Tuesday, July 31, 2012
Species name: Stachys byzantina
Common name: Lamb's ears
This plant is one of the few that we use as ornamental plants in northern North America that is native to the area around Armenia, Turkey and Iran. The climate there is so different from what it is here that most plants native to that area would never survive the winter. This is one of the exceptions; if the above-ground portions of the plant cannot survive the winter, the roots can regenerate shoots and regrow the next growing season. This does mean that as our climate warms, the range of this plant will expand much further north, and becoming much more likely to be invasive to certain areas.
The medicinal potential of this plant is huge, especially considering where infections are headed lately. It seems like there isn't a month that goes by that a major hospital in Canada or the United States (or in any other country, for that matter) doesn't have an outbreak of a drug-resistant bacterial species. This is becoming more and more dangerous, since more species are becoming multi-drug resistant. One such species of bacteria that has been in the news recently is drug-resistant Staphylococcus aureus. Historically, drug-resistant Staph infections could be treated with very strong antibiotics but now even those are no longer effective. For this reason, more drugs that are effective against this bacterial species need to be discovered, and it also needs to be an ongoing process (since bacteria can produce a new generation so quickly, drug resistance also evolves incredibly quickly). Lamb's ears extract contain a number of chemicals that, when in synergy, demonstrate the ability to kill multi-drug resistant Staphylococcus aureus. It's still in the early stages of drug development, but probably over my lifetime the drug will be released for select use only for multi-drug resistant Staph.
Monday, July 30, 2012
Species name: Rudbeckia hirta
Common name: black-eyed Susan, yellow ox-eyed daisy
Black-eyed Susans are spectacular flowering plants native to southeastern Canada all the way south to Florida and Texas in the United States. There are four sub-species designating populations of plants in various locations, since the species range has become non-continuous due to land use change. It's an incredibly successful competitor and thrives in disturbed areas, so is often the first plant to colonize a recently abandoned field. Despite being able to out-compete almost all early successional field species, it does poorly in shade and so once shrubs and trees start to colonize the area it will quickly die out (or only remain in small patches). Anyone who has ever planted this plant in their garden knows about its ability to quickly colonize an area; keeping a patch of Black-eyed Susans under control feels like a losing battle (partially because, by definition, backyard gardens are disturbed areas which means this plant does exceptionally well).
Medicinally, this plant was used in almost the same way as the purple coneflower, Echinacea. The Ojibwa people used a paste-like liquid made from ground roots mixed with water as a treatment for snake bites, and made a tea-like infusion from the leaves and roots as a treatment for worms in children. The Menominee and Potawatomi people used the natural diuretic properties of this plant to flush toxins from the body. Because this diuretic effect is real, caution should be used when using this plant as an herbal medicine; over-use can result in severe dehydration which requires hospitalization. If this is not caught in time, permanent kidney damage or even death can occur.
Sunday, July 29, 2012
Species name: Phalaris arundinacea
Common name: reed canarygrass, ribbon grass
This is one example of a plant where, in hind sight, I wish I had made a species status diagram that included "invasive" as a category with "native". This species of grass, native so Ontario and the surrounding area, is incredibly invasive and downright impossible to eradicate once established (at least, without the use of harsh chemicals). It produces chemicals in the roots that prevent competitors from establishing in the same area, while at the same time being incredibly successful at reproducing both sexually by seed and asexually by thick underground rhizomes. Anyone who has ever tried pulling this plant out of the ground knows about the thick rhizomes! The natural form of this plant is solid green, but horticulturalists have bred this plant to be variegated, which has allowed this plant to become an attractive garden plant, especially for moist garden areas. Despite thriving in boggy areas it is also incredibly drought-tolerant once established, and has also been suggested as a good phytoremediator since it can sequester contaminants from the soil.
The reed canarygrass has also been suggested as a possible candidate for burning as biofuel, since it is so fast-growing. It has recently been used in trials of contaminated soil rehabilitation mimicking the Chernobyl or Fukushima nuclear disasters, to experiment with different plants that can be used to clear contaminants out of the soil. This plant, along with the common sunflower and a few other garden plants, have actually shown great promise. One of the neat things about plants is that they can be genetically manipulated to store radioactive waste in specific parts of its plant body while not in others. This means that, theoretically, you could get a sunflower plant to store radioactivity in its leaves that you could harvest and dispose of safely, while you could also harvest the seeds to be used for food, grain, or for oil production. Since the radioactive waste wouldn't ever make it to the seed, the seed would be perfectly safe for human consumption. I'm not sure how many of us would knowingly eat "Fukushima sunflower seeds" at a baseball game, but it's a neat idea. Still many, many years away from being a viable ecological treatment since so much safety testing must be done. By the time it was approved, I'm sure there would be other ways of remediating the soil that would be favoured instead.
