You put your left flower in, you take your left flower out...

Species name: Physostegia virginiana

Common name: obedient plant

Location: Western University campus

I didn't realize until after I had taken and water-marked these photos that I had already blogged about this plant once. If you'd like to go back and read the first version, you can do so HERE. If you'd like to read a "better than the last" version, keep reading! :)

The obedient plant is one cool plant. Endless hours of entertainment if you're lost in a prairie (more on that later). The native range of this tiny plant is quite impressive, ranging from the northernmost edge of the temperate forest in Canada all the way south to parts of the (very small bit that's remaining) tropical forests of Mexico. If grown in Canada it illustrates the reason why I should have made the species status diagrams with a "common, native, invasive species" combination because it spreads very quickly and can dominate a landscape in just a few years. Where there is snow during the winter the plant will die off, but because of the extensive underground network of rhizomes it will pop back up in the spring and produce more of the beautiful flowers. If you're thinking of planting this species in your garden, then go ahead and do so if you live in my area. It's a native species, and it's never a bad idea to plant a native species! You might want to reconsider, however, if you have an intense aversion to weeding (it will spread, trust me) or if your yard backs onto an Environmentally Significant Area. For those locations, even the slightest change in dominant species (such as providing a source for a seed bank of a weedy, although native, species) could spell disaster for the area. Always make sure you keep in mind what is around you before making major changes to the landscaping in your yard.

This species is one of the best examples of a member of the mint family, or the Lamiaceae. The stems of this family are almost always square, while nearly all other plant stems (the notable exception are the sedges) are round in cross-section. You can see the ridges of the square stems of this plant clearly in the third picture, above. The leaves are also characteristic of the mint family: they are simple leaves with teeth (some members of the mint family have leaves with smooth edges) that emerge from the stem directly across from each other. The next node up (or down) on the stem will also have opposite leaves but they will be at right angles to the previous level of leaves. You can also see what I mean by this in the third photo. The flowers are also very characteristic of the mint family, although different varieties of this plant have been modified in different ways (sometimes quite drastically) to be different than the so-called "wild type." A wild type plant is a plant that would be found growing in the wild without having experienced any intervention by horticulturalists (or, in the case of edible plants, farmers). The group of plants above are pretty characteristic of the wild type of this species: purple-pink flowers, the flower petals are joined at the bottom and form a structure that looks like two lips at the edge of the flower, darker purple or purple-pink splotches on the bottom lip, and the sexual parts (most noticeable being the stigmas) being attached to the top lip of the flower. This "two lip" morphology isn't done just by chance by the plant; it's actually a flower shape that has co-eveolved with the choice pollinator of this species: bees. Something that you may or may not be aware about bees is that they can't see colours like we see colours. Everything green looks a very dark blue to them, so picking out flowers from a sea of blue-black is difficult, especially when you can't see them. Bess are special, though, because they can see a wavelength of light that we can't see: ultraviolet light. This means that anything that's purple, or even purple-pink, will glow when a bee looks at it. The flowers themselves aren't quite purple, so merely act as lightly glowing beacons in the sea of blue-black plant material. This is enough to entice the bees over, but the dark purple patches on the lower lips of the flower is what really brings the bees over. The bees see the structure of the flower, and use the lower lip of the flower like a landing pad (those darker splotches would be like the landing lights that pilots use to land planes on runways at night). The bee would wiggle around, trying to get its head as deep into the flower tube as possible to access all of the yummy nectar. This would cause the bee's back to rub up against the stigmas of the flower (located on the top lip, which you can see in the fourth and fifth pictures above), which would dust pollen all over the bee's back. Once the nectar is gone, the bee would fly to the next flower, do the same thing, and transfer all of the pollen from its back onto the stigmas of the next flower, ensuring successful cross-pollination. Sneaky little flower! But also quite a smart little flower.

