When a flower isn't a flower: part 1

Species name: Bougainvillea spectabilis

Common name: bougainvillea, Napoleon, veranera, trinitaria (amongst others)

Location: Dominican Republic

Bougainvilleas are some of the most well known and well recognized tropical plants in the world. They originated from a relatively small band of South America, extending from Brazil west to Peru and south to Chile and Argentina. Depending on who you ask, there are between 4 and 18 species in the group (18 species is probably an over-estimation due to morphological variation displayed even in a single group of individuals, but I doubt there are only four species since diversity of plants in the tropics is so high). DNA sequence analysis definitely needs to be performed on this group to help not only with defining diversity, but also establishing if any of these populations (however isolated) are their own species and hence are in dire need of protection and conservation. One of the reasons why this is such a popular "resort plant" in tropical countries is because of its extreme ability to tolerate salt (it can tolerate being watered with seawater! That's salty!) it makes for an ideal ornamental species where salt spray (and periodic flooding due to storm surges) is common.

The "flowers" of the bougainvillea plant are great examples of how plants can entice animals into believing that they produce these large, showy flowers, but in reality produce small, barely noticeable flowers and fruit. The pink "petals" that many people believe to be the flowers aren't at all; they're just modified leaves containing pink pigments instead of green ones that act to attract pollinators (we call these bracts). The flowers themselves are the small white bits on the inside; there are usually three white flowers surrounded by three to six bracts. The bracts can be white, yellow, orange, red, pink, purple, green, or any colour inbetween. The only colour of bougainvillea bract that I don't think exists is blue; feel free to correct me if you've ever seen a blue one! There are over 300 different varieties of bougainvillea sold as ornamental plants, so it wouldn't surprise me if it had been "invented". Not only have there been hundreds of cultivars and varieties created through selective breeding, but bougainvilleas also naturally hybridize in the wild. There is even a population of plants in Peru, once thought to be a distinct species, that is a hybrid of two commonly found species. What's unusual about this hybrid population isn't the fact that it's a population of hybrid plants, it's where the parental plants are located. And that's nowhere near this hybrid population. There's no documented evidence, either, that either of the parent plants of this hybrid ever existed in this area of Peru. So how did they get there? Is this evidence of "early gardening" by native Peruvians? Is this evidence for population reduction in both parental species of bougainvillea? Can the seeds really be carried that far? Is there an animal vector (or was there an animal vector) that eats the fruit to disperse the seeds that we don't know about? Some fascinating questions with (so far) no conclusive answers.

Other than the ornamental value, this plant has no other uses to humans. The sap of the plant to some people is highly irritating to the skin; in people who are highly sensitive to the sap the reaction can be as extreme as it is to poison ivy. Other people either don't react at all or react with a slight rash and a mild itching. Luckily, unlike with poison ivy, a cut portion of the stem must come in prolonged contact with the skin in order to cause a reaction. This means that you should only be worried if you have been given the task of pruning a patch of bougainvilleas; if you have, make sure you wear a long-sleeved shirt and gloves and you'll be fine. This is also a very popular plant to turn into a bonsai (although, a different species is often used; B. glabra). The bougainvillea is the national plant of Guam, as well as the regional flowers of regions in China, Japan, Taiwan, Malaysia, Philippines, and the United States.

Stay tuned for part 2 of "When a flower isn't a flower" tomorrow, featuring one of the most commonly purchased plants for ornamental, indoor use.

(one of) The real jade plant(s)

Species name: Crassula ovata (formerly Crassula argentea)

Common name: jade plant

Location: UWO Greenhouse

This plant is a wonderful example of taxonomy and taxonomic rules. A few days ago I profiled the trumpet jade, which is a variety of the jade plant selected for its morphologically messed-up leaves (you can read all about it HERE). It is native to South Africa, and has (to my knowledge) never been evaluated for its species status. It is likely very secure (meaning there are many individuals left in the wild that readily reproduce), but since I've never been to South Africa I'm definitely not one to comment first-hand.