This plant contains incredibly high concentrations of the chemical gramine, which causes brain damage and death in sheep who consume it. This effect isn't always translated to humans, but still probably a good idea to make sure this plant is always out of reach of children and beloved pets. Levels of hordenine have also been reported (a chemical present in high concentrations in germinating barley seeds, but denatured at the high temperatures used in malt production, for those of you who make beer in a home-brew), which act as a central nervous system stimulant by increasing heart rate and blood pressure. This effect is most strongly noted in horses, and the effect appears to subside after 30 minutes (although, it's hard to ask a horse how they're feeling and understand the resulting "speech"). Again, probably a good reason to keep this plant away from small children and pets.
Saturday, July 28, 2012
Species name: Pontederia cordata
Common name: pickerelweed
This species of aquatic plant is native from southeastern Canada (Ontario, Quebec, New Brunswick, Nova Scotia) all the way south to southern Argentina in South America. There have been arguments by plant taxonomists in the past about whether the South American populations should be considered the same species as the North American populations, and so many Latin synonyms have been given to this plant in the past. DNA sequencing has shown that this plant is the same species throughout its entire range, but with small divergent sub-populations. These sub-populations may one day become their own species with enough time to genetically diverge from the parent population, but this has not occurred yet (since all sub-populations can still breed with their parent population). Due to land use change throughout much of the native North/South American range of this species, the chances of these sub-populations having enough time to genetically diverge from the parent population to produce distinct species is pretty slim. In fact, back yard garden ponds are some of the richest sources of this plant, with it escaping back into boggy and swampy areas if left unattended (it is a very vigorous seed producer!). Again unfortunately, it is not a very good competitor with invasive species (which we have many, many invasive species in North American wetlands) so it rarely establishes a new population for long.
Since this species of plant can grow submerged in water like rice can, it, like rice, requires some sort of mechanism in its tissues to be able to transport gas from where it is absorbed in the leaves to where it is needed for growth in the roots. To do this, the plant forms a special type of tissue called "aerenchyma," which looks a bit like empty honeycomb. The large, empty cells are used to store oxygen and carbon dioxide so the plant doesn't suffocate under water. A neat adaptation! The flowers also have a special adaptation to attract bees that you can see in the third picture, that yellow dot on the top petal. Once the flowers are pollinated by bees, the plant undergoes a process called "geotaxis," which refers to the entire inflorescence stalk bending to submerge the developing seeds under water (peanut plants also do this with their developing seeds; this is why peanut shells always have a bit of dirt left on the outside!). The seeds then finish maturing and are released into the muck at the bottom of the pond. This is also a pretty incredible adaptation; without a prolonged exposure to water, the seeds cannot germinate.
With the exception of ornamental value, there is no other major use of this plant by humans.
Friday, July 27, 2012
Species name: Miscanthus sinensis
Common name: zebra grass
I mentioned in a previous blog post about the tufted hair-grass, Deschampsia cespitosa, that there was essentially only a couple other very easily identifiable grasses without the use of a microscope, and this is one of them! Zebra grass is a grass species native to Asia that has the potential to become incredibly invasive in North America. Thankfully, there are many modern cultivars that do not produce viable seed, so this possibility has been reduced. The plant can still reproduce asexually through the use of rhizomes, but this mostly helps to "fill out" a patch, as opposed to spreading underground to a new location. That being said, I have seen some zebra grass in roadside ditches around southwestern Ontario (with the striped foliage, it's hard to miss!), so some has still very clearly (and very successfully) escaped. With a little background knowledge about this plant before you landscape with it, the chances of zebra grass escaping and becoming an invasive species is slim. This is definitely one plant where gardener responsibility is key: if you remove the plant from your back yard make sure you dispose of it properly, and make sure you plant a hybrid cultivar.
Other than ornamental value, it currently has no other uses. It is, however, being examined as a possible candidate for bioenergy (either through fermentation of the leaves to produce ethanol or burning the plants to produce combustion energy) due to the fact that it is extremely fast-growing during the growing season. It would rival sugarcane as an energy source (sugarcane currently accounts for up to 80% of Brazil's energy production annually in some areas, up to 50% of the energy produced for large cities. The Olympics in 2016 will run exclusively on sugarcane!) for temperate areas where it thrives. It also is not as destructive on an ecosystem like corn (so an attractive alternative for corn-based ethanol) and has much higher levels of genetic variation than typical crops so you don't have to worry as much about pathogens wiping out the entire crop in a growing season.
