This clock won't tell time

Species name: Thunbergia grandifolia

Common name: clockvine

Location: Dominican Republic

One day my mom and I went on an excursion that drove all around the countryside and visited a traditional house and farm in the middle of nowhere (and what a beautiful middle of nowhere it was!). We got to walk all around the house and look at the gardens, and they led us through their "agricultural plot" behind the house that had a lot of traditional Dominican food growing. This was one of the plants that was being used as an ornamental species in one of the gardens of the home, and I bet it won't be long before they regret planting it. The clockvine is native to China, India, Nepal and Burma where it grows like a weed. It is capable of living happily in any tropical habitat, loves both very soggy soils and dry, arid soils, can tolerate full sun as well as full shade, and other plants in the garden are the least of its troubles. In some tropical areas of the world, like tropical Australia, it has taken "invasive weed" to a whole new level. It is nearly impossible to eradicate because of its successful growth from either seeds or underground rhizomes, and so it will likely destroy all of the native habitat is has grown into before snuffing itself out.

Since this vine is such a beautiful flowering vine, it's no surprise that it's popular around the world for its ornamental value. In fact, almost every species of the genus is prized for their flowers and very fast growth (as well as the ability to tolerate almost every environmental condition that is thrown at it; including light snow for some species!). Unfortunately, this means that this vine has become invasive on all continents, everywhere it has successfully grown. Something needs to be done to ban the sale of these plants!

There are also studies that are currently looking at what to do with these vines, since they're already in numerous locations around the world in gardens (where they are relatively easy to control as long as you have garden shears and some time on your hands) and have since escaped cultivation. There was the suggestion that these plants would make excellent biofuels since they grow so quickly and are so tolerant of environmental fluctuations, but I'm not sure if anything has been done about this suggestion. They are most definitely "sustainable" in the traditional sense, but at what price? Once we harvested all of the plants that are growing in wild areas, then what? Do we plant more of them and risk them escaping again? Using highly invasive species for biofuels (either fermenting parts of the plant to produce bioethanol or just burning the plants directly to produce energy) is a very fine line to walk between rehabilitating an ecosystem and encouraging its complete destruction.

Botanical Chinese Lanterns

Species name: Abutilon megapotamicum

Common name: trailing abutilon, Chinese lanterns

Location: UWO Greenhouse

When I first saw this plant (unlabelled in the greenhouse) I thought "what a neat plant! They look like little Chinese lanterns. I'm going to call this the Chinese lantern plant!" Turns out I'm just as good at naming plants with common names as those who have come before me decades (even centuries) before; one of the common names of this plant is indeed the Chinese lantern plant! Contrary to what you might think from the name, it is not native to China, or anywhere in Asia for that matter. It is native to South America, in the tropical forests of Brazil, Uruguay and Argentina. I'm not sure of the status of this species in its native range, but if it's going through what every other plant native to the Amazon is going through it will be at risk of becoming threatened if the rate of deforestation doesn't drastically decrease.

The way that this plant flowers is completely backwards from what you would guess based on the images, and completely backwards from what I thought in my mind. I thought that I could blog about how the fruit of this species was especially cool because they have paper-thin walls, and the walls of the fruit either are shaken open in the wind when the fruit is mature or they are auto-digested in order to release the seeds. In fact, that red fruit-like structure is the immature flower before it has opened up. Those red "fruit walls" are actually sepals, the bract-like structures that cover the developing flower in order to protect it. What I thought was the spent flower, the picture at the bottom, that was turning into the fruit is actually the flower growing out of the protecting bracts and eventually it will unfurl and be a bright yellow-orange. The plant sure stumped me! I was thinking it was very closely related to the bladder cherry (also called the Chinese lantern plant), but they're not at all related and not used at all for the same reasons. The bladder cherry is sometimes used as an edible plant, but I've only ever heard of it being used as a decorative plant. In fact, one of the uses my supervisor told me about the lantern plant I'm sure you can do with this one, too: literally turn them into lanterns. During the summer when these are ready to bloom, go out and catch lightning bugs (or fireflies; whatever you called them when you were a kid!). Gently squeeze the sides of the red sepals until they start to split open at the bottom. Stuff some lightning bugs in, and voila! Glowing botanical lanterns. Just remember to let the bugs back out after you've taken some photos.

