Saturday, June 30, 2012

The unknown Draba

Species name: Draba sp.

Common name: whitlow-grasses

Location: Ontario

This is a prime example of "stump the botanist". First, I didn't take great pictures of this plant (I'll be the first to admit it!). Second, it's not in full flower anymore so I can't go back and take better ones. Third, I managed to narrow it down to a genus of plants with over 400 species. Fourth, mustards are notoriously difficult to identify when they're "non-native, yellow-flowered, small-ish plants with ovate leaves." If anyone has a suggestion to species names, I'm all for hearing them. The best I've got is something like Draba crassifolia or Draba graminea.

So what's notable about these plants? Well, they're all in the mustard family which is actually an enormous family of plants, all with small yellow or white flowers that have four petals. The non-showy species are native to North America, Asia and Europe, and the showy species with either larger or brighter-coloured flowers are native to Central and South America. I can say with pretty good confidence that this species is non-native, since our two most common native Draba species have white flowers. Out of the 400+ species in the genus, many of them are endemic to very small pockets in the world, with a significant number (30-ish) of those being found only in Ecuador. There are also 3 or 4 species that are endemic to locations in the Colorado mountains in the southwestern United States. All of these endemic species are at a very real risk of going extinct since their population numbers are so small.

This group of plants is also somewhat closely related to rapeseed, also called Canola in Canada (which is actually an acronym; it stands for Canada Oil Low Acid), which is an immensely important oil crop in the Prairie Provinces. Every time you eat canola-based margarine you're eating a genetically modified crop! Wild rapeseed is incredibly bitter and if you consume enough of the extracted oil it can burn the inside of your mouth and digestive tract. It was modified through selective breeding and modern biotechnological methods to lower the acid content in the seeds so it is a more practical source of edible oil.

Friday, June 29, 2012

The flower of Chinese Warriors

Species name: Paeonia lactiflora

Common name: Chinese peony, common garden peony

Location: Ontario

Based on the common name of this species, you can probably guess where the plant is native! Surprisingly enough, there are somewhere between 25 and 40 species of peonies (even DNA sequencing can't seem to pin down species limits, with different genes sequenced giving different pictures of how species are related and which ones are actually distinct species). There has been such an intense effort in cultivating "prettier" versions of this plant (mainly by the Chinese, Japanese and Koreans) that there are more cultivars of peony than almost every other ornamental plant; the only exception would be roses. Every year in China, Japan and Korea there are peony festivals in the spring when the plants bloom, and competitions for gardeners who can grow the prettiest flowers in various categories. There are also prizes given out for best new cultivars, so if you want a new and exciting peony for your garden that your neighbours don't have, those would be the places to go find them! When I was in Japan in May of 2006, the flower festival had just started and the peonies were in full bloom--and protected from the sun by umbrellas! It was one of the strangest things I had ever seen.

Most wild peonies, like most wild roses, look nothing like their cultivated relatives even within the same species. Humans have selected for detrimental mutants where the stamens (the part of the flower that usually produces pollen) have been modified into extra petals (and thus the plant can no longer reproduce). This is called "doubling" the flower, and you end up with the final result of having what appears to be thousands of petals inside the flower when there should actually only be about twelve. A aesthetically pleasing result, but not one that the plant would prefer! In fact, modern cultivars of peonies are completely dependent on humans for survival and propagation since they can no longer do it themselves. Some gardeners refer to that as the way that plants have domesticated us! We gladly help these plants out in any way we can: weeding around them to remove competitors, spraying them when they get a disease to make them healthy again, and trimming them back in the fall since only the new growth produces flowers. Humans are pretty easily manipulated by ornamental and agricultural plants!

Peonies are unusual in that they require grazing by ants in order for their flowers to open. Yes, those hundreds of pesky ants all over your flower buds actually serve a purpose! Don't go sweeping all of them off! The unopened flower buds produce a sweet nectar all along the outside of the outermost petals, and the ants walk along the petals and eat the nectar. By consuming the "glue" that holds the flower buds together, it allows the buds to spring open once enough of the nectar is gone. Why would a plant bother with this elaborate process for flower opening? Well, if there are ants around there are probably other insects around, too, which means the peony flower will be pollinated once open. A neat insect-plant mutualism.

