Myriad wetland plants

Mid to late summer is a great time to see a diversity of wetland plants. Many will have a prolonged flowering period due to fluctuations in moisture levels. The proximity to water also moderates the air temperature, which can prolong the flowering period.

Wetlands are generally hard to access without a kayak or canoe. Fortunately there are trails complete with observation platforms in some of the provincial parks and national wildlife areas of the region that provide excellent access and viewing opportunities.

This first photo is of the observation tower at Rondeau, and the photo that follows shows a marsh scene looking north from the tower.

 St, Clair National Wildlife Area, along the shoreline of Lake St. Clair, also has a trail and tower.

 A more basic, but still quite useful observation platform is present along the Angler Line to Mitchell's Bay trail.

 Any of the trails leading to these towers pass through wetland areas that are full of attractive plants, some of which are illustrated below.

Spotted Jewelweed (Impatiens capensis)

This Spotted Jewelweed, a.k.a. Touch-me-not, looks like a small horn-of-plenty. It gets its a.k.a. name because the seed pods, when ripe, will explode when touched, which is an interesting mechanism for seed dispersal.

Another species is the Fringed Loosestrife (Lysimachia ciliata) named because of the fringed edges of the long-stalked leaves.

Fringed Loosestrife

This next species is Giant Ragweed (Ambrosia trifida). It occurs in disturbed areas as well as along the edges of wetlands. It can be very tall, sometimes reaching 4-5 metres in height. Its greenish candelabra style of growth and branching reminds me of a book I had to read back in about Grade 10 English.....The Day of the Triffids, by John Wyndham. It was a sci-fi story about tall plants that could move on their own, and spit venom into people's eyes which caused blindness. The few illustrations in the book showed these weird plants having a distinct similarity in appearance to Giant Ragweed, too. At least that is what I recall....Grade 10 was a loooong time ago! And interestingly, the species part of the scientific name of Giant Ragweed is 'trifida' so I assume there must be some kind of connection, even if only in a sci-fi way. I think about that literary classic (?) often when I see this plant.

Giant Ragweed

In the dense vegetation along wetland trails, you may see this three-leaved plant twining around other types of vegetation. There will be a pea-type flower that is pale bluish white. It is known as Hog Peanut (Amphicarpa bracteata).

Hog Peanut

Often closely situated with Hog Peanut is Swamp Thistle (Cirsium muticum), a much taller plant. It looks like other thistles, except there are few spines on the mostly purplish stem. Also the flower heads often have many strands of spider silk present, more easily seen in the second photo.

Swamp Thistle

Boneset (Eupatorium perforatum) is another one often found close by, along with Spotted Joe-pye-weed (Eupatorium maculatum).

Boneset

Spotted Joe-pye-weed

Pokeweed (Phytolacca americana) may be found along shrubby wetland edges, as well as open woodland edges. It flowers progressively, with flowers, developing fruit and ripe fruit sometimes present on the same flower head. Although the dark purple berries look tasty, and in fact are popular with birds, they apparently are somewhat poisonous to humans, so leave them for the birds!

Pokeweed

Some plants are covered with white flowers. The one that follows is Wild Cucumber (Echinosystis lobata).

Wild Cucumber

Blue Vervain (Verbena hastata) is a less obvious species than most of the ones shown previously. It also blooms for a long period. Only a very few flowers are open at any one time, but there is a progression of them from bottom to top. In addition to wetland edges, it is found in wet prairies. Although the colour of this shows as purplish-pink, in reality is a little more blue. But for some reason photos of blue flowers typically show up with more pink than they actually have.

Blue Vervain

Once you get to where there is open or standing water, the vegetation changes a bit. The following photo is of Water-willow (Decodon verticillatus) a.k.a Swamp Loosestrife. It has arching stems. When they bend far enough to touch the water surface, the stems will expand via special cells that make them very spongy, and often roots will extend from these spongy cells.

Water-willow

 One of the rarer wetland plants in Canada is Swamp Rose Mallow (Hibiscus moscheutos), and is considered a Special Concern classified Species At Risk with a provincial ranking of S3. S3 means there are fewer than 80 known locations, and due to their habitat or other factors, are at risk of being extirpated. It is quite abundant in the wetlands along the Lake Erie and Lake St. Clair shorelines, but away from those areas it is almost non-existent. It apparently was recently found in a single wetland along eastern Lake Ontario, the only location on that lake. It is a large, showy plant and easily stands out amongst the cattails.

