Sunday, July 4, 2010

Cymbidium tracyanum

Cymbidium tracyanum 'Atlantis'

I just love Autumn in my shadehouse. The cool dewy mornings. Fogs in the valley. Still air filled with the smell of decomposing vegetation. The smell of Cymbidium tracyanum wafting through the shadehouse, along the verandah and past the back door. The sweetly spicy smell of the Cymbidium contrasts with and compliments the other smells of autumn in the Australian forest. This smell signals to me the start of the main early Cymbidium flowering season. I know in a few weeks the frail looking but incredibly long-lasting C. erythrostylum will be blooming. It is also a reminder that it is time to plan my birthday dinner!

Cymbidium tracyanum is one of those species that can not fail to impress. It is a large and imposing plant. A well grown plant will bring ooh's and aah's from the uninitiated and the most hardened orchid buff. It's exotic looking flowers and fragrance are sufficiently intoxicating for everyone to be taken totally into it's spell even if only for a few minutes. Reality strikes when the size of the plant is contrasted with the growing space of the collector. Hmm, lets see, one specimen plant of C. tracyanum or ten 8 inch pots of other more restrained species or hybrids?

Of the larger-flowered Cymbidium species, Cymbidium tracyanum is one of the largest plants with the largest flowers. Plants are commonly about a metre tall with large pseudobulbs (up to 15cm tall) and long arching leaves (up to 1m long and 4cm wide). Flower spikes are usually up to a meter or so long and produced at an angle. In my plants, spikes are commonly disposed at a forty-five degree angle and gently arch from about midway. Other forms have flower spikes that are nearly horizontal or point up at a 60-70 degree angle and these spikes may or may not arch. Each spikes produces up to about 20 flowers and the flowers are commonly 10 - 15 cm wide and a little less high.

Cymbidium tracyanum was one of the early imports to the gardens of the west. It first came to the attention of the gardeners of a Mr. Tracy from Twickenham in England. I say 'first came to the attention of' because it was not an expected part of a shipment of what was meant to be C. lowianum. When it flowered, there was obviously a fair degree of excitement. It was immediately taken to the Royal Horticultural Society Orchid Committee and judged as being worthy of a First Class Certificate. It was named shortly thereafter in the Journal of Horticulture, and surprisingly, named and described a few days later in a competing journal The Gardeners' Chronicle. It was formally illustrated the following year in The Gardeners Chronicle. I can not image what it would have been like for the gardeners at Mr. Tracy's greenhouses when this plant flowered. Below is a picture of the plant that they first 'discovered' and that was awarded on the 9th of December 1890. This plant has been passed down through the generations and is still grown by many people around the globe.

Cymbidium tracyanum FCC/RHS

It is interesting to note, that at first, it was not clear where plants of C. tracyanum were coming from. Several plants showed up in shipments of C. lowianum and it was one of these shipments, from a known area, that alerted the collectors where to look. The third importation, with the known locality, did not flower until 1896. Upper Burma (now Myanmar) was the place to look. Thankfully, by 1900 plants flowered that were collected by a man named A. F. G. Kerr. He found these plants near Chieng Mai in Northern Thailand. It wasn't until 1940 that the actual habitat of C. tracyanum in the wild (Burma) was described by Francis Kingdon-Ward. His description of the habitat includes the phrases 'wet evergreen hill forests' and 'Growing in the fork of a tree overhanging a stream in a deep gully'. One can only imagine the sight of a fully mature plant of C. tracyanum growing high in a tree.

It always fascinates me that some people and even some botanists have difficulty identifying this plant. Granted, it is hard to decipher the finer details of a flower from a herbarium sheet. When I read that some botanists could easily confuse C. tracyanum and C. hookerianum from the herbarium sheets my immediate thought was how? Have you ever tried to press a cymbidium flower? They all end up looking about the same. Most pressed orchid flowers are a plain dark brown with all the subtleties of shape and colouration lost. There are however some very simple and clear features that separate C. tracyanum from all the other large-flowered species even when they are squashed and dried.

The first and easiest-to-tell feature of C. tracyanum that jumps out at you, even from a herbarium sheet, are the two callus ridges on the labellum that are densely covered in long transparent hairs. The labellum also has long hairs scattered all over it, particularly along the edges of the sidelobes. In all the pictures presented here you can easily see them. Some people refer to these hairy callus ridges as 'Toothbrushes'. An apt analogy. Cymbidium hookerianum also has hairy callus ridges and hairy sidelobes on the labellum, but the hairs on the callus ridges of C. hookerianum are few and far between. Hardly comparable to a 'toothbrush'. More like the first few hairs on the chin of a teenager!

