This sad looking plant is in desperate need of some attention. It is obviously suffering from the invasive presence of the liverwort. These strange plants are non-vascular Bryophytes and have a growth form, seen here, which is the gametophyte. By that I mean that it only has one set of chromosomes (n) rather than you or me which have 2 (2n). Put another way, they are haploid and we are diploid. They do have a diploid phase but it is transitory and judging by the way they can spread in the nursery, I suspect not so common as their asexual reproduction. This is simply by them producing gemmae in those upturned cups you see in the photograph which are splashed around by rain and my watering can. Each one starting off a new plant. The one which we seem to have this year is probably a species of Pellia, and most likely Pellia epiphylla. Even though it takes time to repot the plants that need it the liverworts are quite fascinating in their own right, even down to having rhizoids, not roots, which are single cells. These can form quite a dense mat just below the soil surface which is why there is little point in trying to weed them out, better to repot before the liverwort grows over the top of the orchid seedling, which may be small but has taken two years to grow that big and still needs help in surviving.
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![]() At this time of year we are collecting and labelling our orchid seeds for cultivation in our laboratory. One of the most important aspects of this is that the seeds are correctly labelled. This often means nearly as much time is spent noting details down as is spent in collecting. One of the reasons for this is that when looked at in bulk all orchid seed, tropical, temperate, epiphyte or terrestrial, they all look the same. Even when looked at in close-up it is apparent the while it may be possible to hazard a guess as to the general type, it is not possible to say with certainty what species it comes from. ![]() These two photographs of orchid seed are a good demonstration. Two quite different species where the seed is structurally almost identical. These are very distinct species and the seed species could be identified from a DNA profile, but visually they are nearly the same. When it comes to closely related species the similarities make it impossible to separate the species, or identify which species they are. In the case of inter-specific hybrids this becomes even more tricky and DNA will not help except where very sophisticated techniques are going to be used. So we spend lots of time making sure seed from known species gets the right label and no mixing takes place so that there is no risk of the wrong plants being sent out to customers. In the case of Twayblade seed it is rather unusual because it is a golden colour, rather than the ginger or brown of most of our orchid species. ![]() This Common Spotted orchid, Dactylorhiza fuchsii, has started seeding quite early this year. It was also one of our earliest plants to flower, in fact it was as early as the Green Winged orchids this year. It has not only set a tremendous amount of seed but it has also started shedding it as well. One of the reasons for pointing this out is a simple excuse to show a photograph of a plant which is part of a project to more clearly define the longevity of individual plants. In this case it was seed three years ago. It is unlikely that it would have achieved this scale of plant growth if it had started as a seed in the meadow, but we grew the seed in culture ourselves, thereby giving it a head start. Another interesting feature of this orchid is that, like all Common Spots, at this time of the year the leaves lose their purple patterns. ![]() This particular plant as you can see has no obvious colour left, but this second picture on the left, shows exactly the same plant, in April this year, and the same leaves that can be seen surrounding the flower spike. As you can see, even though the plant started with a spectacular leaf pattern it has now disappeared. The patterned leaf in this picture is the same leaf that appears on the left of the flower spike in the top picture. I think we shall investigate these things further. |
AuthorDr Wilson Wall, grower of orchids. A scientist by inclination and training. Categories |
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