Swamp Rose Mallow

This latter image was taken from the observation platform along the Erieau Rail Trail, looking out towards the village of Erieau.

Another plant is Wild Rice (Zizania aquatica), also seen here from the Erieau Rail Trail platform.

Wild Rice is quite abundant in lakes of northwestern Ontario, but the southern Ontario variety has declined considerably and is ranked as S3. It is greatly affected by water levels. It seems to do best when the water levels are high in the spring, which suppresses some of the vegetation, but drops almost to the point of exposed mudflats by mid summer. If that happens, it can be the dominant vegetation. The large drainage ditch along Erieau Road just north of the McGeachy Pond area is quite full of Wild Rice. This particular photo shows only a single plant, but is easily identified by its height and form. Wild Rice is a favourite of wildlife. Ducks love it, and if you come across a dense stand in late August when Soras are migrating, toss a pebble into the stand during an evening visit and you may hear a chorus of peeps. I have done that in a very large stand of it and on occasion estimated there were at least 100 Soras peeping back at me.

An obvious wetland plant is Cattail (Typha sp.) I use the 'sp.' to indicate that it is difficult to tell sometimes whether the species most common in this area is Wide-leaved or Narrow-leaved Cattail, and they often hybridize to the point where it is almost impossible to tell for most of the season. When it is in peak flower, there are slight differences in the flowers, but those characters only occur for a short time. It is believed that most of the cattail vegetation in southwestern Ontario is the hybrid type. Of course the brown cattail is quite identifiable as Typha.

Cattail

And with that, I will close, but before I do, I want to wish all of the summer staff at the Rondeau Provincial Park Visitor Centre a sincere thank-you for all of your work this summer. Many of you will be pursuing your education goals beginning as early as next week. If you have time to read this before packing it in at Rondeau, I sincerely hope that the transition back to school goes well for you. And hopefully we will see you back at Rondeau in 2015!

Tallgrass prairies of Walpole, in their prime

I have been fascinated by prairie and savanna from at least as far back as 1973, when I was working at Rondeau. And since the 1980s, I have had the privilege to be able to explore some of the finest tallgrass prairie and oak savanna in Ontario, and arguably Canada. The prairies of the Walpole Island First Nation are indeed remarkable and spectacular. One of the prairie sites has, on more than one occasion, hosted a breeding pair of Henslow's Sparrows!

You may remember a previous post, in early July, where I was able to visit one of the more remote prairies at Walpole Island, along with the owner and her family. It looked like this:

I had memories of this site from a few years earlier, when it was in its peak of colour with the Dense Blazing-star in its prime, along with several other showy species, so we planned to re-visit in early August to again see it in that showy condition. On the way in, we saw various prairie flowers in their prime, including Flowering Spurge.

Flowering Spurge (Euphorbia corollata)

Grey-headed Coneflower was also doing well. It is provincially ranked as S3, meaning there are fewer than 80 locations for it in Ontario and is vulnerable to extirpation..

Gray-headed Coneflower (Ratibida pinnata)

As we got to the site we were headed for, we were not disappointed.

This image was taken from a very similar vantage point as the first one in this post, but at a slightly different angle.

Dense Blazing-star (Liatris spicata) is one of the prairie plant species which many consider to be iconic.....that is, when one sees it, it evokes a sense of place that is a high quality tallgrass prairie. Mind you it can grow in some rather disturbed sites as well, but in a setting such as the one above with a multitude of other quality prairie species, it truly is an indication of a special place. Dense Blazing-star is a Threatened species under the Endangered Species Act. Under the Provincial Ranking system, it is S3.

Purple is the primary colour, but if you look closely at the image preceding this, you may have noticed a white plant. It is a rare white colour form; less than one per cent of all blazing-star stems are white. It serves to add to the diversity of colour at this time of year when so many prairie plants are purple against a green background.

On the day of our visit, it was a wonderful day to see some butterflies as well. Monarchs, Red-spotted Purples and Black Swallowtails were fairly abundant, but the one that caught my eye was Giant Swallowtail. There were several flitting about, enjoying the nectar of the rich purples available to them in this setting. Giant Swallowtails are ranked as S2 in the provincial ranking system, meaning that there are likely fewer than 20 populations and have a restricted range in Ontario and are very vulnerable to extirpation.

In both of these cases, the swallowtails chose to sip on the flowers of an ironweed rather than the blazing-star and that seemed to be the case most of the time. I'm not sure if the deeper purple colour was more attractive, or maybe the nectar was more satisfying. I'm not a butterfly whisperer to know that detail.