The petals are a dead give-away. In the terms of the botanist they are 'falcate'. This literally means 'curved like a sickle'. This varies in degree between different forms of the species: some are only lightly curved, more like a scythe, others so tightly curved that they nearly make half circles. The spots and stripes of the flowers, while certainly distinctive, are shared by several other closely related species.

Another feature, not commonly preserved on herbarium sheets, that separates C. tracyanum from all of the other larger, cool-growing Cymbidiums is the upward-pointing roots. These roots are about 3cm long and form along the sections of the main roots closest to the base of the plant. These types of roots occur in several other Cymbidiums but mainly amongst the 'hard-leaved' tropical types. It is commonly thought that this type of root configuration helps the plant to catch falling organic matter or to provide extra air to the roots. Literally the Cymbidium equivalent of pneumatophores in mangroves or 'knees' in Swamp Cypress.

For any grower of C. tracyanum you would have to wonder how such a distinctive plant could be confused with any other Cymbidium. A couple of advantages a grower has is their sense of smell and the ability to see the plant in growth. Being complex animals that can process multiple stimuli at one time, we humans can easily and readily distinguish between various species with just a little practice. The fragrance of C. tracyanum is very distinctive: sharp, strong and spicy. It is a deep fragrance: very rich, complex and cloying. Once you smell it, it will stick in your brain. Of course, all the shape and colour of the flower is readily visible in a growing plant. A feature not apparent on herbarium sheets and not listed very often in the literature, is how the flower spikes are produced. Unlike almost all of the larger flowered cool-growing Cymbidiums, except for C. erythrostylum, C. tracyanum produces it's flower spike on the maturing new growth, before the pseudobulb is fully formed. The spike doesn't actually arise from the very base of the pseudobulb but from amongst the cataphylls (leaf-like bracts) or basal leaves.

You would think that a species such as C. tracyanum would have been used extensively in hybridization. Well in many respects it has been, but not as much as you might think. To date is has been figured as a parent exactly 100 times in first generation hybrids. It is more informative to see how and when it has been used. There was a flurry of breeding soon after its 'discovery' but once Cymbidium insigne came on the scene in 1901, with its tall spikes of white or pink flowers, C. tracyanum lost favour. The hybrids produced with C. tracyanum as a direct parent are generally what are called 'reptilian' in colouration. Lots of browns, yellows and greens with spots and stripes. Present day growers call these colours 'muddy' if they are mixed with white or pink. Oh the fashion of the orchid world, giving way to light colours and tall spikes in preference to interesting colours, fragrance and tons of 'personality'.

An interesting side note is that C. tracyanum has been used only 29 times as a pod parent (mother) but 71 times as a pollen parent (father). Some have suggested that there are clones that are fully or partially sterile as a pod parent. This may or may not be true. From what I can find out this may be gardening lore. Certainly, the disproportionate number of times it has held a pod compared to contributing the pollen, makes one pause and question.

The influence of C. tracyanum did not fully wain. There were second and third generation hybrids that proved to be spectacular. Some of these early hybrids, some now approaching 100 years of age, are still popular. Cymbidium Grand Monarch is probably more popular now than it has ever been. The hybrid C. Lustrous, is being re-introduced in to present day breeding programs. Even lowly old C. Doris, the stalwart of every Cymbidium collection in Melbourne, Australia, has been remade using selected parents. The results are far removed from the original cross and highly desirable in their own right.

Now you would think that many of the more complex hybrids created with C. tracyanum in their background would be spotted. Some are, many are not. The main features of hybrids with a high proportion of C. tracyanum in their ancestry are: early flowering, easy flowering, large flowers and a range of colours except for white. The classic shape of C. tracyanum tends to be dominant in first generation hybrids but is quickly lost in the second and third generation. Many of the early hybrids were in the yellow/green range but there are good examples of pinks and orange as well.

Unfortunately, there is a major fault with the early hybrids and indeed all first and second generation hybrids containing C. tracyanum. Although the flowers are beautiful on the plant, they tend to be a bit shorter-lived than hybrids produced from other species such as C. lowianum. The other fault, from a cut-flower growers point of view, is that the flowers wilt within hours of being cut. For some reason, the stems do not draw water fast enough to keep the flowers turgid. I guess we just have to content ourselves with growing them as potted specimens and enjoying them as is. Let me see, is there a problem with that?

Orchid growers being orchid growers are not content with just one 'normal' form of the species. Well at least this orchid grower isn't. As mentioned earlier C. tracyanum has been collected many times from the wild and from right across the range of the species. Like all wild-collected plants some are more attractive than others. Flowers vary in size and colour intensity. Some are more free-flowering than others, although all the ones I grow are amongst the easiest of Cymbidiums to flower.

