Late summer orchids of Rondeau, all are species at risk!

 There are several highlights for botanizing later in the summer. Certainly the main highlight for me is to check on three orchid species that are found at Rondeau, all of which are quite rare in Ontario. One is so rare that its only Canadian location is at Rondeau. Another one is quite restricted, but so very small that the average person would not even see it. The third, and latest flowering one, is rare, but relatively widespread in the park and generally more visible.

 Keen botanists will likely already know the three I am talking about. The first, and rarest one, is the Nodding Pogonia (Triphora trianthophoros). 

Its peak time of flowering is typically the third week of August, although on rare occasions I have seen one or more in flower on even the last day of July. This year I went out into one of its best known locations on August 1, just to see what was happening, and was quite surprised to see several in flower. One even had a double flower!

The tricky thing with this orchid is its flowering strategy. All the buds develop to a certain stage, and then remain as is. It takes a fairly significant drop in the overnight temperature to trigger the buds to open on the morning of the second day following this temperature drop. All the buds that are ready will open, but just for a single day, and it may be a week before the next suitable temperature drop triggers the next set of buds to open.

The weather this August was anything but suitable for this flowering strategy. An overnight temperature would seem suitable, but then the next three nights would see the temperature drop even more! I think the plants were a little confused with this abnormal sequence, and as a result, their flowering was difficult to predict. On more than one occasion I went out expecting, or at least hoping, to see some in flower, but in some cases they flowered the day before and were not worth bothering to photograph. And the next set of buds were not well developed at all. This next photo shows what a single plant looks like, from a distance of about 6", with a 100m macro lens! They can be easily missed, even when one knows exactly what to look for, so I seldom go out unless I am quite sure they will be in flower, and if it is the wrong day, I don't spend much time looking so as to not accidentally step on them.

I do know where some are likely to be found, even if not flowering, and by being extra careful, I managed to find some that were tucked beside a fallen log, and almost impossible to see. This next photo is of a pair of even tinier plants with very undeveloped flower buds, and again, photographed with a 100mm macro lens from a close distance. The plants are merely 4-5 cm high. Even at that, I greatly cropped the photo to get this.

Overall it was one of the poorest years I can remember in my 50+ years of monitoring this endangered orchid. Probably the relatively dry weather at a critical time was partly the cause. However I did manage to get a few photos. These next two were taken in the 3rd week of August window. All were almost pure white, and while I always hope for some with a magenta tinge that I find even more attractive, the second photo is the only one that had even a very slight magenta tinge. Ones with a magenta tinge usually occur towards the end of the flowering season. Oh well, maybe next year.

 After blooming, the seed pods develop, as this next photo shows. Upon ripening, the seed pods will become erect, and start to dry, with the sides of the pod starting to split open so that a slight gust of wind will cause the seeds inside to disperse.

The second orchid I referred to, is about the same size as the previous one, and at least once the flowers open up, will remain open for several days. However for the more common variety of this one, Autumn Coralroot (Corallorhiza odontorhiza) which is also rare, the flowers don't open, but are self-pollinated! The rarer variety, known as Pringle's Coralroot and shown here, has flowers that do open. This first photo shows a group of four plants.

A closer look at the arrangement of flowers.

Closer....

And finally, a 'head-on' view of the lip of a single flower, which is probably only about 4 mm wide.

Not exactly a show piece for the horticultural industry, but an interesting orchid nonetheless, and it is native!

The third, and last orchid to be found flowering at Rondeau is the more common of these three. It is known as Great Plain's Ladies' Tresses (Spiranthes magnicamporum).

I found my first one with a few of the lower flowers starting to open up on September 13.

A couple of days later, there were a few more starting to open.

It is rare that all of the flowers are open at the same time, but sometimes most are. There are other species in the Spiranthes genus that look similar. A couple of the key characteristics of this one is that when in flower, it has a 'fragrance' that I think is similar to hot plastic. But without getting close enough to smell it, a close look shows a slightly yellow/tan colour well inside an open flower. None of the other Spiranthes have this coloration.