In Congo, parrots are flowers

Species name: Impatiens niamniamensis

Common name: parrot plant, congo cockatoo

Location: UWO Greenhouse

The parrot plant, as its other common name may suggest, is native to Central Africa in the very small remains of what used to be a vast tropical rainforest. There haven't been any biodiversity studies recently that examine this species, but due to the rate of deforestation and the spreading drought in the area, I can imagine this species is probably at risk in its native range. Fortunately, this plant is readily propagated in the greenhouse so if rehabilitation studies were ever performed there is a genetic bank from which to select plants to recolonize the area. Due to its seed dispersal mechanism it may become invasive in some areas.

Like in the touch-me-nots (which are in the same genus; you can read all about them HERE), the seed pods of this species are like little seed grenades. When mature, even the lightest touch will cause the seed pods to explode and seeds go flying in all directions. An excellent dispersal mechanism, especially because these plants thrive in tropical climates. Here, the soil very quickly loses its organic nutrients in the top layers of soil and so plants need to disperse great distances from the mother plant in order to be able to successfully root and grow in the soil. Most greenhouses that propagate and sell the parrot plant don't even bother collecting the seeds, since the plant is so easily propagated from cuttings. When you do a cutting of a plant, usually you need to dip the exposed cut into a rooting compound which is full of plant hormones that signal the maturation of root cells from the plant's stem cells (in plants we call these meristematic cells). The plants are then placed in a soil substitute that is very porous, allowing for easy extraction of the plant from the medium to be planted in soil once the roots start to develop. This plant is even easier than that: cut a small piece off the end of a stem, put it in a cup of water and wait a few days. Sometimes it also helps to place a clear plastic bag upside down over the plant; this causes the environment around the plant to be very humid and warm, but air can very easily enter and exit through the bottom of the bag. After a few days, you'll start to see small roots form at the bottom of the stem. Put the stem in some soil, and there you go. A new plant! This is the way that one of my former students gave me my parrot plant about 4 years ago. I still have it, and while sometimes it just looks like a stick in the ground, it produces a new flush of flowers a couple of times a year. I have yet to see one of the fruit grenades produced, though.

The flowers of this plant are very well protected from predation, while at the same time attracting all different kinds of pollinators. Butterflies, bees and hummingbirds will be attracted to the flowers which produce a huge amount of nectar, as well as insects that have the ability to chew through the walls of the flower; since it's difficult for them to reach the bottom of the flower via the opening, they just bite through the outside and get their nectar reward by cheating. The protection of the flowers doesn't actually come from the flowers themselves, but from the stem of the plant while the flowers are developing. The plant produces large amounts of oxalic acid that are stored in crystals on specialized hairs on the stem right above the developing flowers. If a herbivore tries to come along and chew off one of the flowers, they will be instead rewarded with a mouthful of calcium oxalate crystals that will completely destroy their digestive system. Cats and dogs seem to have some sort of ability to sense this toxin produced by plants; I've never heard of a cat trying to eat through rhubarb leaves which have the same oxalic acid. Small children aren't so smart! It won't greatly harm a small child, but it will destroy your sense of taste for a good couple of days, as well as potentially making your mouth bleed quite a bit so parents of small children beware. The flowers of this plant can be interpreted as candy by small children so this plant shouldn't be within arms' reach.

It's not Christmas, but here's a Cactus!

Species name: Schlumbergera truncata

Common name: Christmas cactus

Location: UWO Greenhouse

I was pondering saving this blog for sometime around Christmas next year, but when I saw how the last picture turned out I wanted to brag about it right away. Doesn't it look like it's illuminated from the inside?! One of my proudest moments, and I have no idea how to re-create it. :)

This species of Christmas cactus (there is more than one, and most of the Christmas cacti sold in store around Christmas are actually hybrids) is native to a very small area in Brazil, in the Amazon jungle near Rio de Janeiro. It was once severely over-harvested in the wild due to the ornamental plant trade, and so European species of the same genus were purposely introduced into the wild to prevent over-harvesting of the native species. Since then, quite a bit of hybridization has occurred between the two species (both in the wild and in greenhouses), and so most that are sold in stores are not a "true" species. The Christmas cactus is an epiphyte, living on standing tree trunks or off of tree branches. It also has the ability to grow on the surface of rocks in very humid areas, this is called an epilythic plant. There are a few plants I've already blogged about that are also notorious lithophytes: the monkey pitcher plant (read about it HERE), paph orchids (read about them HERE), staghorn ferns (read about them HERE or HERE), and other more "regular" species of ferns (read about one HERE). There are also very close relatives of the pineapple that grow on rock faces in the tropics, and can even grow (and commonly do) on telephone and electrical wires!

