Tuesday, April 19, 2011

EPOS Meeting, April 2011. Eastern Cape Orchids... And the winner is...

This month's EPOS meeting on Thursday last week was on Eastern Cape Orchids. The speaker, Cameron McMaster, was initially somewhat worried that given the fairly impressive size of most of the blooms on the plant table, the society's members might find the orchid treasures of the Eastern Cape a little pedestrian, if not boring. Of course, that was far from the case...

Mr McMaster is mainly an enthusiast of South Africa's extensive bulbous plant flora (and he runs an African Bulb Nursery) and offers wildflower tours. He clearly spends a lot of time rambling around the countryside, camera in hand taking pictures of South Africa's rich and diverse botanical heritage in some spectacular scenery. Whilst not quite as impressive as the orchid flora of some more tropical places, the Eastern Cape (and South Africa in general) has an impressively rich (if often quite modestly sized) orchid flora, most of which are terrestrial. He several nice picture galleries on his site, including a South African orchid one. I'd include some pictures here, but he prefers not to have his images borrowed - so head on over to his site if you'd like to see them. The talk we saw had even more pictures of even more species! After seeing and hearing about orchids from the length and breadth of the Eastern Cape's summer rainfall dominated orchid flora, he paused (after a surprisingly speedy hour or so!) and asked if we might like to see some winter rainfall (Western Cape) orchid species... Well, that's like offering children sweets - no one is going to turn that down, so we then had a further trip through some of the Western Cape's orchid flora!
Bartholina burmannianaA Western Cape species.
Kirstenbosch Botanical Gardens, 2001

During the talk, many of the members noted that they had seen this or that species here or there - usually with a tragic tale that the population had been fairly recently extirpated either by road construction or other construction work. It seems somewhat strange that it's illegal to dig up a wild plant threatened with destruction and move it somewhere else (in the wild, let alone in your garden), but not illegal to bulldoze it into the ground and cover it in concrete. Mr McMaster noted that in Australia, rare plants are actually marked out so they can be avoided by road crews. I also read the final chapter in Eric Hansen's Orchid Fever about some people in the USA that move endangered slipper orchids (legally). These approaches don't yet seem to have reached the consciousness of local bodies responsible for conservation - indeed, Mr McMaster noted the tragically accelerating loss of South Africa's globally significant plant biodiversity (primarily through changing land use practices and spreading urbanisation) - not much seems to be happening and pleas to such bodies fall on deaf ears.

I can only imagine that in a short while, the only rich habitats will be in scattered wilderness reserves and on the few patches of private land where farmers manage their land in ways that don't damage the flora. I understand the difficulties in policing something like wildflower relocations (and making sure that allowing that doesn't lead to a corresponding increase in poaching), but there must be a way of conducting such "rescue operations" in a sensible and effective manner, perhaps though nature conservation bodies (provincial or national) overseeing volunteer bodies such as botanical societies relocating rare or otherwise endangered plants from place to place.

Senior Management wondered why we couldn't just grow up lots and lots of plants in captivity and "release" them into the wild; my immediate concern was "flooding" wild populations with a huge influx of relatively limited genetic diversity "captive bred" plants. The same thing is problematic in wild animals too - for example, escaping farmed salmon have become so common that they have started to overshadow wild populations along the western seaboard of the USA, particularly in Canada and in Europe. This is not insignificant; around two million salmon escape annually in Europe, against a wild population of around 4 million! Things could go quite poorly for the wild salmon... One of the things you learn about when you take an interest in evolutionary biology is just how much of a role "chance" plays in what genes end up "on top" in the gene pool - and so taking just a few parent plants, tenderly caring for their progeny and then "flooding" wild populations could really mess things up. Remember that many orchid species produce millions of minute seeds, of which one or two might naturally make it to adulthood; rearing them in flasks massively increases the numbers that make it through to adulthood. How well will those plants, which have had a cosseted youth, sheltered from extremes of climate, pests and diseases do in the long term? And their offspring? Of course, there may be times when that is the only option left (when there are no wild plants, or they become incredibly rare) - but whilst there is a reasonable profusion of them left, I think it would be better to "save the species" by moving it, rather than farming it (or waiting until we have to keep the last few grimly hanging on "life support" in a greenhouse). Genetic diversity is the equivalent of a well-shuffled deck of cards - you have more of a chance of countering new (and existing) challenges head-on (and winning) than you would if everyone had the same cards every time, or only a few cards that made pretty poor hands!

Anyway, enough of a rant about the state of the world today, and just how much of a tight-rope we must walk with conservation and development!