Until recently most people selected the darkest forms they could find. Some of the older clones that were paler or had less spotting were thrown out in preference to the next darkest clone to come down the track. Some of these clones, such as 'Dark Boy' and 'Black Knight' and 'Red Knight' are incredibly dark red/brown with very little of the greenish/yellow base colour showing through. At the other end of the spectrum are clones such as 'Tamborine' and 'Randall' that more closely resemble the colours found in the 'average' wild plant. Interestingly, albanistic and albino forms of the species have found their way into cultivation. These forms go under the names of 'Alba' for the true albino and 'Albanistic' for an extremely pale form. In a recent book called The Genus Cymbidium in China, a species called C. gaoligongense was described. It is now widely recognized that this species is actually an an albino form of C. tracyanum. It is a clear yellow with a white labellum and orange-lined sidelobes.

Over the years interest has turned to procuring better and better forms of the species. Hybrids between selected clones have produced a range of colours and in many cases increased the size and number of flowers on the spike. It is really hard to say which of these intraspecific hybrids is the nicest. Each has a quality all their own. Below is a selection of various clones of C. tracyanum. You be the judge.

Cymbidium tracyanum 'Atlantis'

My friend Julian has been growing this plant for many years. It is a very robust grower that commonly produces two spikes from each pseudobulb. Last year his plant had 27 flower spikes on it. The plant was 1.5m across with the flower spikes taking it to well over 2m wide and 1.5 m high He was going to take it to the local show but could not fit it in the van. Mind you, even with help it would have taken 4 men to lift it.

Cymbidium tracyanum 'Jay Pruette'

This clone was a wild collected plant supposedly imported from Thailand. Unlike many of the other clones of C. tracyanum, the background colour of this form is green but fades to yellow just before the flowers die. I particularly like the reddish patch at the base of the petals and sepals. In real life, especially with the oblique autumn sun hitting it, this red patch just lights up.

Cymbidium tracyanum 'Randall'

This is the clone that I have had for about 25 years. It is the most rampant growing form that I have. Unfortunately, the flower spikes are generally produced at the same level or lower than the leaves. It needs a little bit of encouragement to display its flowers well in a pot. I can imagine that this form would be particularly attractive viewed from below when growing in a tree. The green mass of the leaves providing the perfect foil for the multiple spikes of flowers below. Paler flowered than many other clones but also larger flowered than many. This plant was brought back by a friend from a collecting trip to China.

Cymbidium tracyanum 'Royale' 4N

This is not my plant nor my photo! This plant is the result of a crossing carried out by Kevin Hipkin of Royale Orchids. This was a purposely bred intraspecific hybrid of two particularly nice forms of C. tracyanum. The resulting seedling were treated to convert them to tetraploids. One of the unfortunate things that happens with the 4N versions of C. tracyanum is that the typically 'sickle-shaped' petals tend to be a bit less so. On the up side, the intensity of the spotting on the labellum tends to increase.

Cymbidium tracyanum 4N (un-named form raised by Julian Coker)

This plant flowered in a group of seedling of the cross C. tracyanum 'F1' X C. tracyanum 'Albanistic' from Andy Easton of New Horizon Orchids. This cross produced some amazing looking plants but for my tastes they lacked some of the charm of the more wild-looking forms. My tastes are obviously my tastes. This plant has a legion of admirers including it's owner. Big fat stems and big fat flowers with amazing colour but alas, only about 12 flowers on a stem.

Other clones from the above cross turned out to be 2n. These varied in colour intensity and configuration. Many of them were beautiful in their own right but were again a step away from the forms found in the wild. It is interesting to see how these intraspecific hybrids accentuate different features found in the wild species.

Cymbidium tracyanum 'F1' X C. tracyanum 'Albanistic' 'clone 1'

Cymbidium tracyanum 'F1' X C. tracyanum 'Albanistic' 'clone 2'

Cymbidium tracyanum 'F1' X C. tracyanum 'Albanistic' 'clone 3'

Now the story doesn't end here! Although interest in using C. tracyanum as a parent declined markedly after WW1, there has been a recent resurgance in its use as a parent and capturing its qualities in second and third generation crosses. Kevin Hipkins in Australia is one of the leaders in this field although there are many others as well. These 'Children of Tracy' will appear in a future blog. Be prepared for some suitably 'dark' names. Some of the names of these hybrids are truely disturbing. Pywacket, Valley of Death, Death Wish, Road Rage and the soon to be named Ethanasia!!!