There are very few pests of Christmas cactuses, but they can suffer from all of the same diseases and pests that any greenhouse plant can (aphids, mealybugs, and Fusarium vascular wilt; all very common in greenhouses). It does have a unique disease: Christmas Cactus X virus. Like with the Hosta X virus, there is no known solution to infection once it is visible in the plant, and so it is strongly suggested that plants be destroyed once symptoms are noticed (usually a yellowing around the vascular system of the plant, the "veins", and the infection can jump from section to section in the stem).

Tropical pitcher plants

Species name: Nepenthes sp. (a hybrid)

Common name: pitcher plant, monkey cup

Location: UWO Greenhouse

This species of pitcher plant is tropical in origin from somewhere in the Old World Tropics (the complete range of all of the species of Nepenthes is included at the bottom of the blog post courtesy of Wikipedia). The label on the plant says it's a hybrid Nepenthes, but the label corresponds to a hybrid that looks nothing like the pot hanging in the greenhouse. Perhaps the pictures on the internet are wrong...there aren't many of them. For now it's probably just safe to say it's a hybrid and leave it at that. Nepenthes species (there's about 140 of them worldwide) are almost all threatened, endangered or critically endangered. There are only a small handful that the IUCN and CITES consider of "least concern," but there are also quite a few that are considered "data deficient." For those of you considering going to graduate school, here's a project idea: catalogue the pitcher plants in Borneo and Sumatra, and come up with a monitoring program that involves going back into the bush and re-counting populations every year to judge reproductive abilities of a single plant and of a colony, plus motion-sensor video monitoring of the traps for what they're catching and what's consuming or destroying the plants. Mix that with cataloguing indigenous knowledge of the pitcher plants and what they're used for, and you've got yourself a PhD! I wish I had of thought of it sooner...sounds like an awesome time.

I profiled a native Canadian species of pitcher plant a while back (for a refresher, you can read all about it HERE), and if you remember what that species looked like you can see that the pitcher traps or pitfall traps are very different than what grows from Nepenthes plants. First of all, Sarracenia traps grow on the ground with the rest of the plant in boggy, swampy areas while Nepenthes grow in rocky, mountainous areas and the traps hang off of the leaves. The traps of the North American pitcher plant have curled lips that funnel rainwater into the trap (and is also very slippery to funnel bugs in, too), while the Asian species have a lid to prevent rain water from overflowing the trap and shelters the traps from falling debris. And the best part? The two groups aren't related to each other at all! The pitfall trap has evolved at least two separate times over evolutionary history, each time converging on what, today, looks like a nearly identical structure. The functions are identical as well; both groups have traps to catch insects to digest, but also act as vital breeding habitats for insects with aquatic larvae like mosquitos.

One of the biggest differences between the two groups, and the main characteristic that should lead you to believe that the two groups aren't related, is how the traps are formed. In Sarracenia, the traps are basically the leaves. The traps start to grow out of the rosette stem (a stem that is very reduced in size, and never reaching very high above the surface of the ground; the leaves and other plant organs radiate out from this point like the petals of a rose) as photosynthetic organs, and start to produce digestive liquid on the inside once mature. If the plant is going to produce normal leaves, they are completely separate structures that grow out of the rosette at the base of the plant. In Nepenthes, the traps actually grow off of the already-existing leaves. The leaf grows out of the stem rosette, photosynthesizes for a while, the starts to grow this long projection from the tip of the leaf. This projection continues to grow for up to 2 meters, eventually developing into a trap at the tip. Once the liquid inside the trap has been consumed by digested prey and the plant has absorbed all of the released nutrients, the trap and the entire leaf dies and falls off (very similar to the way that a Venus fly trap operates).