The other news of the evening was that our Rhynchostylis coelestis won "Best Species" on the plant table against what I thought was some pretty stiff competition, including an absolutely enormous specimen Dendrochilum, owned by Stan Wedge. We took home a wine glass engraved with EPOS' emblem as our prize. YAY! Of course, this isn't an officially SAOC judged event, so it doesn't get any actual Award, but we were very proud "plant parents" that evening! Some people on Orchid Board asked how I got such great flower spikes on it - I'd have to claim sheer luck to be honest. People seemed genuinely intrigued by the plant; it doesn't seem that obscure a species, but clearly, Senior Management's eye can detect superior plant matter from across a crowded greenhouse - even when it is not in flower! One of the experienced members commented that I should give him a piece of the plant, should I ever divide it - clearly, it's Good Stuff(tm). I also enquired whether it might need to be moved into a larger basket (the one it's in is pretty crowded) but apparently, it's better left where it is for several more years. My reading indicates these plants really hate being re-potted, so that seems like sage wisdom!

As this post has been a bit Spartan with pictures, I'll leave you with some shots I took of the Rhynchostylis the morning after the meeting:
Rhynchostylis coelestis

As usual, you can click on the images if you'd like a closer view.

And of course the guest speaker found out that no matter how fanatical EPOS's members might be about their more exotic blooms, most of us still appreciate the extensive bounty that naturally exists right on our doorstep!

p.s. another really great resource for South African Orchids is on PlantZAfrica.

Tuesday, April 12, 2011

New Plant: Den. Mini (white with red lip)

Bit of a "NOID", a Dendrobium Mini (white with red lip):

Dendrobium NOID Mini (white with red lip)

Sadly, essentially being a NOID, I have little idea what this plant is in terms of it's hybrid ancestry. It's a nice, compact plant, which is a bonus at OOAB, where space is most certainly a limiting factor. I managed to find an extremely similar looking plant through Google, but again, it has cryptic naming which doesn't really elucidate much!

I quite like the way it superficially resembles a Phalaenopsis, but with pointed ends to the sepals (the top and lower left and right "petals"). There is a group of Dendrobium and hybrids called "phalaenopsis", and I guess this would probably fall in there somewhere.Continuing my investigations through Google suggests that most of these "phalaenopsis"-type Dedrobium have Dendrobium bigibbum in their ancestry. This orchid (or rather part of what taxonomists have decided is a cryptic species complex), commonly known as the Cooktown Orchid, is the emblem of the state of Queensland in Australia. The botanists have decided to split it off from the rest of the mega-genus, and it is currently known as Vappodes phalaenopsis. (A rather ugly genus name on my tongue, but YMMV!)

It looks like the buds open quite slowly, so with a profusion of them and with cold, metabolism-slowing winter weather on the way, I imagine it will be in bloom for a long while yet.

As with most Dendrobium, it likes bright light (a bright windowsill should keep it happy, and in warm areas, it would probably be quite happy outside under a tree during the summer, or possibly year round). This particular Dendrobium may not need a "rest" where water is mostly withheld during the winter, but we'll see with time! 

We spotted this plant at the local florist (Casablanca) just over a week ago and had to have it (we've been a bit busy of late with Senior Management's graduation and family being in town to blog much). There were several other tempting orchids there on the day (including a similar purple-ish Dendrobium "mini"), but we managed to restrain ourselves from taking more than one. The label in the pot is from Caro-Lin Orchids, based in P.E.

This orchid is now the 65th member of the OOAB "menagerie"...! 

Tuesday, April 5, 2011

Sundews from Seed - Drosera capensis; some Carnivorous Plant notes.

Quite some time ago I planted some sundew seeds I acquired from a Bid or Buy (South Africa's answer to Ebay) seller, Seeds and All and planted them up in a mixture of moss, peat and perlite and sealed them in ziplock bags to do their thing. This seller has a habit of throwing tons of extra seeds (of plants you didn't order) in as "freebies"; if you look at my Stash over at Folia, all those seeds except the Welwitschia are "freebies" from this source.  I still have to get around to planting the Welwitschia!

Just the other day, I noticed that the Drosera capensis seeds have germinated and put out minute rosettes of sundew leaves! I'm still waiting for three other sundew species (natalensis, madagascariensis and trinervia) and some venus flytrap seeds to germinate, but I'm starting to suspect they're not going to.:(

Anyway, here's a 1:1 macro picture of a few of the little plantlets in all their minute glory!

Drosera capensis - cape sundew seedlings. 1:1 macro.
OOAB's Senior Management thinks that this should be the new OOAB background image...