A word of caution about this grass: while it might not seem that way at first, the edges of the grass have saw-like projections which can seriously harm human skin if grabbed the wrong way. I was weeding in the garden and found this out the hard way. If you've got this grass easily accessible to a small child, make sure you put a fence around it until the child is no longer tempted to grab at the attractive leaves. If not, you might end up being the single reason why Band-Aid is still in business!
Thursday, July 26, 2012
Species name: Monarda media
Common name: purple bergamot
This species of plant is a common garden plant (especially in areas of gardens that are planted to attract pollinators and hummingbirds) but now relatively uncommon in the wild. The USDA lists the plant as "apparently secure" since it doesn't have much data on the population status of the plant, but whenever someone goes out looking for it they find it. In order for it to be listed as "secure" the population numbers have to be reasonably estimated and shown that based on current numbers and current threats, the population is at no risk of depletion due to regeneration rate. The next step up from this is obviously "secure, invasive" which means it not only regenerates itself faster than natural death/predation, but it is also a better competitor than the plants in its surrounding area. Purple bergamot is native to Ontario, and it is often mistaken for one of two of its close relatives: Monarda didyma (beebalm) or Monarda fistulosa (wild bergamot). Beebalm is traditionally a much more vivid red when it flowers than purple bergamot (which, to me at least, isn't truly purple--more like a "slightly more purple than red" pink), and wild bergamot has pale purple flowers. That being said, the flower colour of any one of these species can vary based on environmental conditions before flowering, so an overlapping range of colour possibilities between these three species can be expected, only furthering the confusion for which species is which.
All three of these species are very important in Native American medicine, especially for the Blackfoot, Ojibwa, Winnebago and Menominee people. They recognized the strong antiseptic properties of this plant very early on in human history, and have been using it as an antibacterial salve for many, many generations. Gingivitis and toothache caused by cavities were also treated using this plant; instead of grinding the leaves and using them as a paste, the herbal medicine was consumed as a tea. In fact, when you buy mouthwash you're using this same ancient herbal remedy: the modern source of the antibacterial chemical Thymol is still beebalm. These three plants have also been used to treat flatulence, headache, nausea, vomiting, and diarrhea. What can't this plant do?! It was also used by Native North Americans and Europeans to season wild game; the flavour of the plant is almost a mixture between mint and oregano.
A word of caution: the plant has reported stimulant properties, so making sure small children don't consume this plant is probably a good idea. I haven't specifically heard of any ill-effects of animals eating the plant, but I think the scent is deterrent enough for most animals. These are one of the few plants in our garden that is not consumed when still young by the combination of rabbits, skunks, raccoons, squirrels, chipmunks and groundhogs.
Wednesday, July 25, 2012
Species name: Hydrangea macrophylla
Common name: Bigleaf hydrangea, hortensia
This species of Hydrangea (there are somewhere between 70 and 75 species depending on which authority you consult; even DNA evidence gives two different stories depending on which gene is used to determine species limits) is native to Japan, and there are over 15 common cultivars (over 600 named cultivars in total, although many of these are not common outside of Japan) used in landscaping.
The most unique aspect of this plant (and one of the reasons why it is so widely planted outside of Japan) is the variable flower colour depending on which pH the soil is. It's not the pH directly that contributes to flower colour; it's actually the ability for the plant to take up aluminum ions. There are pigments in the flowers that automatically produce a deep pink or magenta (in some plants this can even be red), regardless of availability of aluminum. If this pigment is not present (and in some cultivars, mutations have been bred into the plant that prevent this pigment from being made), the flowers will be white. At lower pH in the soil, aluminum is more available for the plant to take up into its tissues. When aluminum and the pigment are both present in the petals of the flower, the flower will take on a blue colour. The intensity of this colour is directly proportional to the availability of aluminum to associate with the pigment; the lower the soil pH, the bluer the flower will be. The reverse can be said about higher pH: the higher the soil pH the less available aluminum will be to the plant, and so the pinker the flower colour will be. Towards the middle of the range, around pH 7.0, there is an equal availability of regular non-associated pink pigment, and aluminum-associated blue pigment so the flower appears purple. This concept of "litmus colour change" (where the idea for the litmus paper came from) is backwards from what you would usually think; usually red is a strong acid and blue is a strong base. That's one of the great things about chemistry! Depending on what causes the colour change, the same colour can mean different things under different chemical conditions.