There are two species of ironweed on the Ontario prairies. For many years it was believed there was just one species, but in the early 1990s while a botanical colleague and I were photographing some prairie plants on Walpole, he realized there was something different about some, and after a closer examination of images and confirming using technical manuals, I concurred, thus adding with some certainty that there was in fact another species. The differences are somewhat subtle, and are based in part on the number of florets (small, individual flowers on the flower head). One species is Tall Ironweed and the other is Missouri Ironweed. The next photo is of the latter, and most recently confirmed, species. It is provincially ranked as S3.

Missouri Ironweed (Vernonia missurica)

Of course tallgrass prairies are more than just colourful wildflowers, although they are the showier plants. But as the name 'tallgrass' suggests, grasses are a major component of such a prairie. A healthy prairie in the mid-west consists of about 70% grasses, although there are only a handful of species making up that ~70%. Here in the eastern range of the tallgrass prairie biome, it is believed that wildflowers, collectively called 'forbs', make up about 50% of the vegetation in a healthy prairie, and grasses the other 50%. This may be due in part to the greater amount of precipitation in the east. Prairie grasses in general have deeper root systems than most forb species, so that in the drier part of the prairie range in the mid-west, the grasses have the advantage over the forbs. It may also be partly due to the greater presence of savanna, those prairie-type habitats where up to 25% of the cover is made up of fire resistant trees, usually oak species. Some forbs that do well in an oak savanna will also do well in a tallgrass prairie.

Indian Grass (Sorghastrum nutans) is one of the main grasses to be found on a tallgrass prairie. Grasses have flowers too, although most people do not pay much attention to them. This particular plant was in good flower, with the bright yellow stamens visible here.

In this next photo, there are some tall grasses visible amongst the forbs, although more in the background. They are Big Bluestem (Andropogon gerardii), a.k.a. Turkeyfoot, named because of the 3-4 flower and seed spikes at the top that may resemble the foot of a turkey. It is by far the most abundant grass of most tallgrass prairies.

Also in this image is a Tall Sunflower (Helianthus gigantea) visible in the upper right. In a few days, this scene will have taken on a decidedly yellow look, as the many goldenrod species open up. There are some goldenrods in this image that are in a tight bud stage, but have not yet opened.

I will be posting more on Ontario's tallgrass prairies in the future!

Life and death in the back yard

Milkweeds are more plentiful this year, thanks to them being taken off the noxious weed list a few months ago. So Monarchs and other insects have greater nectaring sources than ever.

Common Milkweed

Not long ago, I watched a female Monarch laying eggs on one of several Common Milkweeds in our back yard. Notice the tip of her abdomen curled up against the underside of the leaf.

After she left for other milkweed leaves, I took a close look and this is what I found.....a single tiny egg.

It is a mere millimetre or so in diameter, so clearly another need for macro equipment! I watched this egg, and others, from time to time, expecting it to eventually hatch, and a few days later, this is what I saw.

 A close look reveals an exit hole at the lower left hand side of the egg. At first I thought it meant that the egg had hatched, and the tiny larva would be out feeding. However closer examination, and a bit of reading up on the process, led me to conclude that this egg had been predated. A normally hatched egg is slightly darker at the top. And the larva normally eats the egg casing before chewing a small hole in the milkweed leaf to gain access to the top. If you see a small hole in the leaf like this next photo, it could mean that an egg has hatched and the larva is out feeding.

 While I was photographing the empty egg in the photo above, I watched a small ant come along, and dive into the empty egg, presumably looking for remains of an egg, if not the entire contents.

This ant stuck around for several minutes, breaking into the already empty egg shell, before moving on to other sources of food.

Had the egg successfully hatched, a small caterpillar would have begun the next stage of its life's journey. Unlike some butterfly caterpillars, Monarch caterpillars remain essentially the same colour throughout the several instars (stages of growth) before forming a chrysalis.

This lower photo shows the caterpillar sharing the milkweed plant with quite a few aphids. These brightly coloured aphids are not native, but were introduced. They are very soft bodied and send their long mouth parts deep into the plant to access the sugar rich sap. Often they become so numerous that their sticky droppings give a shiny wet appearance to the leaves below.

If the caterpillar is successful, it will eventually form a chrysalis, or pupa, where it will spend approximately two weeks before emerging as a full adult. I have seen about 20 caterpillars on the milkweeds in our yard, but I have yet to see a chrysalis this year. Unless they are unable to do so, they will typically leave the milkweed plant and form the chrysalis elsewhere.