Peonies have been valued, especially by the Chinese, for centuries not only as ornamental plants but also medicinally. Chinese art is often filled with peony flowers and the peony actually became one of the many preferred tattoos of Chinese warriors. Medicinally, historically it was used as an anti-convulsant and now is being researched for its antioxidant, anticancer and antipathogenic qualities. It has been suggested that one of the extracts from the peony, paeonol, can be used to modulate immune system function to help speed the body's healing after cancer treatment. This research is still in the very early stages, so don't get exited and start to eat your peony plants! Another reason not to do that is that many cultivars contain high levels of phenols in the leaves that can cause skin and digestive tract irritation.

Thursday, June 28, 2012

An almost-native ornamental grass

Species name: Deschampsia cespitosa

Common name: tufted hair-grass

Location: Ontario

Here's one example of a plant where the difference between "native" and "naturalized" has been blurred over the years. Technically speaking, the tufted hair-grass is native to the western coast of North America but it had been transported to the eastern coast centuries ago. It is now naturalized to a very similar habitat on the eastern coast; so much so that it's difficult to distinguish it there from a native grass because it thrives in communities with other native eastern grasses. In fact, this plant does incredibly poorly when planted on its own so there's definitely some sort of synergistic effect when it exists in grasslands. The idea is that in pure culture (that is, when the plant is growing on its own away from other native grasses) it doesn't possess the full community of symbiotic fungi in the root system of the plant that it requires, and so can't acquire nutrients as well as it can when grown in a grassland community. An interesting idea, but I'm not honestly sure if anyone has looked at this phenomenon with this particular plant in detail. And like animals, every plant is different! Reasoning for a lack of optimal growth in one plant species can't always be applied to another species even in the same habitat. Currently, the tufted hair-grass is not at immediate risk for population decline, however the habitat that it thrives in is becoming encroached by urban sprawl. There might be a time in the very near future that this is a species that's threatened or at risk.

In general, I really don't like trying to identify grasses since you almost always need a complicated identification key and a microscope. There are a few exceptions that I'll highlight later this summer, but this is one of the exceptions of the smaller ornamental garden grasses. If you run your fingers along the blades of grass of this species, one direction will feel like you're being cut by thousands of little razor blades (trust me, it's not pleasant!) while running your fingers the other way will feel smooth as silk. If the blade of grass feels that way and it has big tall seed heads that turn brown before the grass does AND you're in North America, then you've got the tufted hair-grass.

Interesting factoid: a closely related species to this grass, Deschampsia antarctica, is one of only two flowering plants on all of Antarctica!

Wednesday, June 27, 2012

The oak of champions

Species name: Quercus rubra

Common name: Red oak, champion oak

Location: Ontario

The red oak, who's "official" common name is actually the Northern Red Oak, is native to North America, specifically the northeastern United States and southeastern Canada. It is a popular ornamental and lumber tree worldwide, and has been spread across Europe and Asia. It's also the state tree of New Jersey.

The pictures I selected to showcase the red oak aren't exactly your typical tree pictures. We had three oak trees growing in the front yard: one angled slightly over the neighbour's driveway (they never park there anyway), one angled slightly over our driveway (it's just a car!), and one angled slightly over the house ('s just a house?). Since the one angled slightly over the house swayed more than just a little in the wind, it was decided that it would probably be best to cut it down. The top picture is what's left of "Curly" from our Three Stooges trees. Upon closer inspection (middle picture), the stump actually shows some pretty cool things about red oak trees! Even using a regular camera lens, you can actually see some of the cells that make up oak wood since they're so large. These cells are present in all trees, just larger in some than others, and are called vessels. Along with tracheids, they are the two types of cells that conduct water up the tree from the roots to the leaves. What most people don't know is that the only part of the tracheid and vessel system is still useful in a tree, and that's what's on the very outside of the tree. Trees actually grow by adding a new layer of wood to the outside of the tree, pushing the bark further outwards (which is why bark cracks and has ridges in it!). So that "old wive's tale" that you shouldn't carve your name into a tree because it might die? It's true! Injuring any part of the new growth of a tree leaves it open to infection even if there's still enough remaining wood for water transport.

