The creeping vine from Virginia

Species name: Parthenocissus quinquefolia

Common name: Virginia creeper

Location: Western University campus

As promised in my last blog, this post is about the "other" common vine with blackish-blue berries common, and native, to this area: Virginia creeper. Many people are actually surprised to learn that this species is native, as we don't often associate native species as being potentially invasive species. Anyone who has ever grown Virginia creeper in their garden under ideal conditions knows it will absolutely explode in growth and smother out anything in its path; a rather unfortunate characteristic since I like to encourage gardening with native species! Fortunately, Virginia creeper isn't as vigorous as grower as periwinkle or kudzu, so when you go to bed one night and wake up the next morning your house won't be covered in it (that has never actually happened, but at times it sure feels like both of those plants could grow that fast). The Virginia creeper vine is native to eastern North America, and its native range extends from Quebec and Ontario south to Texas and Alabama. There's a bit of an argument about whether or not its native range is also extending into northeastern Mexico (a few botanists believe it to be either introduced or a different species, depending on who you ask).

Virginia creeper is one of the banes of my existence because it doesn't follow the rules set out by its Latin name. The species epithet "quinquefolia" refers to its five leaflets, all originating from the same point on the petiole which is referred to as a palmately compound leaf. Unfortunately, no one told the Virginia creeper that it had five leaflets originating from a common point on the petiole. When young, sometimes the leaves only produce three leaflets (called a trifolate leaf). This is all fine and dandy, except what other plant might you know about that produces three leaflets from a common point, with the same general leaflet shape as Virginia creeper, and can also grow as a smothering vine along tree trunks? That's right, poison ivy. If you don't want to get mistaken for poison ivy, don't go looking like poison ivy! Geez. There have been a few times I've been out in forests where I could have SWORN that what my supervisor was grabbing onto to push out of the way was poison ivy, but turns out he knew it was only an abnormal Virginia creeper vine. Better to be safe than sorry I think, so I steer clear. Based on the skin sensitivity I display towards other stinging or itchy things (plant or animal-based), I would probably blow up like a balloon if I got the two confused. Keep trifolate leaves away from me and I'm a happy camper :)

All of that being said, Virginia creeper can be a nasty plant in its own right. The whole plant contains oxalic acid, which can be a very potent skin irritant to some people (and those with sensitive skin to other plant-based toxins, especially rhubarb juice, are most likely to be affected). The berries also contain very high levels of oxalic acid and so should not be eaten. Rarely will they cause any type of major problem other than intense intestinal discomfort, but if children confuse them for grapes and eat a lot of them there could be severe consequences. The oxalic acid crystals are sharp enough to perforate mucous membranes, and so severe internal bleeding can result after ingesting significant amounts. As with many toxic plants, a hot-water infusion made from the fruits (most of the time, but sometimes also the leaves) of this plant were used by Native North Americans as a treatment for heart conditions, diarrhea, prostate disease (or other diseases or disorders that might cause difficulty or painful urination), and joint swelling due to (most often) rheumatoid arthritis. No clinical trials have ever been set up to determine if the plant can be effective against any of these conditions, but the possibility is there.

Aside from its traditional medicinal use, this plant is becoming more and more popular as a garden ornamental species. It is very successful in full sun, and does a great job of climbing up buildings to act as insulation from the sun (and so is especially successful on south-facing walls). Fortunately for homeowners using this plant in landscaping, it (like Boston Ivy but unlike English Ivy) produces sticky knobs to attach itself to a substrate (like your brick wall on your house). English Ivy, that nasty little vine, produces penetrating roots that worm their way right into the mortar between the bricks in order to anchor itself. This means that Virginia creeper is a much less destructive plant to grow on the side of your house. There's always a catch to all things that sound to good to be true, isn't there?! The catch for this plant is that removing adhesive knobs can still be quite a labour-intensive process because pulling the live plant from the wall will still rip out small pieces of brick and mortar along with the adhesive knobs. If, however, you cut the plant at the base (either at ground-level for complete removal or just a branch here and there for trimming purposes) and let the plant wither and die on the house, it can be removed once brown with no damage at all (the adhesive knobs have to be alive to be adhesive!). It's like magic! The only downside is that Virginia creeper vines do lose their leaves in the fall (but not before turning a BRILLIANT shade of red first), so you don't get the same kind of winter insulation as you do with English ivy. But for the cost of having to re-brick the side of your house...I think the substitution is worth it!