So why is this plant called the "obedient" plant? Well...it stays where you put it. Huh? The flowers actually have the ability to swivel around the flower stalk, and when the flowers swivel into a new position they stay that way. Check it out below:

In the top photo all of the flowers are pointing towards the ground, which is actually pretty common in this species once the flower heads flop over (often they grow too quickly for their own stems to support them if conditions are ideal). In the bottom photo I took two of the flowers by the base and swivelled them around to point straight up. They'll stay that way for up to a minute, then flop back to their original position. If you give the flowers a break, you can move them back and forth multiple times before the plant will just give up on those flowers and dissolve them off the flower stalk. Only the best are allowed to set seed!

Mints on Monday

For this blog, like the blog post I wrote about different species of geraniums (which you can read about HERE), I'm going to profile 4 different species (well, two species and two hybrids; sometimes only one species, two hybrids and one variety depending on who you ask) of mint. These plants are all in the genus Mentha, which is the "true" mint genus (there are other groups that are called mints but that are not in the genus Mentha; these would be close relatives of this genus that would be in the mint family, the Lamiaceae). The four types of mint I'm going to profile are: orangemint, menthol mint (or peppermint), spearmint, and mojito mint. The photo below is a photo of all four of these plants on display in the teaching lab:

You'll notice that I conveniently numbered all of the pots in the order I'm gong to profile the plants :) I love it when I plan ahead. So let's begin!

Species name: Mentha citrata (sometimes Mentha arvensis var. citrata)

Common name: orangemint

Location: teaching lab at Western

Orangemint is sometimes only known as a variety of water mint (Mentha arvensis), but I like to consider it a separate species. Currently, whether it's a species or a variety is still up for debate since DNA studies can't quite rule out either option. Mints are notorious for being able to cross-pollinate each other regardless of what species they are, so there is a lot of genetic contamination of most "wild" populations, and greenhouse populations (unless bred to be sterile) are no better. Due to the huge difference in texture and shape of the leaves, I like to think it's a separate species. It's likely native to the Mediterranean (although this is debatable since it has been cultivated for so long in so many other locations it's hard to tell), and is potentially invasive in some areas (but not southwestern Ontario where I am).

So what is different about the texture and shape of orangemint leaves? Well, for one they're rounded. The reason why "spearmint" is called SPEARmint is because of the shape of the leaves: almost all leaves in the genus Mentha are very pointed at the end and have sharp teeth along the edges of the leaves. Right away this plant is definitely an oddity in the genus. The leaves are also much fleshier than other species of mint, and have a bit of a water storing capacity even if they aren't true succulent plants. This characteristic makes orangemint pleasant to eat...to a point. It has a much more satisfying chew to it than other species of mint, the leaves aren't as hairy and so don't give you as much of a "hairy tongue" feeling when you're eating it, but BOY does this plant ever pack a punch. Unfortunately, despite the leaves smelling like an orange grove in Florida or California, they don't taste a bit like what they smell. In fact, after chewing the leaves for a few seconds it's downright unpleasant.

Like most members of the mint genus, this plant has a dirty little secret. It has been used for centuries in a tea-like preparation as a medicinal beverage, and has been used to help everything from stomach aches and nausea to preventing or treating seizures. The pure extracted essential oils do show a lot of great medicinal potential for a variety of medical ailments (although not sold commercially for any disease, disorder, or symptom), but it's secret is that it is a potent carcinogen and mutagen. In fact, consumption of too much orangemint tea when pregnant will almost certainly lead to miscarriage. If it doesn't, there is a strong possibility for severe developmental deformities in the fetus (or embryo, depending on time of consumption during pregnancy). Because the compounds in orangemint extract are mutagenic, they cause DNA mutations which are irreversible. Always use extreme caution before consuming any "herbal" remedy during pregnancy. Just because it's "natural" doesn't mean it's safe!