Another neat thing that you can see from this tree stump is the ring pattern itself. Not all tree rings are created equal! In temperate areas, we always have trees with rings. Tree rings are created by the tree's generation of new tracheid cells. These tracheids are larger in the spring because there's lots of water and nutrients around, and smaller in the summer because of the lack of water. This makes a difference in density of the wood, creating what looks like stripes in the wood to our eyes but are actually just gradients of different sized cells. Red oaks are also what we call "ring porous," where all of the vessels are restricted to the spring wood, giving an even more distinct ringed appearance of the wood (which also gives a more pronounced grain when turned into furniture or flooring).

The last picture shows a phenomenon called "oak apple," which is the result of a parasitic wasp called the gall wasp laying eggs inside the plant tissue. This causes the plant to release wounding hormones at the site, which then causes tissue to be rebuilt. The gall wasp exploits this reaction by the larvae injecting these hormones continuously into the plant, causing the plant to make a bigger and bigger gall or apple. Once the larvae have matured, they bore a tunnel out of the gall, moult on the gall surface into the adult form, and fly away. In general, oak gall won't kill or otherwise harm the tree except in localized areas. If you're planning on growing a "show tree," the oak apples themselves are not very sightly. But if you do happen to have them, you should be thankful! Oak apples are one of the sources of a reddish-brown pigment used as ink ever since the Middle Ages, and they're actually the main source of ink for some of the oldest, most important texts of modern times. Now you know!

Tuesday, June 26, 2012

The Cranberry's long lost cousin

Species name: Cotoneaster apiculatus

Common name: Cranberry cotoneaster

Location: Ontario

Bonus points go out to anyone that remembers the name of the plant in the top photo with the small purple flowers. I'll give you some hints: the flowers have five petals with dark spots near the base of the petal, the leaves are skinny and not very long on the stems, and the plant is native to North America. Think you know what it is? Click HERE to find out.

This species of shrub is native to Western China, and is incredibly slow-growing. Most gardeners love this plant for its evergreen foliage, pink flowers in the spring that attract bees and butterflies, and the red berries (that look like cranberries, hence the common name) that attract bees in the early to late fall. The lack of maintenance required by the plant is also a plus! A word of caution, however: once this shrub is established, it is incredibly difficult to remove from where you don't want it because of the rooting stems. Because of its slow growing habit, it is unlikely to become invasive.

Other than the ornamental use (this particular plant is a cultivar that has been bred to be even more slow growing and more of an upright growth pattern), this plant has no other economic or medicinal use.

Monday, June 25, 2012

New blog colours

I figured since now it's officially summer in North America, I could change up the blog colour scheme to reflect the green of summer. Bring on the warm weather! :)

Trees make good wine!

Species name: Tilia cordata

Common name: Littleleaf linden, small-leaved lime

Location: Ontario

While this species of tree is incredibly common in Ontario (and much of the rest of Canada and the United States), it is not a native species. It is originally from Europe and Asia, but has existed as an ornamental and lumber tree in North America for over a century. This species of tree is well on its way to being considered "naturalized" in North America, which means it's a non-native species but it has been here long enough that a separate genetic pool exists in the North American population, the tree population is well established, is replacing itself through generations, and does not out-compete other native species for resources. These aren't the "rules" for determining if a species has been naturalized or not, but they can be considered general guidelines.

Linden trees, while very popular ornamental species due to their multi-coloured foliage during the spring, actually were more popular in Europe to grow as a medicinal tree than a purely ornamental tree. The lime green "leaves" that the flowers are attached to are called bracts, and act as protection to the flower during early development. The flowers themselves are picked and steeped in hot water to make a medicinal tea which people in many European and South American countries claim to have anti-inflammatory benefits and is used to treat colds, flu, sore throat, bronchitis and fever. Argentinians recently have taken this to a whole new level, infusing fermenting grape juice with Tilia flowers during the winemaking process to give the wine a flowery, light taste. I doubt the wine has any medicinal qualities to it, but it sure is good! The Tilia Torrontes is by far the best wine I've ever had. If you're interesting in trying a new wine (they also have a Tilia Merlot, Chardonnay, Malbec, Cabernet Sauvignon, Bonarda, and various combinations of the above), you can find the TILIA Wines website HERE.