Historically, the jade plant was divided into two different species based on flowers; the pink-flowered plants were placed in Crassula ovata and the white-flowered plants belonged in Crassula argentea. There is also a correlation between colours of flowers and the general shape of the leaves; the leaves of the pink-flowered plants often have longer and more oval leaves, while the white-flowered plants have shorter, slightly rounder leaves. Unfortunately, this was just smoke and mirrors and a great example of how plants confuse botanists. The "rules" that were made up for how to tell C. ovata from C. argentea were 100% artificial, and it turns out they're both the same species. The colour of the flower is controlled by a single gene and there can be gene copies for white flowers or pink flowers. Depending on whether the plant has white genes or pink genes, the flowers can be more white, more pink, or somewhere in between. Leaf shape is probably more controlled by level of maturation and environmental conditions than anything else; leaves produced in very dry conditions and high amounts of sunlight will be smaller and more ovate than ones produced when lots of water is available and the temperature is cooler.

So once a species has two names, what do we do? In the naming of any kind of biological organism, there is a rule called the "Rule of Priority". Whatever name was validly published and applied to the organism first is the name that stays. There are some ways to make exceptions to this rule (especially in animals...zoologists are terrible with following rules of taxonomy!), but I won't get into that. If I don't get to bend the rules with my thesis when I'm naming species, no one else should :)

This jade plant has been masterfully cared for. How do I know this? Look at all the flowers! I've seen the odd flower or inflorescence group on a jade plant before, but nothing like this. One thing that you often have to be careful of when it comes to flowering plants (and some non-flowering plants that are gymnosperms) is that when they "moult" because their health is suffering, it's often mistaken for a sign of great health and prosperity. Some trees are known to do this: the tree somehow knows that it is infected with some kind of disease (insect, fungal, bacterial or viral), produces significantly more seeds than it would under normal conditions, then dies pretty quickly after the big seed flush. Oak trees also do this on an incredibly predictable cycle, which is off-set with population booms of squirrels. When the squirrel population is high, the oak trees need to produce an over-abundance of acorns just to keep up. They moult and over-produce acorns in an effort to overwhelm the squirrels and hopefully reproduce instead of being completely eaten. The results of this effort can sound like it's literally raining acorns. This effort seems to be incredibly successful, since most species of oak aren't at risk of becoming endangered due to squirrel predation any time soon. The moulting of oak trees depends on the species; red oaks are on a 4-5 year cycle and white oaks a 5-7 year cycle. Is this jade plant at risk of keeling over after this flush of flowers? I'm guessing not, but I'm really not sure. If it's mysteriously absent from the greenhouse in 8-12 months, then I think I know why! If it's still there, then its just a well-loved jade plant.

Dr. Seuss' jade plant

Species name: Crassula ovata "Monstruosa"

Common name: trumpet jade, Gollum's fingers

Location: UWO Greenhouse

The jade plant, and many of its closest relatives like this one, is native to South Africa. This specific cultivar, originally thought to be a hybrid of two different species but now known to just be selective breeding with the "true" jade plant, is rumoured on gardening websites to be incredibly rare, yet everyone seems to have one. I personally had never seen this plant until I photographed it in the greenhouse, so there might be something to this "rare-ness." I even had to call it the "Dr. Seuss Jade Plant" in my notes since I had never seen anything like it! Now that I know I can master the art of growing a regular jade plant, I'm thinking of asking the director of the greenhouses to make me a cutting so I can have one of these, too. The fun you can have with succulents! The status of the jade plant and its closest relatives is unknown in South Africa. I can't imagine it's in danger of over-hunting by greenhouses and gardening shops since it is so easily propagated, but it would have its own set of natural threats like infringing on its native growth range by urban expansion and conversion of arid locations into agricultural land. Is anyone from South Africa and can comment on how common it is in the wild? Or has ever been to South Africa and has noticed it growing there?

The jade plant is one of the most common indoor potted plants (both the bonsai version and the regular "full grown" version) because of their ease of growth indoors. When I was in high school and someone told me this, I would have called them a liar since I managed to kill mine in a few short months. Turns out I killed it with kindness (this was before I recognized that plants with thick, glossy, fleshy leaves are probably succulents and so dislike being watered more often than once every couple of weeks). Jade plants thrive under conditions of neglect, perfect for those of you with black thumbs that want to try growing plants again. The same cannot be said about getting jade plants to flower; they are notoriously difficult flower-ers in pots indoors. The key is to deprive them of water in October, expose them to cool (but not cold) nights, and no more than 8 hours of daylight for October, November and December. Resume regular care in January, and by February or March the plants will be ready to flower. This sounds like a whole lot of work to me for some puny little white or slightly pink flowers; plus, the leaves are so attractive on their own!