There is some slight hairiness to the outer white parts of the flower, and the sepals flare slightly back if viewed from the side.

 That's about it for Rondeau's orchids for this year. But by next May, another one of the 19 species of orchids will appear. Can't wait!

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Orchid hunting

As much as I like birds, I get side-tracked from time to time, and there are so many things to get side-tracked with!

Last weekend I was on the prowl for an orchid species I hadn't seen in probably 35 years: Ram's Head Lady's-slipper (Cypripedium arietinum). It is fairly widespread in Ontario and elsewhere, but never common, and certainly not here in southwestern Ontario. I knew this species was likely still around in the greater Ipperwash area, as it used to occur (and maybe still does) in Pinery. However I recall hearing years ago that the Pinery population had declined significantly.

A friend gave me some directions to where I was likely to find it. With directions in hand, and a fairly good idea of the crown land layout that it was on, I headed out. As it turned out, it was closer to the beginning of the unofficial trail than I was expecting, so actually went at least a couple of hundred metres past it. It is a tiny orchid, barely 12-15 cm in total height. The sun was bright, and so the contrast and shadows did not make it easy to see. But by going well beyond it in my search, I came across several other orchid species.

This is Pink Lady's-slipper, a.k.a. Moccasin Flower (Cypripedium acaule) and is huge by comparison. There were at least a couple of dozen of these in flower, as well as numerous sets of leaves which will not produce flowering stems this season.

Another orchid I came across was Hooker's Orchid (Platanthera hookeri). I only saw basal leaves, no flowering stems, although it is more plentiful at another part of this site, and could be in flower now. It isn't nearly as colourful as the previous orchid, obviously, and one can easily walk past without noticing it.

Flower of Hooker's Orchid

I saw leaves of the Large Yellow Lady's-slipper, but none in flower. Again, it is more common elsewhere, not far from the Hooker's Orchid, and could be in flower very soon.

These next two photos show the target species. As mentioned, it is quite small, and easily overlooked. The macro lens used almost to its fullest was necessary to get these shots. I noted only two flowering stems and another 5 non-flowering plants. It is considered very rare in southwestern Ontario, and perhaps the only remaining population in Lambton County. It is likely the southernmost population in Canada.

Of course on the sandy pine forests of the Ipperwash area, there are other interesting, non-orchid species. Since I don't see them in Chatham-Kent, I took advantage of a healthy population of several species here just waiting to be photographed. This first species is Fringed Polygala (Polygala paucifolia), sometimes known as Gaywings. It really is a pleasing sight on the shaded forest floor.

A less colourful but still interesting plant is Starflower (Trientalis borealis).

In a nearby location, the Karner Blue Sanctuary owned by Lambton Wildlife, is a good population of Wild Lupine (Lupinus perennis). Wild Lupine is critical for the survival of the Extirpated Karner Blue Butterfly, which used to occur at this site. It formerly occurred in the St. Williams Forestry Station in Norfolk County near Long Point, as well as Pinery Provincial Park. Some of the reasons for this dainty butterfly's extirpation are controversial, but it is largely due to some ill-advised management of the habitat. And that could be the topic for a completely separate blog post.

Some late season orchids of southern Ontario

The subject of orchids is of interest to a great many people. The average person would not be aware of the fact that there are approximately 60 species of orchids growing wild in Ontario, and 18 of them are found at Rondeau Provincial Park. There are actually 19 species that have been recorded for Rondeau, although one, the Helleborine (Epipactis helleborine) is not native.

I wrote about early season orchids quite some time ago, and you can find that post here. This post will carry on with the orchid theme, but focus on species one might find in the later part of the season.

One of the orchids currently in flower at Rondeau is Small Green Wood Orchid (Platanthera clavellata).