Species name: Metha x piperita

Common name: menthol mint, peppermint

Location: teaching lab at Western

Next up we have the plant most commonly used to create the plant extract known as "menthol," peppermint. There are actually numerous species of Mentha that are used for this purpose, but the specific cultivar referred to as "menthol mint" is used most commonly because it has been bred to contain very high concentrations of this chemical. Peppermint is most probably native to Europe (there's the same problem as with orangemint for determining where exactly this species is native to based on the incredible amount of cultivation of this hybrid around the world), and is incredibly invasive in almost all areas it's planted.

One of the great things to note about many species of mint is that they are sterile hybrids. This means that the plant produces flowers, but these flowers don't have the ability to produce seeds. This is a great characteristic, especially in a potentially invasive species, because it means that the chance of this plant getting out of control can potentially be avoided. Unfortunately, there are two problems with this idea when it comes to peppermint: one, this hybrid isn't sterile (oops); and two, this plant produces below-ground biomass almost as quickly as it produces above-ground biomass. Peppermint plants produce huge numbers of rhizomes, which can grow underground and seek out new pockets of nutrient-rich soil to send up shoots to grow. This can cause the exponential growth seen in some areas, where for every one stem you pull out of the ground it seems like the plant sends up two more. Definitely a never-ending battle, and that mixed with the fact that it produces seeds that can blow away in the wind to create new plant colonies, means this plant is a very successful invasive species. Because of the fact that almost all species of Mentha have the potential to become invasive, you should never, EVER plant this directly in the ground, and especially not if you live near an environmentally significant or environmentally sensitive area.

Aside from the essential oil extraction, this plant is used for a remarkable number of uses. First, it is the most popular culinary additive in the world, especially in confections. In fact, there's recent evidence that its use goes back to 10,000 years ago in southeast Europe where it was found with other archaeological artifacts that suggest it was used to flavour food. It has also been used for medicinal purposes, as it is one of the most effective treatments for any kind of digestive issue from upset stomach to irritable bowel syndrome (IBS; there was a recent clinical trial that showed that the consumption of some amount, don't remember how much, of purified peppermint oil completely eliminated symptoms of IBS in 75% of women tested, and decreased IBS symptoms by at least 50% in all 15,000 women tested! That's incredible!). Now you know why restaurants give you an after-dinner mint! It decreases the feeling of being bloated, by encouraging the formation of small gas bubbles in your intestines. Might make you a bit gassy after a large meal, but I think that's better than laying on the couch groaning for an hour or two! Purified peppermint oil has also been used as a natural insecticide, as even in small quantities it prevents insect herbivory on most plants when applied as a spray. Purified menthol has been used as a medicinal additive for decades, most notably in muscle creams to give that minty smell but also a cooling sensation (which is why muscle rubs with a high concentration of menthol work incredibly well as methods of decreasing the itch associated with mosquito bites! The cooling sensation takes away the itch). Another good thing about peppermint oil is that it is one of the only members in the genus that does not display carcinogenic or mutagenic qualities, even in higher concentrations than one would ever be exposed to. In fact, peppermint tea is one of the most widely recommended "herbal remedies" for mild cases morning sickness.

Species name: Mentha spicata

Common name: spearmint

Location: teaching lab at Western

Spearmint is another incredibly commonly grown member of the mint genus, and like peppermint is incredibly invasive. It is not a hybrid so does produce viable seeds, but it also produces those same vigorous underground rhizomes like peppermint. Not a good combination! This species is native to Europe and southwest Asia, but is now grown commercially around the world. A very versatile plant, but one that should be treated very carefully; the flowers should be pinched off the plant before they're given time to set seed to prevent the spread of this species, and it should never, ever be planted directly in the ground.