This is the hoped for end result of all that effort.

But as much as we would like to see a profusion of Monarch butterflies, nature doesn't allow it. Death comes to many of the eggs, as I described above, and larvae.

And death comes to many other small critters using the milkweed plants. The milkweed plants are not carnivorous like some bog dwelling plants are, but they are killers nonetheless. They attract lots of insects, some of them which are critical to successfully pollinate the milkweed flowers. But if you take a close look at the flowers of this plant, you may find something else.....dead insects.

The flower parts of the milkweed are tricky for some insects to manoeuvre on. The parts of the flower separate somewhat. If an insect is very light, they can walk across the flower parts without any trouble. If the insect is heavy, it will be able to pull its leg out from the 'horn' of the flower which may otherwise entrap the insect. If like in the story of Goldilocks and the Three Bears, if the weight of an insect is just right....or just wrong as far as the insect is concerned, then the insect may have one or more of its legs caught in the flower parts and not be able to free itself. This next photo shows a fly, which is dangling down and quite dead.

This next photo shows a slightly larger insect, a type of bee, which I was surprised to find entrapped.

I thought it was a goner as well, but it struggled and a couple of days later, I noticed that it was gone. Some insects may even get to the point of pulling the entrapped leg from its body in its struggles, but when you've got six legs and rely heavily on wings for transportation, I guess surviving with only five legs is a preferable option.

We noticed another deadly event in our back yard recently. With all of the vegetation, it is attractive to Eastern Cottontails. On more than one occasion, they have had nests in our yard, and the adults can be seen all year around somewhere in or near the vicinity of our yard. A couple of little bunnies have been hanging around nibbling away at various types of vegetation.....sometimes the clover in the yard, and sometimes the flowers.

There is no question that little bunnies are cute. But one day not long ago, Marie ventured out into the yard first thing, and saw this sight.

Clearly a bunny had now provided nourishment to a predator of some sort, with only a few clumps of fur and its entrails remaining. We suspect it was a cat, since they are great hunters and more than one happens to roam around the neighbourhood. A bird of prey such as a Great Horned Owl would likely have flown off with it, not wanting to hang around the yard any longer than necessary to capture its prey. Clearly whatever caught this ate it on the spot, and it was not afraid of spending time in a residential area. The gates around the yard were closed, so it wasn't likely a dog, although it is always possible it could have been a fox, which does have the ability to climb. But a cat is my guess.

It is a sad tale concerning the bunny, but nature isn't always pretty.....if it weren't for predators, given the rate that cottontails reproduce, we would be over run with them in very short order!

 

A highly endangered native orchid

One of the highlights of my season, is to check on one of the rarest orchids in Canada. It is so rare, that it was first discovered in a privately owned woodlot in Essex County as recently as 1950, and a few years later was noted in Rondeau Provincial Park. In spite of periodic monitoring, the Essex County population may no longer exist, resulting in the only Canadian population being at Rondeau.

The orchid I am referring to is a tiny, diminutive and difficult-to-see native species with the common name of Nodding Pogonia, a.k.a. Three-bird's Orchid  and a scientific name of Triphora trianthophora. And this is what it looks like up close.....real close.

Nodding Pogonia

It is quite a pretty little thing, with the emphasis on little, especially if you find one that has that magenta tinge to the petals. Most specimens are white, but I am always attracted to the magenta ones when I can find them. Some years there are hardly any magenta ones with predominantly white ones being all there is to see, such as this next one.

I have had the privilege of following this plant population ever since 1973, when it was first pointed out to me by my naturalist colleagues during the first summer I was on the seasonal naturalist staff at the park. The numbers have fluctuated greatly over the decades, perhaps partly because it is so tiny and difficult to see especially when it isn't in flower, which is most of the time. During one of the best years for it in the mid 1980s, I counted more than 1400 plants, which was amazing. The 2008 year was probably the second best year I have noted. The poorest year was in 2012 when, although I found a couple of dozen plants, absolutely none produced open flowers and therefore none produced seed. I have had study plots set up for this population ever since 1986 and have monitored the population almost annually.

Look at the next image.

Make the image as large as you can, and count how many Nodding Pogonia plants you can see. Do you see any at all? This photo was taken with a standard focal length lens, from only a couple of feet away, which is a lot closer than you would normally be viewing the ground flora at. This is what the plant looks like most of the time, for reasons I will explain shortly. In actuality, there are about 15 plants in this cluster!