Wine? Wine not!

Species name: Vitis riparia

Common name: riverbank grape

Location: Western University campus

The riverbank grape is one of our great native vine species (the other major native eastern North American species to be featured in the next blog, Virginia creeper). It is a very vigorous grower, capable of growing up to the top of a riparian forest tree canopy (not nearly as tall as a "normal" tree canopy of a forest, since trees that live in riparian, or riverbank, areas don't tend to be able to grow as tall). In the southern areas of its native range it can be a real pest species, but here in Ontario other native species are pretty good at competing with it. Some trees have a harder time than others, but non-native species have an especially difficult time with the smothering tendencies this species sometimes has. That being said, as soon as it is transplanted, either naturally via bird poop (the most common animal vector) or "artificially" via human transplantation, into an area of lowland or upland forest the forest canopy can really suffer as a result. It is remarkably good at smothering new saplings before they have a chance to grow tall enough to escape it, and some forests are so thick with grape vines they're impassable. A great example of a species that grows well in harmony with other species in its native habitat, but can become a real pest, even in its native range, if introduced beyond those limits.

The riverbank grape has a bit of a bad rap in Ontario and the northeastern United States, but that perception seems to be changing a bit. In the 1940s and 1950s, the US government (the Canadian government quickly followed suit) decided that riverbank grape vines were a forest pest and that this species should be eradicated. There had been a lot of accidental introductions of this species into areas important in the logging and lumber trade, and if you're allowing a vine to smother your profits you're not a very good businessperson! So instead of just local eradication programs, these programs were carried out across the United States and into Ontario and Quebec, and whenever a riverbank grape vine was seen in a forest (either riparian area or otherwise) it was sprayed with very toxic herbicides. This was very effective at killing the vines, but also equally effective in killing all of the surrounding vegetation and poisoning the soil (both for soil microbes, very important in forest health, but also making it inhospitable to new seedlings). Unfortunately, it was far too late before anyone realized what was happening, so you still find "dead zones" where mature trees escaped the soil poisoning by having a root system vast enough to support itself with un-poisoned soil, but the understory species are completely missing. I have a rather personal connection to riverbank grape, because one of the species of fungi that I study for my PhD grows exclusively on grape vine in North America. Unfortunately, there's a catch (as there always seems to be with rules regarding where fungi are most likely to be found): it only grows on mature, living or dead grape vine. This means that any suitable habitat that might have been in forest ecosystems in the 1800s when a lot of the work was being done on the fungal flora of North America no longer exists for this species. For this reason, it was collected three times in the 1880s by great, now long-dead, mycologists only to never be recorded ever again. Have these species gone extinct because of our destruction of their host species? No one, including myself, knows that for sure. Since the 1930s there has been a lack of concerted effort to document the diversity of forest species, only re-invigorated in the early 2000s. What I can say is that for the last 6 years whenever I'm in a forest where there's grape vine I look for it...and haven't found it yet. Perhaps I'm not looking in the right spot, or perhaps it doesn't exist anymore. I'll let you know in 20 years when I either find it or give up looking. ;) This idea of "disappearing species" is not unique in mycology; there are also a lot of plant species that were discovered during the times of the Great World Explorers (as I like to call them) that have never been found again. Part of the problem stems from the lack of location data for the collections--how do I know where "Aunt Edna's House, near the south greenhouse but past the wood pile, 5 minutes from the beach" is?! Sure, maybe EVERYONE in 1872 knew where Aunt Edna's house was...but it's long gone by now. You don't realize just how useful GPS coordinates are until you have to figure out something like that!

Anyway, back on topic...

Riverbank grape fruits are reportedly edible, and were also reportedly an important food source in the summer for early settlers in North America. Now, I'm guessing that tastes have progressed a bit since those times, or perhaps they were much less picky eaters than we are now (or maybe a bit of both). Have you ever tried a grape from a wild grape vine? They are TERRIBLE. I wasn't expecting a sweet grape when I tried one, but holy jeez. This was...terrible. That's the only way I can describe it. It was gooey and had the most awful texture on the planet (almost like jello on the inside), plus one of the most sour fruits I've ever had in my life (puts the Cornelian cherry to shame, which you can read all about HERE, and I often eat lemons for fun...so that tells you something about my tolerance for "sour"). My friend Tanya convinced me to try one when we were out geocaching one afternoon, and I could taste the lingering "lip-puckering sour" in my mouth for hours. That's the last time I ever listen to Tanya. Ha.