Often with mint species (and other species used as herbs in the Lamiaceae like basil, rosemary, sage, and thyme), it is suggested that the flowers be pinched off before they're given much of a chance to develop. This actually has very little to do with the reproductive cycle of these species but rather with their use to humans. All plants display a phenomenon referred to the "allocation of resources" during all points of the plant life cycle, but this is more pronounced during flowering and fruiting. You'll notice perhaps with a lot of fruit trees that once the fruit starts to develop on the tree the leaves will turn and fall off at even the slightest change in climate without damage to the fruit. This actually has nothing to do with the health of the tree and everything to do with the attempt to give your offspring a healthy chance at being able to disperse and reproduce. Because (for example) a peach takes so much energy to produce a big, fleshy fruit around the seed, if the plant is under any kind of stress it will try to reduce the stress without impacting the next generation. This is why sometimes (especially nearing the end of the season) the leaves on the plant suffer. The same thing happens with highly fragrant plants once they start to produce seed. The seed producing takes much of the plant's resource allocation away from the production of secondary compounds (what gives the plant the smell), and instead puts all that energy into seed production. Great if you're a seed and want a good chance at being able to grow, but bad for you as a gardener if you want basil (or spearmint) with flavour! For this reason, make sure the flowers are pinched off the plant as soon as you see them start to develop. This will confuse the plant, and it will forget it was ever attempting to reproduce, ensuring that your leaves retain their potent flavour.

Like with peppermint (a hybrid created from spearmint), the essential oil of this plant shows very little mutagenic activity when tested. It is also effective medicinally against stomach ache, but so far hasn't shown much promise in the treatment of chronic digestive tract diseases or disorders. This is probably due to the fat that spearmint essential oil contains very little menthol and menthol-like derivatives. There has been the suggestion that spearmint oil can be an effective treatment for hirsutism in women, otherwise known as "excessive hairiness." Spearmint oil has anti-androgenic qualities, which means it can interfere with free testosterone in the blood. For those women that produce too much testosterone, this might be an effective treatment in reducing the amount circulating in the blood. Unfortunately, there are severe side effects associated with prolonged ingestion of concentrated amounts of spearmint oil such as kidney and liver failure. Until the dose-dependent and long-term effects can be minimized, this treatment won't ever make it on to the approved drug list in any country.

Species name: Mentha x villosa

Common name: mojito mint

Location: teaching lab at Western

Of course, we save the best for last. For those of you that have ever partaken in the consumption of the national drink of Cuba, you will likely have never had it made correctly :) Most places (or people) that make mojitos make it with regular old "mint," which is likely either peppermint or spearmint. This is all fine and dandy, but have you ever had one of those leaves or a piece of a leaf get sucked up in your straw and you have to make the decision to either eat it or spit it out? I bet you probably chose to spit it out, because of the "mouth feel" of the leaf. Both peppermint and spearmint leaves are very hairy, and give you a bad case of the "fuzzy tongue" if you consume a lot of it. True mojito mint, on the other hand, has leaves that are almost completely smooth which completely eliminates the fuzzy tongue feel. A great culinary advancement when it comes to tropical beverages!

This hybrid probably really did arise in the Caribbean, perhaps in Central or South America, and is referred to in Spanish as "yerba buena" or the "good herb" (this is especially true in Cuba). Many species of mint store at least some of their potent essential oils in glandular trichomes on their leaves, which is why they are aromatic just by lightly shaking the plant or touching the leaves. This is not the case in hairless varieties (or species), so the leaves must be treated carefully enough that you don't just get the "taste of plant" when you use them, but rough enough that you actually get the essential oils released from the leaf. This is done by muddling the leaves of the plant with sugar, sometimes alone depending on the species, to get the leaves to release their essential oils. When only using mint as a garnish and not in the drink itself, you always "spank" the mint to get it to release the essential oils.

Mojito mint is an example of a sterile hybrid, so this plant doesn't produce viable seeds (in fact, the plant rarely produces flowers which is also a benefit for those that want to use it for the fragrant leaves). It does still produce those vigorous rhizomes, so care does need to be taken when planting it. This is especially true in tropical and sub-tropical areas as it is drought tolerant, heat tolerant, and has a prolonged growing season which makes it a potentially successful invasive species. This hybrid is actually so vigorous and withstands harsh conditions so well that our plant actually came back after a cold Canadian winter!