The littleleaf linden is the national tree of Czech Republic and the Slovak Republic, of huge cultural importance in Sarajevo (the capital city of Bosnia and Herzegovina), a protected species in Ukraine and the all countries that are part of the former Yugoslavia, and considered a species at risk in Great Britain (it is considered an indicator species of an ancient woodland, which are becoming more and more rare in Britain with forest clearcutting to make way for agriculture and urban expansion).

Thursday, June 21, 2012

The many faces of Cannabis

Species name: Cannabis sativa

Common name: Marijuana, hemp

Location: Ontario

I should probably start this blog entry with a disclaimer: please note that those pictures do NOT have a watermark on them; I did not take them. A friend went to go visit their friend (who lives on a farm) and they discovered that someone had planted some Cannabis plants in the middle of their corn field. My friend took some photos, then contacted the authorities who dealt with the "situation." Now that we have that out of the way, let's carry on.

Cannabis plants have been in cultivation and in use by humans for more than 5,000 years. Believe it or not, it's actually one of the first domesticated plants! It originated in Asia, where there are currently two species of Cannabis that commonly grow. This species, Cannabis sativa, that has its origins in China and Cannabis indica which has its origins in India and Pakistan. The third species, Cannabis ruderalis, has murky origins; there's a group that argue the plant originated in Asia, but others that argue it has its origins in North America (the midwestern United States). Each one of these species has a different chemical composition of the "active ingredient," delta-9-THC. Since each of these species can hybridize with the other two (which would suggest they aren't distinct species at all according to some authorities), plant breeders often hybridize plants in order to increase THC content, decrease THC content, or add desirable plant characteristics from one species to another (for example, cold tolerance, drought tolerance or the ability to grow in a lower nutrient pH for hydroponic plants).

Contrary to popular belief, Cannabis isn't "just" the recreational drug marijuana. A common theme to almost every mind-altering substance (coffee, tea, chocolate, marijuana, opium, cocaine, etc.) is that the local people who domesticated the plant believe it was put on Earth as a gift from their respective God and that it should be used to its greatest potential. Cannabis is certainly no exception in that respect. Ancient Indians believed that this was a plant of the gods because it fulfilled every requirement for basic sustenance of life: parts of the plant can be eaten (the seeds are incredibly nutritious), the stems can be used for fibres to make clothing, canvas or ropes (why hemp became a popular plant in World War II), the extra plant material from the stems can be burned as fuel, and the leaves and flowers can be smoked to bring a sense of calm and reflection. Since then, low-THC cultivars have become very popular in Canada as a source of "green fibre": Cannabis requires less water than cotton to grow, less fertilizers and pesticides, no weeding, and grows at much, much higher densities. On top of that, Cannabis fibres can be softened to make heavy clothing like jeans just as soft as if they were made from a cotton plant. The major drawback to hemp as a cultivated crop is the number of government regulations surrounding its cultivation. A farmer in Canada wanting to grow hemp (to my knowledge, it's still illegal in the United States) must apply for a permit and agree to "spontaneous" spot-checks (which, to my understanding, occur weekly) of their fields. Government officials confiscate plants from different areas in the field and test their THC content. If they contain more than 0.9% THC, then the whole field is burned (recreational marijuana plants contain THC concentrations as high as 30% depending on the variety). The actual cultivation of these plants is also tightly regulated; a government official must be on site to witness the cultivation and processing of the plants to ensure that all of them are going towards their intended fibre, fuel or food use (hemp seed is a popular omega-fatty acid food additive). The question many people still have is: why? There would be no benefit to a farmer planting marijuana plants in the middle of a hemp field. They're the same species, and there is no way to tell the plants apart. Since they grow at such high densities, it would be impossible for someone to pick them out in a field. They show the same heat signature, so even flying over at night with an IR camera (as is often performed in Ontario where outdoor grow ops in corn fields are common) would show no difference. What incentive a hemp farmer would have to try to grow marijuana is something no one has quite figured out!