All parts of the Hydrangea macrophylla plant contain trace amounts of cyanogenic glycosides, so consumption of this plant should be done with extreme caution. I would advise against all consumption, but many Asian countries use this plant as a medicinal herb. In Japan it is used to make a tea that is consumed at all times of the year, but in very high amounts around April 8th when it is believed to be Buddha's birthday. In Korea and China, the leaves are also used to make an herbal tea called sugukcha or ilsulcha.
Monday, July 23, 2012
Species name: Echinacea purpurea
Common name: purple coneflower
Since I spent so many days blogging about non-native daylilies, I figured I should start off the week on a good note by blogging about a native flower that is incredibly attractive in gardens and a good plant to use in gardens to attract bees, butterflies and moths: the purple coneflower. Interestingly enough, this plant is becoming less and less common in the wild due to land-use change, and potentially a changing climate. It thrives in dry areas in meadows or open woods, and is incredibly drought-tolerant once established. While not truly "deer-safe," once the stand of plants has established itself it is rarely consumed by large herbivores because of its prickly leaves and unpalatable, spiky flowers.
As many of you can probably guess from the name, this is a very popular medicinal plant. Historically, it was used very commonly in traditional native medicine in North America and has since crossed over into "main stream herbal medicine." People believe it has strong immune system boosting properties, and a couple of poorly-conducted studies have shown it has some effect on depression and L-DOPA (a potential treatment for Parkinson's). Unfortunately, none of these claims have been backed up by strong, repeatable scientific studies so the "true" medicinal effects of this plant should always be taken with a grain of salt. Taking an Echinacea pill or drinking Echinacea tea if you have a cold certainly won't harm you, but don't count on it making you better, either. Doesn't taste too bad with a bit of honey and lemon, and grows pretty commonly in gardens around the neighbourhood so it's a cheap treatment to try. Even the placebo effect alone might be enough to cure you of your cold!
The side effects of using this plant medicinally are incredibly rare, and usually include temporary rash or other form of skin irritation. There are a couple of documented cases of this plant causing a near-death allergic reaction, but these people also reported being allergic to sunflower seeds (so being allergic to this plant, too, shouldn't come as that big a surprise; they're in the same family). A word of caution regarding all plants that look like sunflowers or coneflowers: if you're using them medicinally or for food, make sure you know what kind of soil you're growing them in. Plants in the aster or sunflower family are referred to as "hyper-accumulators" of various toxic compounds including lead, cadmium, uranium, and copper, all of which can be toxic (copper is a compound required in trace amounts by our body for basic survival; in amounts too high toxicity and death can occur). Make sure if you "source" your Echinacea from a location other than your garden you know the history of the property (and the soil) to know if you should be concerned about heavy metal accumulation in the plant tissues.
Friday, July 20, 2012
Species name: Hemerocallis fulva
Common name: Orange daylily, tawny daylily, Tiger Lily (although this common name is misapplied)
Up until now, I've been profiling daylilies that are cultivars of the same species, Hemerocallis fulva. There are some cultivars that have been back-crossed with another species, but this is relatively rare. This one species of plant already contains all of the genetic variation (plant size, shape, flower size, colour, etc.) needed to produce all of the daylilies we've already seen. Also up until now, none of the previous cultivars profiled have the ability to successfully reproduce from seed (at least, quite rarely) and don't produce extensive rhizome systems underground so have a relatively small chance of becoming invasive.
This species of daylily, the one from which most modern cultivars are derived, is one of the most invasive plants in disturbed areas in the northern half of North America. Unfortunately, a lot of people seem to be under the impression that they're native to this area, and actively propagate this plant in roadside ditches and meadow areas. It's unfortunate when an invasive species is so visually appealing to so many people! The other unfortunate part about this plant is its success at reproduction; unlike many modern cultivars of daylily, this species is incredibly successful at reproducing sexually from seed. It can also successfully reproduce asexually from rhizomes (for example, spreading along the fence in clumps as illustrated in my back yard) and from re-colonization from broken colonies. If you dig a clump of tawny daylily out of the ground, make sure you ensure there's no contact between the roots and the soil below the clump or else it will re-root itself before you can even blink. Fascinating, but not if you like that part of your garden (or lawn!) daylily-free. The tawny daylily is also an excellent competitor for resources with other herbaceous plants in the vicinity, so it will also completely wipe out plant diversity in the area in which you're growing it. Even other "weedy" species have no chance against this plant.