To Zing or not to Zing, that is the question

Species name: Zingiber officinale

Common name: ginger

Location: teaching lab at Western

Ginger is one of the most commonly used spices around the world, and one that many, many people love the taste of (you can count me as a non-member of that group; I personally HATE ginger). It is a tropical spice (and hence why it's a spice and not an herb), and is now most commonly grown for export in India, China, the Philippines, and Jamaica. There are many other countries that grow a lot of ginger, but those are countries that also use a lot of ginger in their traditional cooking (Nepal, Nigeria, Cameroon, Thailand and Bangladesh) and so only a small amount of the total harvest would be available for export. Despite being one of the most commonly cultivated spices around the world, very little is known about the wild populations of this species of ginger (there are four other species in the genus that are commercially sold as "wild ginger," but be careful; the native Canadian species known as wild ginger, an unrelated species to this group, contains potent carcinogens and should never be consumed) throughout its native range in southern Asia around Thailand and Indonesia. There is the presumption, however, that the population sizes are declining due to habitat loss.

Ginger was once believed to be closely related to grasses but now has its own order, the Zingiberales, within the group known as Commenlinids. These are a unique grouping of species within the monocots that includes all grasses, bananas and their close relatives, spiderworts, water hyacinths, and the palms. Quite a diverse group of plants, and a group that most people probably never would have assumed went together. I don't know about you, but water hyacinths (popular ornamental pond aquatic plants with a large bulbous "bladder" at the bottom of the leaves to keep them afloat) and palm trees don't belong in the same group of plants in my mind! But when we compare DNA sequences, these groups of plants do, in fact, make a genetically related group called a monophyletic group. Pretty neat what DNA sequence analysis can show us! Is there something, other than DNA sequences, that demonstrate that these seemingly drastically different plants belong in the same group? Well now that we know they belong, we do actually notice some biochemical similarities between these plants. The most striking of these similarities is the production and storage of ferulic acid in the cell walls of the plant tissues. This type of acid is only produced in this group of plants, and the best part about ferrulic acid? It glows under UV-light. Granted, it is produced in such low quantities that even if you put a grass plant or a palm tree under UV-light you wouldn't notice it glowing but this acid can be extracted and concentrated and used to make things glow. Pretty neat! Ginger plants do share many characteristics with grasses, so I can definitely see why it was assumed they must be very close relatives. They both have the same morphological features with leaf growth and development as grasses: the leaf sheath wraps around the stem (and the stem is actually just composed of concentric leaf sheaths that grow inside one another), forms something called a ligule at the top of the sheath that helps prevent the plant from plant diseases (it acts almost like a piece of tape that prevents anything from getting down between the sheath and the rest of the stem and can be seen clearly in the third photo from the top), and the leaf blade which is the "leafy floppy part" that comes off the stem. The most interesting part about ginger and grass leaves is that each species has its own ligule; they're almost like identification "fingerprints" that can be used by botanists to determine species. Pretty neat that no two species have identical ligules.

If you're an avid reader of my blog (which you should be if you aren't!), you'll have noticed something right away, before barely scrolling past the pictures. The last name of this plant, "officinale," must mean it has medicinal properties! If you assumed that, you would be correct. Common ginger has been used for thousands of years as a medicinal plant, reportedly being able to treat anything from dyspepsia to constipation and colic. Modern scientific research today shows that the rhizome of the plant contains a group of chemicals called gingerols, and these chemicals stimulate the digestive system and cause an increased amount of motility of the gastrointestinal tract. Ginger extracts would definitely help with mild indigestion or mild cases of constipation, but more severe gastrointestinal diseases or disorders have not yet been evaluated for efficacy. There has also been a lot of use of ginger in treating muscle pain associated with intense physical exercise (consumed in China during times of intense building in the 1200s to 1800s, and trekking for materials for these construction projects) and arthritis, and this has also been shown to be somewhat effective in clinical trials. When ginger extract is consumed after a workout, muscle pain post-workout can be reduced by as much as 25%. The catch: ginger extract must be consumed daily, workout or no workout, in order for this effect to be noted. In Canada and the United States, ginger and ginger extracts have made it onto the coveted "generally regarded as safe" lists. So does this mean that ginger is completely safe? Well, like all herbal remedies, you should always check with your doctor before taking them. Ginger in particular causes an increase in bile production as a way of promoting faster digestion. This isn't a problem for most people, but those most sensitive to an increase in bile production will report having heart burn after eating ginger. In cases where someone is sensitive to bile in that they commonly get gall stones, eating ginger every day or taking pills of ginger extracts would be really silly because it would exacerbate the problem. Those with ulcers or inflammatory bowel disease may react badly to large amounts of ginger because of the increased stimulation of the digestive tract, but these reactions are rarely enough to land the person in the hospital (but are unpleasant enough that it is rarely done a second time!).