Apparently, D. capensis is by far the easiest sundew to grow, to the point that it magically self-seeds itself around your collection and is apparently capable of germinating feats that might suggest spontaneous generation! My sincere hope is they go on to be insect eatin' machines of Doom, laying death and destruction upon those small creeping and flying creatures that might wish to snack upon my treasured green things! I'd like some butterworts for the same thing, but I have yet to find any for sale in .za. I also have two Nepenthes pitcher plants (a veitchii 'pink' and an x hookeriana), which have been dubbed "the pod plants" by OOAB's Senior Management. I'm clearly still working out how to grow them as they don't look like the happiest campers. Stay out, bugs, lest you be snacked upon! I'm not sure what looks I'd get if I happened to obtain some Nepethes rajah, which are infamous for (rarely) dining upon rodents, particularly given Senior Management's dearest beloved creatures.

p.s. Yes, I know they're not orchids ;)

Restrepia trichoglossa in bloom

Recently, I've been a bit worried about one of my early birthday presents, a Restrepia trichoglossa. The plant has been looking a bit under the weather (see this thread on Orchid Board). However, I think I have "New Parent Syndrome" and might be unduly worried at every sign of slight upset-ness my precious plants display! In fact, the plant seems happy enough to be throwing out both keikis and now flowers (although these might just be an ailing plant's last, best hope for life after death...!).

I really like these little plants and could definitely see myself owning more... They don't take up much room and have very nifty flowers. This one has a pimpin' pinstripe suit (in funky disco colours), and I bet those "antennae" could get great reception!

Enough words for now - here are some pictures! :)

Restrepia trichoglossa
Bloom on 04 April 2011
Restrepia trichoglossa
Keiki with developing flower
Restrepia trichoglossa
Another keiki.
If my scientific Latin/latinised Greek doesn't fail me, trichoglossa means "hairy tongue"! If you click on the first picture and look at the macro full screen, you'll see that there is indeed a "hairy tongue" on this flower. I might get around to a 2:1 macro of it at some stage See below! I'm not quite sure why the keiki roots seem to be growing upwards - this seems rather odd to me! Once they get a bit longer, I might consider taking them off the mother plant and giving them each their own pot (or perhaps trying one out on some EcoWeb); for now, they get a daily mist to hopefully keep them happy and moist.
Restrepia trichoglossa
2:1 macro of the "hairy tongue"

Given my current concerns over the health of this plant, I'm probably not best placed to give cultural advice, but here are some generalised "tips" for growing Restrepia, culled from my reading here and there.

Restrepia, like most (all?) "pleurothallid alliance" plants, like to be kept fairly damp ("not wet!") and cool - but without suffocating the roots with too much water. Fairly high humidity is usually good for them too, particularly coupled with some airflow from a fan. They will tolerate fairly low light levels; their "ideal" light (the high end) will make the leaves turn slightly reddish (plant sunscreen!). Andy's Orchids recommends 500-1500 foot candles for this species, with Restrepia in general ranging from 500-3000 foot candles. Restrepia can either be grown in pots or mounted; I suspect mounting will only be successful if you're very vigilant with your watering regime and have fairly high (>70% RH) humidity in your growing area. Air movement is apparently important, although not quite as widely mentioned as in Masdevallia culture. I water mine daily with RO water; it's potted in sphagnum moss. Like most pleurothallids, it probably does best with very weak but regular fertiliser doses. I imagine these do very well in humid, cool orchidaria (something I'm contemplating building, but don't know where it would fit!).

An interesting thing about Restrepia is that they'll happily root from leaf cuttings, much like an African Violet - usually in the node where you can see keikis developing in the photos above. With the notable exception of the fairly rare and challenging R. chacoensis, apparently. If you'd like to see how a fellow blotanical blogger M3ma1d does this with African Violets, have a look at the Fuzzy Foliage post on Starting African Violets from Leaves with its embedded step-by-step video. Obviously, Restrepia aren't African Violets, so you might want to choose a slightly different potting medium (Sphagnum moss is probably good)!

I'll leave you with this backlit picture of the flower; when I had it in a beam of sunlight whilst taking the 2:1 macros quickly this morning, there was an amazing crystalline look to the flowers as the light shone through it; hopefully this picture captures some of that!

Backlit Restrepia trichoglossa
Make sure you look at the larger version
(click on it)

Monday, April 4, 2011

An Unexpected Treat (and a little science) - Dendrobium tannii

Back in February, I received a Dendrobium tannii from Plantae as a stand-in for another plant which was not available at the time. It's taken until just the other day to notice that what I thought were oddly spaced leaves were in fact... flowers. The flowers start out green and looking rather "leafy" to my somewhat inexperienced eye. I think the real give-away was when they magically started turning pink...! Closer inspection revealed clearly orchid-esque flower morphology.