Did I say that this plant is little? The average height of this plant is no more than 12 cm, or about 4.5". The flower itself, when fully open, is typically less than about 2 cm high. There are usually only one or two small, roundish leaves, each of which is less than 1 cm in diameter. Clearly macro photography equipment is required for this diminutive denizen of the Rondeau forest!

It puts out, in a good year and if it is a healthy plant, about three flowers over the course of the season (hence the Triphora trianthophora, the latter epithet meaning three flowered). The greatest number of flowers I have ever seen on a single plant over the course of the season was 7. Many flowers only put out one or two, and it is surprising how many grow but do not put out any flowers at all! The next photo - one of my favourites -  shows a very rare occurrence, with three flowers on the same plant being open at the same time. And a magenta one at that! This was taken in August of 2008, the most recent year when there was a fabulous showing of the species at Rondeau and included a few magenta ones to choose from.

The earliest I have ever seen a flower was on July 31, and the latest I have seen one is about September 20. However the peak of flowering is about the third week of August.

A bit earlier I mentioned that the plant is in a non-flowering condition for most of the time. It has a very curious flowering strategy. The plants will develop flower buds at their own pace, but will not open right away. Instead they will remain unopened, waiting for an environmental trigger. When there is a significant drop in night-time temperature, then usually on the morning of the second day to follow, all of the flower buds that are at a certain stage of readiness, will open. They will remain open for only a day (or less if they are pollinated sooner), then close up. If they are pollinated, then seed development begins, but if they are not pollinated, they will dry up and that is the end of it......there are no second chances!

The next set of buds will develop, and after a similar weather related trigger, will open several days after the first set opened. Often that is at least a week later, but it all depends on the weather.....those cool August nights are highly beneficial to this species. The benefit to this flowering strategy is that since the plants are not plentiful, if they are all open at the same time, they are more likely to attract pollinators and be successfully cross-pollinated. Of course it begs the question: why don't the flowers remain open for more than a day, as most other plants do? This would increase the rate of pollination, one would think. I haven't come across any explanation for this one-day flowering, so as far as I know, it remains a biological mystery.

This next photo shows a nice magenta flower in peak condition. There is another flower bud (the lowest one) that opened a few days before, and another developing flower bud that will hopefully open in another few days.

The plants may be scattered singly or in clusters. Here is what a small cluster may look like when opened. This photo was taken with a 100 mm macro lens, from a distance of about 2 feet. They are certainly more visible here than in the third image of this post. But in the dappled light of the forest floor, even when they are in flower they can be next to impossible to see. They are very small!

Some other interesting aspects of this tiny orchid include:
-they don't have roots like many other plants. Instead they have a tuberous root that is situated between the leafy humus layer and the sandy soil. They have a very close association with mycorrhizal fungi, which is established in the leaf mould, from where they get some of their nutrients.
-the main pollinators are small bees of the Halictidae family.
-adequate moisture well before the growing season is highly important to support the mycorrhizal fungi as well as the plants themselves. In dry years, as it was in 2012, flowering is greatly diminished or even non-existent.
-these plants can be dormant for quite a few years. Even in the heart of their range, in the southeastern US, colonies or at least parts of the population can be dormant for several years at a time. More than one population which was believed to be gone, has re-appeared.
-after a flower has been open, it droops (hence the Nodding aspect of its name). If it has been pollinated, the seeds develop, and when the seeds are ripe, the seed capsule will extend straight up. Eventually the capsule will split at several points, allowing the extremely tiny seeds to escape and be carried away by even the gentlest breezes. If the seeds land on a suitable substrate, a new plant may begin.

Now that I have you all excited about this plant, I have some unfortunate news. You probably won't get a chance to see it.

Due to its extremely limited occurrence in Canada, its extremely erratic flowering behaviour, its diminutive stature (did I say it was very tiny?), and the strong likelihood that even careful visitors could inadvertently trample it, the small area where it occurs is not accessible to the public. It is well off the beaten path and difficult to access in the first place. It is legally Endangered, under both the federal Species At Risk Act (SARA) and corresponding provincial Endangered Species Act (ESA). Due to the highly protective intent and language of those pieces of legislation, great efforts are being made by Ontario Parks staff to ensure that no harm will come to this important element of Rondeau's, and Ontario's, flora.

So even if you never get a chance to see this wonderful little plant in real life, hopefully you can enjoy knowing a little more about it via this post, and know that it is still present at Ontario's second oldest and most species rich provincial parks.

Rich forest habitat near the Triphora population