Strange Habits
It is a universally accepted fact that ‘Plants Grow in the Ground’. However, when it comes to our orchids, this statement is not always correct, even though orchids are plants.
Most of us are aware that a large number of orchids grow as epiphytes, they spend their lives , in nature, hanging from or clinging to the branches of trees and shrubs.
Other orchids are lithophytes; they grow on rocks.
Many orchids do grow in the ground as terrestrials, especially those that live in harsh climates that enforce a severe dormant period on these plants.
The term ruderal describes the growing habit of plants that grow on top of the ground, their roots burrowing among mosses and lichens on the surface of the earth (Withner 1994).
 Cephalanthera austiniae |
Then there are plants, including orchids, that grow sub-terrestrially, that is underneath the ground. Their roots and stems stay hidden below and only their flowering parts climb out of their dark bed. Some stay there all their lives, for instance the Australian Rhizantella gardneri, where only the top of the flowers is barely visible from above the soil, making it accessible to fertilizing beetles. It is another way of a plant coping with a harsh environment. These plants are called saprophytes. They live in symbiosis with particular fungi that provide the food for them. Thus saprophytes have no need for chlorophyll; they do not photosynthesize. They are mostly lacking colour, although at times they can be pale pink, lavender or soft brown. They have no leaves, only vestigial scales along their glassy stems. Surprise here: only as recent as 1998, an English researcher J.R. Leakey has decided that the word “saprophyte” is outdated;” there are no ‘saprophytic’ plants” he says. All those that were classified under that name are actually parasites that feed off fungi to be able to live. Their proper scientific name is “Myco-heterotroph”. Is this theory accepted everywhere? One of these saprophytic orchids is the rarely seen Phantom Orchid (Cephalanthera austiniae); others are the Coral Root Orchids (Corallorhiza ssp.) whose roots really do look like white coral, forever underground. Another genus of saprophytic orchids is the tropical Galeolas.
I have read (Richter, 1970) that in Java and neighbouring islands there is one species called Galeola altissima. It has been said that this orchid has the longest stem of all orchids, growing to a length of 150 feet (50 m). That seems quite an accomplishment for a plant without leaves and chlorophyll. How can it happen? It seems that through the help of its micorrhizae this orchid can actually devour large trees (H. Burgeff), so the food source is assured in a tropical forest. When this plant gets ready to flower, it sends long, pale purple stems above the ground, looking for tall support. The natives dislike these trailing vines and cut them down because one becomes very nauseous from eating them. Eventually, there will be flowers on the spooky stems. They appear almost over night, opening all at once into large clusters of hundreds of honey-yellow blossoms, similar to Dendrobium fimbriatum. They have no scent but attract pollinating flies. After about a month, the flowers fade and black capsules appear containing seed that is the largest of all orchid seeds (Beer 1963). The plant apparently dies after flowering.
Many orchids, including saprophytic ones, may not bloom every year. Then it seems that the little Phantom Orchids and the Coral Root Orchids have died – they are not there! One cannot hope to ever transplant these strange creations. If you try, you kill the plant and its fungi. Anyway – I would not really want to put something in the garden or the greenhouse that eats all the wood it can find – would you?
Ingrid Schmidt-Ostrander - Canadian Orchid Congress