There are a huge number of reported medical uses of the Cannabis plant, but very few of these have been tested in any sense. Anecdotal evidence can sometimes be good evidence, but when it comes to an illegal drug (whether it should or shouldn't be illegal is a whole other debate, and one I'm not prepared to get into) anecdotal evidence can't be enough for prescribed use. So far, the only four conditions for which there is enough evidence to support prescribed purchase is cancer (smoking marijuana decreases the side effects of chemotherapy), glaucoma (helps relieve pressure in the eyes by fighting hypertension), asthma (THC helps dilate bronchi, allowing more air to flow into the lungs), and MS (reduces muscle rigidity and muscle spasms). There are clinical trials either proposed or underway about THC's effectiveness in the treatment of breast cancer specifically, the wasting effects of AIDS, the treatment of brain cancer, helping people wean off an opioid dependence, and the control of symptoms of ALS. There are also clinical trials underway to determine if smoking marijuana really does cause lung cancer (something that has been argued for many years; the confounding effect between pot smokers and lung cancer is that a great number of them are also cigarette smokers), and whether or not there is any effect of THC on mental illness (it has been argued that certain forms of mental illness can be aggravated through marijuana use; the addictive qualities of THC are also still being argued).

Tuesday, June 19, 2012

Bowling for Aquilegia

Species name: Aquilegia sp. (probably Aquilegia vulgaris)

Common name: Columbine (probably Common Columbine, European Columbine)

Location: Ontario

As you can probably tell by the proximity of the fence in the second picture (and the blurred plant in the background), this is not a species of plant in my back yard. I have to graciously thank my neighbours by allowing me to use their flowers as models (although they don't know it yet) and letting me steal flowers through the fence with elaborate stick mechanisms!

I honestly have no idea which species of Columbine this is. I'm guessing it's probably the common columbine since its English name is probably "common" for a reason. The common columbine has been selected for flower colour through hybridization by humans over many generations, so there are now cultivars with many different colours of flowers even though the "natural" colour of this flower is dark purple. Since I don't truly know which species this is, I can't also comment on the "nativeness" of this plant for certain, but since there are more species native to Asia and Europe than there are North America (but there are a few!), I'm going to pick the bigger group and go with non-native. There are about 65 species of columbines in the genus Aquilegia, and almost all of them are critically endangered (with the exception of the few species used for ornamental purposes; even some of those are endangered in their native habitat). We have 3 species that are native to Canada, and another 3 are native to the United States. One of these three American species is endemic to Colorado, where it only exists in one small pocket of the Sierra Nevada mountains, and is protected under federal law. Since it's also the state flower of Colorado, I wouldn't suggest taking your chances with American law enforcement and picking any flowers if you happen to stumble across them!

There is quite a bit of folklore associated with this plant because of the elaborate spurred flowers that are produced. At one point, even the Raelians (remember them?! If not, you can read about their philosophy HERE) believed that these flowers were too unusual to be a product of evolution and chance, and must have been created by their extraterrestrial God. The ancient Romans believed the columbine flowers to be the flower of Venus, and if you carried around a bouquet of columbines you would arouse the affection of a loved one. Going along with that, it was also used as an herbal medicine to relieve the pain of childbirth. In modern times, some herbalists use the rhizomes in a tea-like beverage as a diuretic or an astrigent; I would recommend you stay away from experimenting with this plant since some species can be a diuretic via kidney disintegration as opposed to increased kidney flow--and I don't think that's the effect you'd be going for!

Sunday, June 17, 2012

The Liver and Onions of the plant world

Species name: Marchantia polymorpha

Common name: common liverwort, umbrella liverwort

Location: Ontario

When it comes to ancient lineages of plants like liverworts, it's incredibly difficult to interpret "nativeness". The distribution of Marchantia polymorpha is worldwide in almost every habitat or ecosystem type around the world from the Arctic to the Antarctic, tropics to subtropics, and everywhere in between. There are two different life forms of this species, the male and the female plants. The second photo is a close-up of a cluster of female plants; the appendages on the umbrella of the female spore-bearing structures are much pointier than the male appendages. I have yet to actually see the Marchantia in the back yard produce a male spore-bearing structure. I'm not sure what determines what sex of umbrella is made when, but there seems to be a clear female-bias on this colony of liverwort. The other method of reproduction in the common liverwort is asexual through the production of structures called gemmae cups (pronounced like "jelly" only with m's in the middle). These structures are produced on the leafy part at the bottom that grows along the ground surface.

