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!

There's Rosemary, that's for Remembrance

Species name: Rosmarinus officinalis

Common name: rosemary

Location: teaching lab at Western

Rosemary is an incredibly unusual plant in the mint family (the Lamiaceae) because of its almost cactus-like lifestyle. The Latin name of this plant actually comes from its unusual ability to acquire nutrients in a hostile environment: "ros" for dew, and "marinus" for ocean. Not only is this plant incredibly salt-tolerant (with much of its native range in marine spray habitat), but it can acquire almost all nutrients it needs to sustain life from the air, where droplets of dew condense on the hairs and waxy coating of the leaves, where they are absorbed and used by the plant to make energy. In fact, rosemary is so drought-tolerant it can go without being watered for months. This makes me seriously wonder how I managed to kill my rosemary plant in a single month; something tells me I over-watered and should only have been misting it. It was one of those strange rosemary Christmas trees, so it might have also been root-bound. Yep, let's blame it on being root-bound. Then it's not my fault. :) Rosemary is native to the Mediterranean, where it still commonly grows in the wild. It is also a popular ornamental species, and some rosemary plants are hundreds of years old.

Rosemary is one of the most popular herbs to use in cooking, especially in meat dishes because it has such a distinctive flavour. In fact, what most people don't know about rosemary is that the flavour is best brought out of the herb when you "spank" it (for a refresher on why you might want to spank an herb, refer to my blog post about mint HERE) and then burn it. Yep, that's right. Burn it. One of the best ways to use rosemary is on barbecued meats where you poke some sprigs of rosemary into the meat and just let them singe and burn until the meat is cooked to desired done-ness. Take the burnt pieces out of the meat with some tongs before serving (or just eat it. Burnt rosemary won't kill you), and voila! Smoky rosemary-infused meat. Yum, yum. Rosemary also pairs really well with mustards, because the acidity in the mustard also brings out the flavour in the rosemary leaves. Interestingly enough, mustard is native to almost the same geographic region that rosemary occupies. There might be something to this mustard-rosemary pairing...

As the Latin name suggests, rosemary has been used for centuries (some people have argued for many millennia, but the evidence for rosemary use only dates back to about 3,000 years ago. Yeah, "only.") as a medicinal plant, mainly to improve memory. It wasn't just used to improve "brain memory," either, but also to improve muscle memory. After someone suffered a stroke in the Middle Ages, a salve of rosemary leaves ground into wine was applied to the site of muscle paralysis as it was believed that doing so would help the body "remember" how to move the paralyzed muscles. It probably didn't work very often, but at least you would smell good :) That type of concoction was also consumed orally to treat gout (it was most famously used in this manner to treat the Queen of Hungary Elisabeth of Poland in the 1300s). Don Quixote also used rosemary leaves in his miraculous balm of Fierabras, which was reported to heal anyone that drank it. This very likely had at least SOME effect on the body, as the secondary compounds of rosemary are highly antimicrobial. Back in the 1100s and 1200s, before the discovery of penicillin, any kind of wound that got an infection would almost certainly lead to death. By either drinking this highly antibacterial (and antifungal) beverage or applying it directly to the wound, it would help protect it from infection. For some wounds it would have been irrelevant as they would be severe enough to kill you anyway. But for other more minor wounds, it might have made the difference between life and death. It's always nice to know when some of the folklore of popular tales is actually biologically possible!

Because of its historical medicinal use in improving memory, rosemary sprigs also play a leading role in wedding and funeral traditions around the world. In funeral bouquets that are scattered on graves, rosemary serves as a sign of remembrance for the dead and a way of honouring their memory. Across much of Europe, rosemary is still incorporated into the wreathes in Remembrance Day ceremonies, and also in war commendation ceremonies (especially if these are to commemorate the brave acts of a soldier who died in battle). In wedding ceremonies, they represent remembrance of loved ones that passed before the time of the ceremony and also to remember the life the couple spent apart before they were united in marriage. This eventually caused the evolution of rosemary from an herb of remembrance into an herb of love, and now sprigs of rosemary are considered to mean love and good luck in marriage. The sprigs of rosemary in the bride's bouquet would be planted in the ground, and if they grew it would be a sign of good prosperity and good luck. If they didn't grow...well, I guess it sucks to be you. Hint: dip it in some rooting compound first and problem solved. See, there's always a way to coerce luck into working out in your favour. Just takes some work!

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!

Let's play a game: ID this plant!

UPDATE: The general consensus reached for the ID of this plant is Thymus pulegioides. This ID still doesn't feel right to me, but since I'm not a plant expert and the two that both came up with this ID are, I'm going to defer on their expertise and say that's what it is. At least, something close. The common name of this plant is broad-leaved thyme and sometimes lemon thyme (although, that common name is applied to just about any plant that looks like thyme that smells even remotely lemony, which is 5 or 6 different species). Thanks for playing, everyone! And thanks for Sophie and Matthew for the help via Twitter.

Species name: Lamiaceae sp.

Common name: plant in the mint family

Location: Ontario

I've been toying with the identification of this plant for a few days now, and I just can't seem to get it right. So instead of me identifying it, I'm opening the floor. Know what this plant is? Drop me a line in the comments section!

Instead of talking all about one particular species, I figured I'd talk about at least what I know for sure to be true: this plant is most definitely in the mint family, or the Lamiaceae. There are two major distinguishing features for this family. The first are the flowers: the petals are fused at the base into a tube-like structure, and at the end are modified into a large top petal and an even larger bottom petal. Sometimes, as in this example, the bottom petal retains morphological characters that would lead you to believe it came from the fusion of three petals (which it did) in the form of lobes on the petal edge. The second major feature that leads me to the general identification of this being a plant that's a member of the Lamiaceae is pointed out by the arrow in the bottom photo, the square stem. If a plant is in the mint family, it has a square stem. For some species, you have to use your imagination a bit more than others for how this rough round shape is actually a square, but more often than not the stem is a clear square shape in cross-section.

The leaves of this plant are smooth on both the top and bottom surface, and the leaves are incredibly small and lack teeth, all unusual characters for the mint family. One of the reasons why members of this plant family are so aromatic when the leaves are crushed is because of the tiny hairs on either the upper or lower surface of the leaves (or sometimes both) called trichomes that have a tiny oil droplet at the tip. This oil droplet is meant to deter herbivores, since in large amounts they taste downright nasty, and in fact most are carcinogenic. You don't have to worry about getting cancer from basil or oregano, though! Since humans are so large, you would literally have to eat a pound of basil a day for the chemicals in the essential oils to have any negative effect. The very reason why we started to use herbs and spices in food is to exploit these essential oils, which even in small amounts have very potent antimicrobial effects, and to kill food-borne bacteria before consuming food prior to refrigeration.