 These photos were actually taken a couple of years ago. In checking some of the plants yesterday, I only noted a couple of individual flowers actually open, but in the next few days they should all open up. As one can see from the photos, this orchid isn't spectacularly coloured, and can easily be missed unless an observer knows what to look for. Case in point: they are growing on this rotting log in the slough, which is covered with lots of other vegetation!

The sloughs are, comparatively speaking, full of water this year, making access to such fallen rotting logs difficult. On occasion, one can find them growing in the mucky soil at the edge of the slough.

An orchid that may still be in flower, but does not occur at Rondeau is White Fringed-Orchid (Platanthera blephariglottis). It has been recorded in wet prairie north of here, as well as in fens and bogs. I photographed this orchid in a beautiful bog in Huron County a few years ago.

Somewhat similar in structure but very different in appearance to White Fringed-Orchid is this next one, the Yellow Fringed-Orchid, although it is more orange than yellow.

Sadly this one is likely extirpated (gone) from Ontario. If it were still present, it would likely be in flower in late July to early August. There were historical records from savanna habitat in the Leamington area prior to 1901. And no, I am not old enough to have seen this there, nor did I discover a time machine.....I visited a very nice prairie/savanna area in the greater Toledo, OH area with two other orchid hunter/photographer types in the late 1980s where some of these fabulous plants still occur. The photos here are scanned from my slides taken during that memorable foray.

An attempt was made to grow some plants from seed in the mid-1990s and plant the young plants in promising habitat in the Ojibway Prairie area, where other historical records indicated they once occurred. Follow-up searches to date have not indicated that the plantings were successful, but it takes a few years for plants to mature and flower and it has been ten years or more since anyone last investigated.

One of the rarest orchids in Canada is one that will be flowering as soon as early August: Nodding Pogonia (Triphora trianthophora). It does occur at Rondeau, and is currently the only known location for it in the entire country.

I wrote extensively about this endangered orchid in a previous post, which you can see here.

Towards the middle of August, one of the several species of Ladies'-tresses orchids will appear. A rare one, which does not occur at Rondeau but on rare prairies elsewhere, is the Southern Slender Ladies'-tresses (Spiranthes lacera var gracilis). Note the spiralling arrangement of flowers, each of which as a distinctive green centre.

In very early September, one may be able to find one of the smallest of our native orchids, the Autumn Coralroot (Corallorhiza odontorhiza). It has a flowering and a non-flowering form, yet both appear to produce seed. It is about the size and diameter of a pencil, but with its brownish-purple stem and diminutive or non-existent flowers, is very difficult to find even when you know where it is. This next photo shows it in all of its non-flowering glory, greatly magnified!

Another Spiranthes is the Yellow Ladies'-tresses (Spiranthes ochroleuca). One of the sites in Chatham-Kent seems to have been destroyed, but another small population on private property is still around. I photographed this in September of 2014, although it is a little past its best. It has a creamy yellow centre of its flower.

The largest Spiranthes in our area is Great Plain's Ladies'-tresses (Spiranthes magnicamporum), appearing at Rondeau in good numbers by mid-September and lasting until about the first of October. Its flowers are relatively massive compared to the others in that genus, and it has a distinct scent. Some say it smells a bit like vanilla, but not to me. I think it smells faintly like a soft plastic toy that has been left in the hot sun for too long! Not sure what that says about my olfactory.......

The smallest Spiranthes that grows in Ontario, but has yet to be found at Rondeau, is Oval Ladies'-tresses (Spiranthes ovalis). One can tell from this next photo, where it is on the left and S. magnicamporum is on the right, just how small it is.

It is also the latest flowering orchid we have, often not beginning to flower until about the end of September and continuing well October. I even found one still flowering on November 11 one year. It was first found at Walpole Island in the early 1980s, but seems to have disappeared from there. However it is known from several locations on Pelee Island.

Oval Ladies'-tresses

So there is a bit of information on some of the orchids present in southern Ontario in the latter part of the season!