Liverworts have historically been considered part of a broad group of plants called the Bryophyta. This included the liverworts, hornworts and mosses; modern DNA sequencing has suggested that liverworts are actually their own ancient lineage, not more closely related to either mosses or hornworts (which are closely related to each other). All three of these types of plants are non-vascular plants, which means they don't have the ability to transport water and nutrients through their tissues. All three of these types of plants cover the ground or other substrate they live on (rocks, logs, soil, etc.) since they don't have the ability to transport nutrients higher than a few millimetres. Way back before the time of the dinosaurs the fossil record suggests that these plants, despite not having a way of transporting nutrients, achieved immense size, sometimes being as large as trees. Pretty incredible! How they managed that then and not now is probably simply a matter of competition: they were some of the first land plants, so they wouldn't have had many other plants around to compete with for nutrients and light resources. Now there are so many other plants around that they just can't compete anymore and stick close to the ground where they do best.

Saturday, June 16, 2012

Lacquered polypore

Species name: Ganoderma tsugae

Common name: Hemlock varnish shelf, lacquered polypore

Location: Ontario

This is probably as "native" as a species can get with respect to fungi; there is an Asian species of lacquered polypore that grows mostly on hardwoods, and this North American species that grows mostly on conifers, especially hemlocks. I took this photo when I was out with my supervisor at a private woodlot in Exeter, Ontario on an enormous hemlock stump of a tree that had likely been cut down in the mid-1800s to support the ever expanding railroad.

The two closely related species of lacquered polypore, Ganoderma tsugae and G. lucidum, both have reported medicinal properties (they have been used in Traditional Chinese Medicine for the last 2,000 years where the fungus is called "Lingzhi") while both fungi themselves are classified as "inedible" (since they have much the same texture as soft wood or hard cardboard, even after being cooked, and are not poisonous). The reported active chemicals in the lacquered polypores are called ganoderic acids, which closely resemble steroid hormones. There are many, many reported health benefits of these extracted acids, but whether any of these benefits are likely in terms of how much you can get from drinking a tea made from these species of Ganoderma is still up for debate. Among the reported benefits are anti-tumor effects, anti-inflammatory effects, inhibiting platelet aggregation, lowering blood pressure, lowering cholesterol, lowering blood glucose, and protection for the liver from viral infections like hepatitis. The traditional way to prepare the tea is to thinly slice fresh or dried fruiting body and to put it in boiling water where it will cook for two hours. The tea can be sweetened with sugar or flavoured with lemon juice (the tea is incredibly bitter) before consumption.

Friday, June 15, 2012

The railroad tree

Species name: Tsuga canadensis

Common name: Eastern hemlock

Location: Ontario

The Eastern Hemlock is a species of coniferous evergreen tree native to the east coast of North America (the Maritime provinces in Canada, and New England in the United States). This might seem obvious from its name, but I'll profile a plant in a later blog who's common name might sound like it's origins are in North America but they're really not. Most species of hemlock are native to Asia; there are only a few (3 out of the 9 or 10 species in the genus) that are native to North America, and only one native to Ontario (of the other two, one is native to the Carolinas in the United States, the other is native to the west coast of North America near Alaska and northern British Columbia).

Historically, the hemlock tree was very important in the lumber industry not for house building or furniture building materials, but for railway ties. Hemlocks are very slow growing trees, so it would take hundreds of years for a tree to be big enough to cut down to make one post. Trees were felled on the east coast, their bark cut off to make a square shaped log, and they were cut into pieces and shipped off to build the railways across North America. This was an incredibly destructive process, and there are still forests in the eastern half of Canada that have never recovered from this practice (the majority of which ended in the early 1900s when there were no more large Eastern hemlocks left). My PhD supervisor and I went out to a woodlot a couple of summers ago to look for mushrooms and it was one of the few remaining old growth forests that had once been dominated by hemlocks; there are still stumps left of enormous old trees that had been felled. The good thing about leaving all these stumps behind is that some really neat fungi grow on them!