Along with over-watering, there are a few indoor pests that are more than happy to attack your jade plants should they find their way into your home. The first are mealy bugs. They're easily removed with a toothbrush (don't press too hard! You want to scrape them off the cuticle or the waxy coating of the leaf, not scrape into the cuticle and damage the epidermis; this will lead to far more problems later on), and then the whole plant can be sprayed with a very mild dish soap solution in a spray-bottle. Make sure you cover the soil with a towel because even a slight amount of soap in the soil can damage the roots and hence the whole plant. The second problem are spider mites which can spin a white, silky web-like substance on branching points or at the base of leaves, and then at those spots the plant literally falls apart (entire branches will fall off with no prior warning, like they've been severed off from the inside outwards). The same treatment applies; take a q-tip dipped in rubbing alcohol and remove any white silk you find and spray the plant with a very mild dish soap solution, making sure you don't get too much of it on the soil.

I've heard a few people say that they use their jade plant as an aloe substitute, especially when the plant is mature and has a lot of leaves to spare. I can't imagine this working at all in their favour; there are no reports of jade plants being at all successful in promoting skin wound healing or relieving the pain of burned skin. Something tells me the placebo effect is hard at work here!

That's one crabby apple!

Species name: Malus baccata

Common name: Siberian crabapple

Location: Ontario

The fact that this tree is the Siberian crabapple should lead you to believe it's a non-native species, and you would be correct. Amazingly enough, we do have native species of this tree in Canada and the northern United States (and one separate species in the southeastern US around Florida and Georgia) despite them hardly ever being planted as ornamental trees. I would think they would be more tolerant to the kind of weather we get in Canada, but the Siberian species is often favoured because of the scent of the flowers. The fruit are attractive in the late summer and early fall, but don't seem to be favoured by any species of bird or small mammal. There are some that will eat them, but birds seem to prefer the trees for shelter as opposed to a food source.

The pollination requirements of any species in the genus Malus is quite interesting. They all seem to be self-sterile, and require cross-pollination between cultivars in order to produce fruit. While this might seem like a detrimental process (what's the likelihood of two different cultivars being in close proximity?), it actually would give the trees a huge benefit in nature because it would eliminate the possibility of inbreeding and hence reduce the effect of detrimental recessive genes (that might cause disease, susceptibility to disease, malformation, etc.).

The fruit of this tree are edible to humans, but few people actually consume them. They are great for making jams and jellies, but not necessarily the most healthy because they are quite tart and require a lot of sugar to make them palatable. Greaves at Niagara-on-the-Lake makes a great crabapple jelly, if you're ever interested in trying some. The fruit do look a bit like cherries from a distance when they are fully ripe, but have a completely different texture. These trees are also very popular to be used as bonsai trees.

The shrubby cinquefoil that's not a cinquefoil

Species name: Dasiphora fruticosa (formerly Potentilla fruticosa)

Common name: Shrubby cinquefoil

Location: Ontario

This plant is native to the Northern Hemisphere, but not to this area of Canada. The plant likely originated in northern Europe and Asia, and was introduced very early to North America. It has no potential to become invasive, and I would argue it has been incorporated in almost every way into our native flora of Ontario. It prefers growing in cool climates in subarctic or mountainous areas, and can tolerate dry conditions and saline soils. There has been a relatively intense effort to create new cultivars of this plant due to its attractiveness as an ornamental plant since it requires such little effort for upkeep. It is also very popular in Japan as a bonsai plant.

This plant is a great example of how DNA sequencing can show a different picture than what morphology tells us. The true cinquefoils, in the genus Potentilla, have compound leaves like this plant does but they have teeth along the edges while these leaflets are smooth. As far as morphology goes, that's probably not a significant enough difference to warrant putting a plant in its own genus, and so it was classified with the rest of the small, shrubby plants with yellow flowers and 5 petals that look a bit like buttercups (but you should now know why they're in the rose family!), and compound leaves with 5 to 7 leaflets. So far, DNA sequencing tells us that this is the only member of its genus, but that's probably only due to low sequencing effort; meaning that if more plants in the genus Potentilla and more plants in general that look like this one were sequenced, we would find that more species belong in this genus.

One negative aspect of this plant is that it acts as a prime food source and habitat for those pesky beetles that seem to become more and more numerous every summer in North America. Where there are more palatable food sources (like butterfly bushes, which are also numerous in North America) the bugs will prefer to eat those first, and just use the cinquefoil as a nighttime habitat. If you're into catching bugs by hand as a means of insect control instead of spraying, the hours right before sunset would be a good time to go out with an old pop bottle with a bit of vodka at the bottom to pick all of these guys off. The vodka ensures that they stay dead even when oxygen deprived (which these insects can actually tolerate for extended periods, which makes their control just that much more difficult).