Sure, the grapes don't taste that great and the plant isn't all that much to look at (although, I personally really love the shape of their leaves and the cute little curving tendrils that are most visible during the winter and early spring), riverbank grape is one of the single most important "novelty agriculture species" that we have in North America. I call them an agricultural novelty not because their use is new, but because the product we get from them is certainly not necessary for everyday life (some people might argue with me on that one; we'll agree to disagree) nor has it ever been. Wild grape vines are VERY tolerant to winter conditions in North America, which can be incredibly harsh, especially in the ground. Traditional wine grape vines, of the species Vitis vinifera, don't have a very cold hardy root system, and are prone to freezing damage in northern climates. For this reason, riverbank grape rootstock is often grafted onto a wine grape scion (or "top") for commercial grape production for the wine industry. Once grapevine producers were experts in the creation of natural hybrids, they started experimenting with different varieties of V. vinifera as well as V. riparia to make more cold-tolerant grape vines, but with the same commercial qualities of traditional wine grapes. Another major benefit is that the resulting hybrid is much more resistant to common fungal diseases encountered on grape vines. Eventually what was obtained were varieties that were genetically 50-80% wine grapes, and 20-50% riverbank grape. Baco Noir, Marchel Foch (sometimes called Marechal Foch) and Frontenac grapes are all hybrids between these two species, and produce some of the best wine in the world. Isn't it amazing what a little traditional plant breeding can do?! Cheers to grapes.

Traditional uses by Aboriginal North Americans are also numerous; they are used as a food (although, I'm guessing in small numbers), to make jellies and jams, and to produce a type of traditional North American wine. From what I understand, this wine is really unpleasant when compared to wine from a "real" winery, but it really packs a punch: it has 2-3 times the alcohol content of a traditional wine. Maybe it's alcoholic enough you don't realize how terrible it is! Not commercially sold, but every so often you might be able to find some courtesy of a backyard brewer. Let me know how it is, if you get a chance to try it.

A joy for travellers to see

Species name: Clematis x jacksonii

Common name: clematis, traveller's joy

Location: My house (London, Ontario)

Clematis plants are some of the most interesting plants to me because of their quirkiness and eccentricities. They don't follow the "aesthetic rules" that most flowering plants do, and that's definitely one of the things that makes them so cool. This species, a hybrid between two Asian species then hybridized again with a common garden species popular in the late 1700s in gardens in Europe (the history of this garden hybrid is unknown, but likely from Asian ancestors, too). Due to the fact that this plant is a hybrid it technically carries no weight according to the IUCN Red List of endangered and threatened species, but I can vouch for the fact that this plant is not likely to spread, nor is it likely to reproduce and escape from the garden. We moved into our house in March of 2006, and I've never witnessed this plant producing seeds (which are actually quite spectacular; they're like dandelions with a bad hair day). Not good if you're the plant, but great if you're the gardener that doesn't want to clean up after the plant!

The second image shows the twice-compound leaves, which branch twice into three. The leaves are produced oppositely on the stem (the purple arrow points to where the petiole, or the "leaf stalk", attaches to the stem and you can see that there's another leaf growing off the stem in the same place in the opposite direction), and each petiole divides into three at a single point (you can see the path the petiole takes in yellow). From there, the petiole divides into three again, and at the end of this division there are three leaflets (red arrows). Sometimes leaves can do some strange things and not obey the rules. Instead of producing a leaflet at the end of the petiole, sometimes the leaf turns into a modified structure for climbing: a tendril.