If you would like to start a Nepenthes collection in a greenhouse or in your home, it's entirely possible. There are enormous collections of these species in greenhouses around the world, and new cultivars and hybrids are being created every few years. The trick is how the plants were obtained. Collecting seeds and propagating the plants from seeds is illegal according to international biodiversity laws. If you are caught doing that, or caught with plants propagated this way, you may go to jail. This probably wouldn't be good, so make sure you know where your plants are coming from. The good thing is that the leaves readily regrow plantlets in tissue culture when exposed to the right hormone concoction (many plants are grown in tissue culture; tobacco being the most common). This means that only a tiny portion of a leaf is needed to grow the first plant (less than a square centimetre), and all other plants can be made from this parent plant. The downside is that all plants are clones, but if you're just growing it inside it doesn't matter much. If you're growing them to replant in the wild, this would be an enormous problem because of pathogen threats to genetically uniform populations. Make sure you ask your source of Nepenthes how they were grown and where they were collected from! If the person doesn't know, don't buy it.

The native habitat distribution of species of Nepenthes (courtesy of Wikipedia)

Stop touching me!

Species name: Mimosa pudica

Common name: sensitive plant

Location: UWO Greenhouse

The sensitive plant is native to Central and South America, where it is so common you might mistake it for grass in some areas if you're not paying attention. It has been introduced to other continents around the world, and it has become invasive in Australia, South Africa, Tanzania, and many islands in the South Pacific (along with other continental countries in Asia). It has also been introduced to many countries other than just South Africa and Tanzania in Africa, but it does not seem to become invasive there. When I was in Panama, the hotel I was staying at looked out over the Chagres River (the main river feeding the Panama Canal), and between the hotel and the river was a big flood-plain covered in what I thought was grass. I went and took a walk one day and you could literally see where I had wandered around, since all of the leaves were closing behind me as I walked. It was a neat experience!

The sensitive plant is called the sensitive plant for a reason; it is sensitive to light, temperature, electrical charge, and touch. It is not just a common garden plant in some areas for these reasons; it has become one of the most widely sold tropical indoor plant species in recent years. When touched, the leaves of the plant very quickly close; the difference in time between the photo with the leaflets fully open and them fully closed was only a few seconds. After a couple of minutes the leaves open back up again. This is accomplished through the rapid movement of water out (in the case of the leaflets closing) or in (in the case of the leaflets opening again) to the plant cells. The plants, like animals for generating never impulses which result in movement of muscles, have the ability to rapidly pump potassium ions into the the spaces between cells, causing a change in osmolarity of the cells. Normally the osmolarity of the cell is slightly higher than the osmolarity of the space outside the cells; this ensures water is constantly being diffused into the cell, keeping it turgid (which would result in crisp lettuce instead of floppy, gross lettuce). When potassium is pumped into the spaces between cells, water moves across the cell membrane and the cell wall into the intercellular spaces to try to equalize the osmotic pressure. This causes water to escape rapidly from the cells, the cells collapse, and the leaflets close. Once the potassium is gradually cleared away from the intercellular spaces, the water is free to diffuse back into the cells, and the leaflets gradually open back up again.

Being able to open and close your leaves is a great response to have, but only if you can use it properly and with purpose. Pumping potassium into a space that usually has very little takes quite a bit of energy, and using all this energy for no reason probably isn't smart if you want to survive. So what would possess a plant to close its leaves in response to touch? What would the point of that be? Well, you can see some clues in the bottom photograph. The varieties of plants grown in greenhouses for sale as tropical indoor plants have been bred to have lost their spines. Wild varieties of the sensitive plant have tiny spines all along the underside of their leaves, and all along the petiole of the leaf. When the leaflets close, they expose these spines to whatever has cause the leaf closure, and this is hopefully an effective defence for the plant. Normally this works well; the sensitive plant has become so abundant in pastures because cows refuse to eat it (the spines mixed with the fact that it is mildly irritating to the gastrointestinal system of cows, sheep, horses and pigs) and insects stay away from it. When I was walking through the Mimosa field, I was happy I was wearing shoes! My toes would have been very unhappy if I wasn't.