Unfortunately, the Eastern hemlock is under severe threat of population destruction by an invasive pest from Asia (that usually attacks the Asian species of hemlock which are relatively resistant to the insect). The insect is called the hemlock wooly adelgid, and when it latches onto the tree it often gives it a blueish "furry" appearance at the base of the needles. The insects drink the sap from the tree and burrow under the bark, destroying the tree's ability to transport nutrients from the roots to the growing branches, or the photosynthesizing needles to the growing roots. This causes extreme plant stress, more often than not leading to death. The only way to get rid of these adelgids once they attack the tree is to cut the branches off, and any arborist will tell you that hemlocks are especially sensitive to pruning because they are so slow growing. Pruning the ends of branches is fine, but cutting entire branches off should only be done one or two per year to ensure tree survival, not half the tree. Since there is no real treatment for these insects once the infection has started, it can essentially be taken as the kiss of death for the tree, and it should be removed from the garden immediately to prevent the spread. The other aspect of plant removal that must be taken into account is that the tree can't just be mulched or composted! It should be removed from the area and burned to kill the insects and to prevent future infection.

Thursday, June 14, 2012

Artistic Ferns

Species name: Athyrium niponicum

Common name: Japanese Painted Fern

Location: Ontario

As you can probably guess from either the common name or the Latin name, this species of fern is native to Japan. This species has had the variegated pattern of colour on the leaves selected for over hundreds of generations, leading to three main cultivars: one with silvery-grey leaves with a bright red stem ('Pictum'), one with yellow leaves and a bright red stem ('Red Beauty'), and one with silver, green and red leaves ('Metallicum'). Based on those three choices, the morphological characters of the Painted Fern growing in my back yard are most consistent with the 'Pictum' variety, but I'm guessing it's a different cultivar altogether.

Ferns are a group of land plants that first evolved in the Devonian as plants colonized land, between 359 and 416 million years ago. They quickly dominated the landscape, some growing to be hundreds of feet tall and looking like modern trees. Unlike the trees of today, ferns do not reproduce by making seeds. Instead, they make spores (like fungi!) and display a form of life cycle called alternation of generations. Once spores land in an area with a suitable amount of nutrients, the spore germinates and can grow into a type of plant called a gametophyte. This part of the fern life cycle is very tiny; often not being more than a centimeter across. This gametophyte produces eggs and sperm, which combine to make a zygote. This zygote has the potential, if in an environment with enough resources, to grow into a sporophyte. This sporophyte is what we traditionally think of when we think of a fern, and is what is pictured in the photos above. The sporophyte produces spores, and the cycle continues.

Some species of fern are used as a food source, but this is not one of them. Painted ferns are only used as an ornamental plant.

Tuesday, June 12, 2012

The Climbing Hydrangea

Species name: Hydrangea petiolaris (also Hydrangea anomala)

Common name: Climbing hydrangea

Location: Ontario

Like many species of hydrangea, the climbing hydrangea is native to Japan, Korea and Siberia. It prefers moist, shaded, cool areas for growth, which is why it's such a successful plant in Canada as an ornamental despite our harsh winters. Unlike other species of hydrangea, climbing hydrangea inflorescences, or groups of flowers, don't have all the flowers in full bloom at the same time. Contrast this to the big-leaf hydrangea that produces enormous blue and pink flower heads throughout the summer (coming soon to a blog near you!).

Once again, I have to bring up the issue of taxonomy when it comes to naming plants, and different "rules" when it comes to plant names. Traditionally, there are three schools of thought when it comes to the proper name of this plant. Way way way back in the good old days (I'm talking early 1800s), this species of climbing hydrangea was treated as a completely different species as the climbing hydrangea that occurs in China, Myanmar and the Himalayas. That species, Hydrangea anomala, is slightly smaller in overall size and leaf size but other than that they're basically identical. After a generation or two of botanists, someone decided that actually, the "species" that occurs in Japan, while distinct, isn't a species at all. It's a subspecies of Hydrangea anomala (which was named first, so that name gets priority) and so the name was changed to Hydrangea anomala subsp. petiolaris. A few generations of botanists later, and now it's not even a subspecies, they're actually the same species and climatic differences explains morphological variation. Then comes along DNA sequencing...and we still can't seem to get it right. Depending on what website you consult, it's either a subspecies or its own species. That would imply that there are genetic differences between the two populations, but the question is how much is enough to be considered separate species. It seems like every time biologists start to agree on an answer to that question, there's a well known species or genus that is an exception to the rule and the rule has to be rewritten.