Despite ginger being such an important plant to many countries around the world, it has yet to make it onto any kind of "national or state/provincial plant" list. This is really too bad for ginger; people who only appreciate ginger for its flavourful rhizome will never get to fully experience the greatness that is ginger. The flowers are absolutely stunning to look at (so delicate and almost transparent the tissue is so delicate, hence my difficulty photographing them), but also could practically knock you over with their intense sweet scent. The flowers open in the evening to attract their nocturnal pollinators, and then are wilted and shrivelled before the evening of the following day.

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.

Sandra's Garden: This hawkweed has spots!

I've been sitting on this blog post for a couple of days because I've been really unsure of the correct ID for this species. I was pretty sure I had it once...but then changed my mind. Then I was pretty sure I had ID'd it correctly again...but then changed my mind again! Now I've got it. I think. If you think I'm wrong, feel free to point it out in the comments section and lead me to a more appropriate name. This is one of the reasons why I hate trying to ID "dandelion-like flowers"--they're just so gosh darn hard to get the right name if you don't have a microscope and a full identification key handy!

Species name: Hieracium maculatum

Common name: spotted hawkweed

Location: Sandra's garden

This species of hawkweed, incredibly common throughout Europe where it is native, is also now becoming more and more common in Canada. Here it's considered a weed since it thrives in highly disturbed areas which include that garden you just dug up to plant new flowers, or the area around where you just cut down the tree and don't know what to replace it with. In Sandra's case it's growing right beside her driveway (made out of gravel, not asphalt), but it's also serving as a great example of what the definition of a "weed" is: a plant that's growing somewhere where we don't want it. Sandra's got a great philosophy towards gardening: "if I like the plant, then it gets to grow." While most of us would have ripped this plant out a long time ago because it looks far too much like a dandelion for our liking, Sandra lets it thrive behind a rock that serves as a buffer between the driveway and the mulched garden. Enjoy your time while it lasts, little plant!

Hawkweeds are some of the most successful plants in disturbed areas because of the way they reproduce: they make asexual seeds. This phenomenon is incredibly unusual overall in the plant kingdom, and when a plant decides to reproduce asexually (which in itself is actually quite common) or clonally it rarely chooses to do so via seed production. Rhizomes, tillers, offsets or offshoots, suckers, foliar embryos, splitting, layering--all of these are common phenomena displayed in various plant species (sometimes even in groups as large as families) that rarely results in a seed-like structure being produced. In fact, plants that reproduce asexually prefer to do this over reproducing sexually but yet retain the ability to do so if growth conditions change. Reproducing asexually is much faster than producing seeds, and seed production is very energetically taxing on the plant (sometimes even killing the plant afterwards!). On top of that, you never quite know what kind of gene combination you're going to end up with since you shuffle all of your genes and they are randomly distributed (along with your mate's genes) into the seeds; each seed still gets one copy of each gene (or two, or four, depending on the plant...) from each parent, but each parent can have two different copies. Which one your offspring gets (you might have two good copies, one good and one bad copy, or two bad copies) is luck of the draw. Why would you risk giving your offspring a bad copy of a gene when you can just pass on all of your genetic material, exactly as it is, to your offspring so they can thrive like you do in the environment you're in? Seems like a no-brainer. But when the environmental conditions change and you are challenged as a plant in your environment, you might decide it would be best for you to roll the dice and take a chance at shuffling your genes so your offspring have a better chance in this new environment. Thus, seed production. But ASEXUAL SEEDS? This just seems crazy.