Dendrobium tannii in February,
just after being unpacked.
Notice the short canes in the front...
So how does it look now that the flowers are out? Well, those short canes at the front have certainly changed!
Dendrobium tannii flowers
As you can see, they're really packed in there.
No wonder I thought they were leaves when they were still green!
Dendrobium tannii flowers - closeup
D. tannii
Dendrobium tannii inflorescence

Warning for the faint-of-heart - Taxomony Alert!
Dendrobium tannii may not be the correct name for this plant; some people consider this to be a "compact" form of Dendrobium bracteosum, and some refer to it as Dendrobium bracteosum var. tannii. Botanists are constantly revising their opinions of what represents a species within the Orchidaceae and how orchids should best be classified. We can expect a lot of upheavals in "conventional" or "established" nomenclature in the future, particularly as more and more studies using molecular (DNA) information better illustrate the inter-relationships between species, particularly at the generic (genus) level. Of course, this is annoying to hobbyists, but such is life! Many people expect that some of the "mega-groups" (dumping grounds?) like Dendrobium and Bulbophyllum that contain hundreds or even thousands of species will ultimately get broken down into many much smaller genera, with just a few species ultimately "belonging" to that particular genus. Cue wailing and gnashing of teeth amongst growers (and much re-labelling!). I suspect some people will stick to the "tried and true" names for a while, as there can be a lot of flip-flopping when taxonomists haven't quite made up their minds in the face of new ideas and new information. And of course, sometimes you're attached to the old name! (I spent quite a few years as a [fish] taxonomist-in-training, so I appreciate both sides of the argument!). Ultimately, I think it will be good to have an accurate phylogenetic naming/classification scheme within the orchids; I imagine there are quite a lot of polyphyletic and some paraphyletic groups which need to be sorted out. It's going to take some time to get there though, with ~20-30,000 species!

People have managed to cope with the loss of favourite names in science before. The poster child for the rules of taxonomy, at least in Zoology, must surely be Hyracotherium, which could be rather more beautifully referred to as Eohippus, but unfortunately, (if I recall correctly) Owen named its fossilised teeth(!) Hyracotherium long before (well, 35 years before) anyone realised they belonged to a possible ancestor of modern horses, and the rules say the oldest validly published name wins. Eohippus means "dawn horse", whilst the significantly less mellifluous Hyracotherium means "Hyrax-like beast". Amusingly enough, as enamel is so resistant to decay and therefore fossilises relatively easily, palaeontologists (perhaps I read it in one of Stephen Jay Gould's books/essays?) have made remarks about the fossil record of mammals mainly being along the lines of "teeth slowly evolving into different teeth"...

Of course, give it enough time, and the classification will be wrong again - orchids are still busy evolving away (as is everything else!). I have often idly speculated on what will happen to taxonomy and systematics once the living populations have diverged enough from the holotypes, and quite how we're going to reconcile the increasing importance of genetic techniques where holotypes are not amenable to such study... Fortunately, the first half of this paragraph is not something we'll have to worry about in our lifetime, but the second half (matching genes up with holotypes that have irreparably damaged DNA) is going to be tricky. I suspect eventually groups like the ICZN and ICBN will have to establish rules, perhaps some sort of "geno-neotype" ranking - and ultimately, what they're going to do about chronospecies which have arisen within what will then be recorded history!

And now, back to the plants...

Growing-wise, I believe this plant likes things to be a little on the "warm" side and bright light ("Cattleya light" - 2,000-4,000 foot candles); here's what IOSPE has to say about bracteosum:
A small to medium sized, hot growing epiphyte with tufted, erect or pendulous, terete, slender at the base, fleshy and thicker above, to 9 noded, yellowish stems covered in papery sheaths and carrying up to 6 ligulate to oblong, tapering at both ends, coriaceous, rich green leaves that blooms in the spring through fall on 1 1/2" [4 cm] long, pendulous, dense racemes that have fasciculate, ball-like clusters, arising from the nodes near the apex of older pseudobulbs, with 3 to 8, scented, waxy flowers and are found in Papua and New Guinea at elevations of 0 to 700 meters, and is an epiphyte of forest trees and mangroves in rainforests often along rivers and coastlines.
Given the way this plant is growing, I suspect it blooms on "old" canes. IOSPE suggests that bracteosum is fragrant, but I can't smell anything yet; maybe the flowers are still maturing - or perhaps tannii is a valid species, which is unscented (but then again, even within well established species, there are differing degrees of scent...). Culture notes I've read around the place seem to suggest this plant should dry out a little (but not bone dry!) between waterings to prevent root rot.

It's rather fun when your plant's "leaves" turn out to be exuberant pom-poms of flowers! I wonder what other surprises lie in store in my plant menagerie?