Dawn Redwood: Critically Endangered?

Species name: Metasequoia glyptostroboides

Common name: Dawn redwood

Location: Ontario

This species of redwood is unique in many ways, only one of which being that it was only recently (well, in the grand scheme of things it's recent) rediscovered in 1949 after thoughts it had gone extinct in the late 1800s. It is native to a very small region in China, and within its native range there are only a few individuals of this species left so it is critically endangered. That being said, it's also an incredibly popular ornamental tree (gaining popularity in North America) so cultivated species of this plant will likely always exist even after the wild members of the population are long gone. Another unique aspect of this tree is that unlike it's close relatives, the Giant Redwood (Sequoiadendron) and the Coastal Redwood (Sequoia), this is a deciduous tree and a conifer at the same time. It produces cones like you would picture from a redwood or even a cedar, but loses its leaves during the fall like an oak or maple tree would. As you can see from the pictures, the leaves are like feathers, and it seems like they all appear overnight after the buds have persisted on the branches for many days or weeks. While you might imagine the debris from this tree would be quite impressive since it can be a huge tree (up to 200 feet in the wild) with many leaves, the leaf-like needles actually decay very quickly. It's certainly not the padded ground cover that you find in pine plantations!

The Dawn redwood is what we refer to as being a "monotypic" species, meaning that it is the only species that is currently alive in the genus. There are an estimated three other species that have once existed in the genus based on evidence from the fossil record. These trees seemed to be abundant in the early Paleocene, between 55-60 million years ago. The changing climate likely led to their demise, which seems to be repeating itself with the last remaining species. The Dawn redwood is also very sensitive to urban pollutants, so living in the city and trying to grow one of these outside is probably a losing proposition (and a good reason why urban encroachment is one of the contributing factors to the status of the last remaining wild population of this species). That being said, this is a popular plant species to turn into a bonsai, so growing it indoors can work well if you have time and patience!

These trees are a source of national pride in China, so much so that it's actually illegal to take branch cuttings from any one of the remaining 5,000 trees left in the wild. Unfortunately, cone collection is not protected in the same way so natural regeneration of these trees has essentially stopped. Once the mature trees in the stand die, the species will be extinct in the wild. The state of North Carolina has attempted to do its part by planting an enormous stand of Dawn redwood trees over three different sites. Their goal is to have 5,000 trees planted in various stages of growth by the year 2035, which is when the nature preserve is slated to open to the public. Hopefully this enormous undertaking will continue to thrive with changing national budget priorities! I would love to go see it someday.

Japanese quince: the best for bonsai

Species name: Chaenomeles japonica

Common name: Japanese quince

Location: Nova Scotia

You should be able to guess by the name that this plant is not only a non-native tree, but also that it is native to eastern Asia (Japan, China and Korea). The Japanese quince is somewhat related to the traditional quince in that it's in the same family, but other than that it's not closely related at all. The two can be used to make jams and jellies, but the Japanese quince is much less palatable on its own. It makes a fruit similar to an apple but is quite bitter and leaves you with an intense dry-mouth feeling. They do, however, contain more pectin than an apple and more vitamin C than a lemon and so are ideal for making jams. That being said, they are mostly grown in North America for their ornamental value as opposed to their nutritive value.

This specific species of Japanese quince (despite only one species of the genus Chaenomeles being the true Japanese quince, all three species in the genus are commonly referred to by the same common name; the way to tell them apart is by their size and the colour of their flowers) is ideal for the art of bonsai. This is a very arduous process of making a regular-sized plant very, very tiny through pruning and root growth restriction. The crown, or very top of the plant, is pruned as well as the tips of the roots to ensure that the plant remains a very small tree. Once the final product is achieved by the artist, it is typically planted in a pot with defined physical characteristics depending on the type of plant. I didn't realize that there was literally a rule book on traditional bonsai tree pruning and artistry! Once in the final display pot, the plant is continuously pruned to force the plant into a specific growth pattern (size and shape).

Other than ornamental purposes and the odd jam or jelly, this plant has no real commercial value. The Japanese quince is commonly attacked by the apple scab fungus but since the fruit are not typically consumed this is of little importance. In a cold environment this plant can suffer since it doesn't have much frost tolerance and the flowers are damaged easily.