And for some plants, deciding whether to produce asexually or sexually is way too much work, and since your gene combination works for you it should also work perfectly well for your offspring, aka your clones. Almost the entire genus of Hieracium species reproduce exclusively via asexual seeds that are dispersed in the same way that dandelion seeds are in the wind; this process is called apomixis. This leads to the debate of "what is a species?" which is currently getting quite heated between experts that study this plant in Europe and in the United States. Some say that each clone should be considered a different species, since if you don't reproduce sexually it's impossible to tell who is your closest relative (a perfectly valid argument; one that has been raised in many other plant, animal and fungal species). That would give us about 10,000 species of Hieracium. Others argue that species should be defined based on broad morphological differences, which would give us about 800 species of Hieracium. Just a little difference! No matter which way you choose to define species, I think it's safe to say that there's a lot of them. If you tried counting to 800, it would take you a while; that's my definition of "a lot." There are a lot of species of Hieracium. There. Problem solved!

So what are hawkweed species good for? Absolutely nothing (sorry for just getting that song stuck in your head)! Actually, the plants themselves and the seeds are important food sources for a lot of animals, but one moth in particular: the large yellow underwing moth. This insect species is a great example of an insect that is expanding its range in response to warmer, shorter winters. Prior to the mid-1980s it was found exclusively in Europe and the Middle East, but after its introduction to Nova Scotia by accident in 1985 it has spread all the way to California and Alaska in 20 short years. Prior to that it had never been found further north than the southern edges of Russia! A pretty incredibly feat for a bug.

The Pac(aya) Man tree

Species name: Chamaedorea tepejilote

Common name: pacaya, guaya, palmito dulce

Location: Dominican Republic

The pacaya palm, sometimes called the pacaya grande depending on where you're from, is native to Central America from Mexico south to Panama. It is one of the most common palms native to the Americas, second only to Washingtonia palms native to California (which are planted in massive numbers as ornamental palm species). Because they are so attractive, pacaya palms have been transported throughout the Caribbean for use as ornamental species, but you will rarely find them outside of the Western Hemisphere. Unlike many palms, this species is highly shade tolerant, and actually "sun intolerant". The leaves, as you can see in the image above, become yellowed and sunburnt very quickly when exposed to direct sunlight so they are best planted in the shade of other trees.

The variety of this tree most commonly grown as an ornamental species are types that "cluster," as opposed to single stems. In the wild, this is incredibly rare but in cultivation it's common. It leads to a much more attractive bunch of stems, as opposed to one tall and spindly stem. The other benefit of growing this variety is that it is much more resistant to hurricane damage, since it is more difficult to disturb a clump of plants all connected via underground rhizomes than it is to disturb one lone tree.

This tree is an example of one of the many palm species that are dioecious. This means that there are separate male and female flowers on different plants; this is exactly like with holly plants, where you will only have red berries produced on female plants if the male is present (which doesn't produce red berries). The determination of "sex" in a plant is quite different than it is in a human; instead of being determined by a chromosome like it is in humans (with human females being XX and human males being XY) and it's instead a cluster of genes on a chromosome. Certain alleles, or copies of the gene, determine either "maleness" or "femaleness". The plants pictured above are likely male; in the entire cluster there was no evidence of fruit being produced, which occurs during all months of the year.

The seeds when ripe are apparently edible, as are the flowers (with the female flowers tasting significantly better than the male flowers, apparently). I would highly recommend you avoid eating any palm fruit unless you are absolutely positive of the species identification; many palm fruits are deadly toxic. In El Salvador and Nicaragua, the pickled female flowers of this plant are seen as delicacies and are served only during special meals.