The sensitive plant was once planted on purpose in areas of Africa, Asia and Australia (and the reason why it has become so invasive). Because it is part of the bean or legume family, it has nitrogen-fixing bacteria nodules along its roots. These nodules, containing the bacterium Rhizobium, convert atmospheric nitrogen (a form of nitrogen plants cannot use) into a biologically-active form of nitrogen. This is great for agriculture soils, since traditional crops like corn, wheat and rice all deplete the soil of nitrogen very quickly. If you can rotate your crops with a legume, you can put the nitrogen back into the soil for the next growing season. When the plant has the ability to escape and grow in the wild on their own, and has no known herbivores that will target it, it becomes dangerous to the environment. Eradication programs are now in place in Australia, where the sensitive plant has become especially problematic.

The toxin in the leaves of this plant, called mimosine (an alkaloid), is toxic to a few species of insects and so has been looked at in recent years as a natural insecticide. I'm not sure where the research stands on this, but it is produced in such small quantities in the plant that a method of synthesizing mimosine in the lab would have to be accomplished before it had any real industrial applications. Extracts from the leaves containing mimosine have also been shown to be a natural anti-venom to the deadly toxic monocled cobra snake, and so there may also be a medicinal application for this plant.

The Brazilian jasmine native to Brazil, not the Chilean jasmine native to Argentina

Species name: Mandevilla sanderi

Common name: Brazilian jasmine

Location: UWO Greenhouse

Brazilian jasmine is native to (you guessed it) Brazil, and until recently was considered part of a separate genus from the rest of the Mandevilla species in the genus Dipladenia. Most of the species currently classified in Mandevilla are native to Ecuador; this is one of the only species that's not. It's also one of the only species in the genus that's not critically endangered. It is still relatively common in the Brazilian rain forest, although the forest itself is decreasing in area by about 5-10% per year, so it will also soon be at risk. The common name of this plant is sometimes Chilean jasmine, but that common name actually refers to another plant, native to Argentina (yet another reason why common names of plants bother me...)

One of the characteristics of this plant that make it so attractive to gardeners (especially those with an indoor green thumb) are the strongly scented flowers. When in the appropriate location (in full to partial sun), these vines can reach heights up to 10 meters tall if given a support system in one growing season. If you want to encourage bushier growth, pruning the plant back almost to ground level every fall to encourage new growth in the spring would be best. The flowers can be tricked into being produced repeatedly during the growing season if the old flowers are pinched off (also called dead-heading). When grown in a container (either indoors or outdoors), it will rarely reach a height taller than a couple of meters.

There are no reports of this plant being toxic, but also none of it being edible. It is sometimes used in the perfume industry because of its scent, but doesn't have any other value aside from an ornamental plant. In the garden it will attract hummingbirds and butterflies because of the shape and colour of the flowers (and also a few bees...!).

The flowers of the Earl Stanhope

Species name: Stanhopea sp.

Common name: Stan orchid

Location: UWO Greenhouse

All of the plants in a greenhouse typically are labelled with species name, family that the plant belongs to, and the common name (sometimes this is omitted). In greenhouses where plants are actively being propagated, sometimes all of the pots are put together that are the same species, and the "master plant," or the mature plant from which all the propagules were generated, is the only one that's labelled. Normally this doesn't pose a problem...until species are so similar they're indistinguishable. The hanging pot this plant was in wasn't labelled, but one a little further down was (but that one didn't have flowers). After looking up that species online, the flowers are completely different between the pot that had the label and the one that had the flowers, leading me to believe the species is different. On the bright side, it's in the right genus!

Most of the 60 (or so) species of Stan orchids are native to Central and South America, and a good number of them are at risk or threatened due to their very narrow native ranges, and the deforestation occurring through much of Central and South America. Some of them, like Stanhopea wardii, are still very common and are also popular ornamental species (that come in multiple varieties with different coloured or patterned flowers). Many of the species with this genus don't exactly smell pleasant, but they don't smell gross, either. A great deal of Stan orchids produce an odor to attract very specific pollinators. The odor produced mimics the sex pheromones of the insects, so instead of coming to the flower thinking there is nectar to drink they come to try to copulate with it. It might be mean of the flower to coerce an insect into thinking it's a member of the same species, but effective for the flower in pollination. A neat mechanism, and one that is repeated across many orchid species (and other flowering species of plants in general).