The tawny daylily can also be eaten, but there seems to be a significant difference in taste between this species and the one most commonly used as "golden needles," Hemerocallis lilioasphodelus.
Thursday, July 19, 2012
Species name: Hemerocallis sp. (Hemerocallis 'Magic Dawn')
Common name: daylily
This cultivar of daylily was first registered in 1955, so this certainly isn't a new cultivar by any stretch of the imagination! The petals of these flowers are bright purple-red when they first open, fading to an almost blood-red or maroon with age before setting seed. Depending on the source of the plant, the sepals may or may not have a light maroon area around the edges that is slightly more visible with age. The popularity of the Magic Dawn cultivar also comes with its growing conditions; it prefers dry conditions and thrives in high plant density areas.
For a more in-depth blog post about daylilies, please click HERE.
Wednesday, July 18, 2012
Species name: Hemerocallis sp. (Hemerocallis 'Afraid')
Common name: daylily
This cultivar of daylily was registered in 1985 and has been a popular short-statured late-bloomer since. The flowers are a salmon-pink that become darker with age (as opposed to fading with age, as in most daylily cultivars), don't have a visible eyespot, and have a yellow-green throat. One great quality of this cultivar is that it can live quite happily in full sun to full shade, and can survive drought-like conditions (which we're experiencing quite a bit in southwestern Ontario this summer) for an extended period of time. Like the last cultivar I highlighted, Classic Caper, the petals and sepals of these flowers are quite different; the petals have a ruffled edge that becomes slightly yellowed with age, and the sepals are much narrower and much less pigmented.
For a more in-depth blog post about daylilies, please click HERE.
Tuesday, July 17, 2012
Species name: Hemerocallis sp. (Hemerocallis 'Classic Caper')
Common name: daylily
This cultivar of daylily was first registered in 1982, and is the first example of something called an "eye" or an "eyespot". The maroon colouring in this daylily cultivar is only on the petals, and only on the upper surface. It doesn't extend down to where the petals join (the neck or the throat), so it makes the flower appear as if it has an eye in the middle. Eyes in daylilies at one time were thought to be very difficult to achieve, but now they're becoming more and more common in modern cultivars. Perhaps all we as humans needed to do was find a cultivar that expressed the gene (or gene mutation), and the rest comes easily after that. Or perhaps it was just bad luck historically that led to fewer cultivars with eyes. As an aside, I have no idea how this cultivar got its name since the flowers of the caper plant are not anything remotely like these flowers (not in colour, pattern of colour or shape), and the fruit are picked green and pickled; the only thing I can figure is that it's named after the Latin grammarian Flavius Caper.
For a more in-depth blog post about daylilies, please click HERE.
Monday, July 16, 2012
Species name: Hemerocallis sp. (Hemerocallis 'Salmon Sheen')
Common name: daylily
This cultivar of daylily was first registered all the way back in 1950, and can almost be considered an "heirloom" cultivar. There are different requirements for what cultivars or varieties of plants can be considered heirloom based on the species, but in general it means that very little genetic modification (either modern methods or good old fashioned selective breeding) has been done to the plant. This particular cultivar looks a whole lot like Hemerocallis fulva in its "pure" form (which I guess now is a bit up for debate considering how much we've changed its appearance as humans) with just a bit more colour added in on the sepals and petals. This cultivar is reblooming if cut back after the first display of flowers, and the flowers also open leading up to the nighttime hours, with the blooms often looking a little worse for wear by morning.
For a more in-depth blog post about daylilies, please click HERE.
Saturday, July 14, 2012
Species name: Hemerocallis sp. (Hemerocallis 'Lucky Seven')
Common name: daylily
This cultivar of daylily is relatively common in North America, but losing popularity because of it's thin tepals compared to other species. It's not quite a "spider" cultivar, and not quite a "full" cultivar. I'm not sure if a cultivar that's somewhere between a spider variety and a regular cultivar has its own name or whether it's just considered partway between the two. To be considered a full spider cultivar, the tepals (sepals and petals) must be fully separate all the way down to the throat, where they join into the tube of the flower. I've never truly seen a spider cultivar, so they must be relatively rare, at least as far as Southwestern Ontario goes. The cultivar 'Lucky Seven' was first made in 1984, so I guess I should consider it one of my birthday cultivars!
For a more in-depth blog about daylilies, please click HERE.