In general, there's a lot of misconceptions about "specialized" plant organs used to attach plants to houses or climb up support structures. Peas are well-known for their tendril producing abilities, and clematis vines should be, too. Clematis vines produce very little growth from their old stems; they much prefer just to send up new shoots from their rhizomes just under the surface of the soil. If you consider just how much this plant has grown in a single growing season, obviously the height of the vine would produce too much weight for the plant to handle on a skinny non-woody stem. To help hold it upright, tendrils are produced to wrap around support structures. These tendrils originate from the leaf, and if you cut straight through a tendril and make a very thin cross-section and look at it under the microscope you'd notice that a tendril has the structure of a rolled-up leaflet. Pretty neat! These tendrils have another secret ability: they respond to touch. Have you ever wondered why a tendril coils? It's not because one side is produced "smaller" than the other and so it spirals to compensate for the lack of space. It's actually the plant that senses a suitable object is touching the tendril and has been for long enough to provide support, and the tendril will start bending towards that object as it grows. If you're REALLY patient (and I mean you would give a saint a bad name with your level of patience) and have a lot of time on your hands, take a tendril that's grasping at something to curl against, and hold your finger against it for maybe 30-60 minutes. Try to move as little as possible, but a little movement is OK. After your hour is up, you can walk away and return to your clematis the next day. What happened to the tendril? I bet it will have super-coiled around itself and made a mass of curly tendrily mess. There was a signal that the plant received when your finger was against the tendril that said "SUPPORT!!! COIL QUICKLY!!!" and it responded--just too late to be useful. You've now manipulated a plant into reacting to your touch. Pretty cool! See, manipulating plants for your own amusement can be fun...

The flowers of this plant are also incredibly unusual. There are flowers that produce four petals, five petals, or six petals (the majority seem to produce five). If you think that all of the flowers just had six petals and some lost a few before I took pictures of them, I also managed to find one of each version that was just getting ready to open, so I can definitely exclude that as an explanation. Why does this happen? As far as I know there's no explanation. None. Completely stumped. Our clematis grows in the shade, so I thought perhaps it was just confused and suffering from a lack of sun (these plants definitely prefer full sun or at minimum partial sun to be most happy) but I just looked up pictures of the plant on Google Images and there are people growing theirs in full sun and noting the same phenomenon. Find an explanation for why this happens? Let me know! I've always been interested in learning about why this happens.

Other than their obvious ornamental value, some clematis species (there are over 300 of them) have been used in North America as medicinal plants for centuries. It was used to treat nervous diseases and migraine headaches, but don't get excited about the medicinal properties of the plant in your back yard. Most clematis species are highly toxic, and the sap that's exuded from cut stems is highly allergenic, is phototoxic (meaning it will cause extreme rash and burning when the sap on your skin is exposed to intense sunlight), and can cause internal bleeding if ingested. This plant is best used as an ornamental species and not a backyard medicine. It's also probably best to use gloves when pruning this plant; some people are more sensitive to the toxins in the sap than others, but always better to be safe than sorry. The phototoxic effect can last for years, despite washing the sap off your skin.

The noxious cow itch vine

Species name: Campsis radicans

Common name: cow itch vine, trumpet vine

Location: Ontario

The trumpet vine is native to the southeastern United States, reaching as far north as Kentucky. Despite this, it is incredibly cold-hardy, and can survive winter temperatures as cold as -30 degrees Celsius. For a subtropical species, that feat in itself is incredible. What's even more incredible is that it actually does better when transported to "strongly temperate" areas (locations that have a clear summer that is very warm, and a clear winter that is very cold) like New England and southwestern Ontario. There, the vine becomes incredibly invasive and can be very destructive. In fact, "radical pruning" is recommended in order to control its growth; it can grow up to 30 meters in one growing season!

This plant is one of the many vines that produce structures called tendrils that act almost like support beams that help keep the plant upright and attached to its substrate, whatever that might be. The plant that made tendrils famous is the garden pea plant, which has tendrils that react so quickly to touch you can almost watch them grow without a time lapse camera! The cow itch vine takes this to a whole new level. It can actually use its tendrils almost like hole borers, and can penetrate into mortar between bricks, and can split apart perfectly healthy trees. Nevermind what it can do to hydro or telephone poles! Outside its native range it truly is a menace, and should be avoided at all costs (despite its incredible beauty). The one good thing about this plant is its flowers; the bright red colour and the trumpet-like shape attracts every species of hummingbird to have ever come in contact with it, so if you'd like some great hummingbird viewings on warm winter days, go find some other poor gardener that planted this vine and camp out in their yard with a camera. The flowers are so prolific in nectar that the birds are very likely to "put on a show" for you while you just sit and snap pictures!