This plant is becoming more and more popular as an alternative climbing vine to English Ivy. It doesn't have the ability to anchor itself as strongly to its supports (which is an attractive quality if you think you might ever want to take it out later...good luck doing that with English Ivy!) so often needs a little "help" in that department. It also produces attractive flowers (unlike English's basically just a boring leafy plant) during the summer. One disadvantage is that it does lose its leaves during the winter, so it's as insulating during the colder months. But still a great garden plant!

If left to its own devices it would be locally invasive, as in it can completely smother out any plant within about 200 square meters from it (except the ever-thriving Madagascar periwinkle). I have yet to see any seedlings popping up in any other location in our garden, so it doesn't seem to be very successful in sexually reproducing from seed which means the chances of it becoming invasive on a larger scale is pretty slim.

Monday, June 11, 2012

The Nine of Barks

Species name: Physocarpus opulifolius

Common name: common ninebark

Location: Ontario

There are about ten species of ninebark shrubs, nine of which have their origins in various parts of North America. I figured that with my luck, the kind we had in our back yard would be the only one native to Asia. I'm pleasantly surprised! We have the good old common ninebark, native to eastern North America.

The common name of this plant comes from (literally) the shape of the bark when it peels. The bark peels off in strips as the plant matures, usually from the top down and curling as it goes. When a strip curls enough to make a loop, it looks roughly like the number nine. I guess I probably should have said "some imagination required"! This is a great ornamental species for gardens, especially along slopes. It is drought-tolerant, flood-tolerant, salt-tolerant, disease resistant (except for the foliage, which is actually incredibly sensitive to fungal growth when constantly moist; water this plant at the base, not with an aerial sprinkler), shade-tolerant, sun-tolerant, and able to live in just about any kind of soil conditions. Not bad for a native species! Ninebark shrubs are relatively slow growing, and usually won't flower if pruned regularly (which would be a bad thing if you like flowers; the flowers of this group are not very spectacular and they're grown more for their attractive foliage colours).

Aside from their obvious use as an ornamental plant, this species has no other uses of significance. Since they are a native species, some governments at various levels (most often State governments in the US) have started planting these shrubs along highways that are beside very steep inclines as erosion control.

Saturday, June 9, 2012

It's a creeper! It's a crawler! It's English Ivy!

Species name: Hedera helix

Common name: Common ivy, English ivy

Location: Ontario

As you can probably guess from the common name of this plant, its origins are in Europe (and also Asia). It's a somewhat unusual plant in that it is an evergreen species, which contributes to its invasive properties in that it can photosynthesize in the winter. This plant produces structures called rootlets along the stem, which help anchor the vine to any surface that's suitable. When there isn't a suitable surface, they act as regular roots by anchoring the plant into the ground and absorbing water and some nutrients. If you're really observant, you'll notice in the top two pics that English ivy and Madagascar periwinkle (that you can read all about in a previous blog post HERE) seem to be able to live together quite nicely, completely covering the ground with their vines (and that's a relatively high traffic area, too). Both plants must be flooding-tolerant, since that location in the back yard can get incredibly soggy during the spring melt and during the summer's intense rains. The ability of this plant to out-compete other plants is so impressive that English ivy often creates "ivy deserts" where it has strangled out all other plants and is all that exists on a landscape. This can be contrasted with the plant kudzu, which is an invasive vine in the United States that has choked out ground cover, shrubs and trees in Florida and Georgia (and is moving its way north).

John Gerard plays an important role in the historical uses of this plant, like Solomon's seal. He once advocated that soaking leaves in warm water would create a tonic that could be used to help eye soreness and dryness. I would absolutely not recommend this as a modern treatment for dry eyes (aside from the fact that you should never, EVER mess with "home treatments" when it comes to your sight) since English ivy can produce an intense allergic reaction upon contact with a chemical contained in the leaves called falcarinol. On the skin it produces contact dermatitis (a rash-like reaction), but in contact with the eyes it can induce blindness if you're sensitive to the chemical. Interestingly enough, most people with this sensitivity usually greatly dislike carrots since they also contain the same chemical and can produce an "itchy mouth" (I'm sure there's got to be a technical term for that...). Historically, the berries of this plant have also been used to treat bronchitis.