The Stanhopea genus is named after the first Earl Stanhope (James), the principal minister to King George I in England. The title of Lord Stanhope is passed down through the first-born son. Many of Lord Stanhope's children are also prominent figures in history (many of whom were politicians, but one was very important during the French Revolution), so having a plant named after all of them is probably fitting.

Probably not the chenille you want to knit with

Species name: Acalypha hispida

Common name: chenille plant

Location: UWO Greenhouse

The chenille plant, also called the Philippines Medusa and the fox tail, is native to a set of small islands off the coast of Australia, between Australia and Indonesia. It has now been domesticated throughout much of the world with a warm climate year-round (it is not frost-tolerant) such as the southern United States, Mexico, Brazil, and Belize. It is still common throughout all of its native range, and much of its naturalized range.

The chenille plant can almost be considered a domesticated plant in some areas. It no longer does well in the wild in some spots it has been introduced because we (as humans) have subjected it to artificial selection to favour traits we like. The inflorescences, while usually having quite a bit of "fur" on them, were much shorter and much less hairy in the wild ancestors than the ornamental varieties sold today. This is considered artificial selection as this would never have happened naturally in the wild; increasing the hairiness of the inflorescences actually decreases the plant's ability to disperse their seeds. Not a good thing if you're the plant! There are also some cultivars of ornamental plants that have orange and even yellow inflorescences as opposed to the "natural" red colour (but this has also been artificially selected for increased intensity).

The family that this plant belongs to is called the Euphorbiaceae, or the spurge family (sometimes the euphorb family). The easiest way to determine if a plant belongs to this family is if it produces a milky white latex from the leaves when they are broken (which you can see dried on the leaf's surface in the third photo). If so, chances are much higher it belongs to this family than not. If you have sensitive skin like I do, you'll also probably find out the hard way that euphorb latex is extremely irritating to sensitive skin, completely separate of whether or not you have a traditional latex allergy. This should probably suggest to you that perhaps this plant shouldn't be consumed if it has the ability to burn your skin on contact, and you would be correct. The chenille plant is deadly toxic to small animals, and would make any human that tried to eat it very sick. If you have cats, you might want to reconsider before buying this plant (either to plant outside or as an indoor plant); my cat would mistake the inflorescences for cat toys in a heartbeat and it would likely be a deadly mistake.

Whether a prawn or a shrimp, this kind isn't edible

Species name: Justicia brandegeeana

Common name: shrimp plant

Location: UWO Greenhouse

The shrimp plant, a pretty fitting name if you have bad eyesight and a good imagination (don't look much like a shrimp otherwise...), is native to Mexico and was introduced to Florida where it has become naturalized. The pinkish "petals" around the bottom of the flowers start off white, turning pink as they mature. The darker, more intense the colour the more light they were exposed to during maturation. These bracts continue to grow along the top of the inflorescence stalk until they become too much weight for the plant to bear and they break off. The more mature the plant, the longer the bracts can be; in some fully-mature plants they can be up to a foot long! Thats a big shrimp. The leaves also change colour in response to light; the chlorophyll is easily bleached out in high light levels. As the leaves are exposed to more and more direct sunlight, white spots start to appear on the leaves. To get rid of the spots, shade the plant. If you like the spots (it doesn't seem to hurt the plant much, although there will be an upper limit for the plant's tolerance), make sure it gets lots of sun during the day!

The shrimp plant is incredibly sensitive for frost; it would do very poorly in temperate climates if left outdoors during the winter (anything below 7 degrees Celsius and the plant will die) but they do perfectly well indoors. Outdoors during the summer they will attract butterflies and hummingbirds due to the long, trumpet-like shape of the flowers and the abundance of nectar that they produce. They will also attract a lot of ants and bees, so probably best to make sure it's not planted right beside the doorway to the house. You might regret your decision...

Another common name of the plant is the "false hop" plant, named after the bracts in some cultivars that are yellow or yellow-green. They mimic the bracts of the hops plant which are used to give the characteristic flavour to beer, but just to warn the home-brewers amongst you: the shrimp plant won't make your home-brew taste like beer, or even like shrimp. There aren't any reports of the plant being poisonous, but it's certainly not edible, either.