommon in Canada). Deciduous trees are those that lose their leaves in the fall to regrow them in the spring, and are often thought of as being the leafy plants. This is also not entirely true, since there are many tropical leafy trees that are considered evergreens since they never lose their leaves.

Another misconception is that the way the seasons work in Canada is the way they work everywhere. In reality, almost every country in the world has "seasons". Even tropical countries right on the equator that have no clear distinction between spring, summer, fall and winter still have a wet and dry season. In fact, we have the same thing in Canada: winter would be considered our "dry" season since the only form of precipitation (snow) is biologically unavailable to plants. The soil is also too cold to allow for water absorption, so the trees go dormant. Same thing in the tropics: during the dry season, many deciduous trees will lose their leaves and enter dormancy to regrow them during the wet season. There are some plants in the tropics that take this to an extreme, and any time there's a period of drought (anywhere from 7 to 14 days without rain, and it doesn't matter what time of year it is) the tree will shed its leaves and regrow them all after the next rain. A neat example of nutrient cycling in the tropics; nutrient recycling in temperate countries could never happen this quickly, and so if a tree shed its leaves any time it didn't get water for a prolonged period it would never be able to grow them back fast enough and would die.