These colonies of Sphatoglottis plicata and Spa. plicata var. alba were obliterated when the road was repaired from damage

These orchids were growing on a fern prairie next to highest point of highway 10 in Puerto Rico.  Unfortunately, the road on this spot, started cracking and slumping.  A massive rework of the down slope side of the road was done to protect the road from further damage and to repair it.  The whole area was denued and reshaped.  Some day I will return to see if the orchids have returned.  However these particular orchids are abundant in the extreme in certain estreches of this road.  In this places even constant removal of plants by people that stop to uproot them, seems to make no dent in the populations.

Sphatoglottis plicata, a weedy invasive orchid, near Mt. Britton, El Yunque, Puerto Rico

I found this orchid blooming on the roadside near Mt. Britton in el Yunque forest.  Unlike Spathoglottis populations at lower altitudes, plants were widely scattered and seemed confined to disturbed areas.  No white flowered plants were seen.  The plant whose flower I photographed had several developing seed capsules.  I recall finding Eulophia plants in this spot in the early nineties, I have visited the area several times in the last few years and have never found them.  Of all the terrestrial orchids in this part of the forest, Spathoglottis is the most conspicuous due to its brightly colored flowers.  No evidence of damage to the flowers by beetles was seen in the plants near Mt. Britton.

Dendrobium gone wild! Dendrobium crumenatum in San Sebastian Puerto Rico

Dendrobium crumenatum, known as the pigeon orchid, is ubiquitous in orchid collections in the island of Puerto Rico.   I suspect the two main the reasons it is so common in collections are, one, it can grow well under Puerto Rico’s climatic conditions and two, it is generous producing plantlets along its flowering stems.   Also, it can stand utter neglect and can survive a wide range of light exposures from full sunlight to deep shade.

The flowers of Den. crumenatum last only one day, but this is compensated by the fact that the plant blooms every time there is a strong shower that lowers the temperature 10 degrees Fahrenheit.    The flowers are strongly fragrant and a big plant can have dozens of flowers at the same time.    As a result of this orchid capacity to survive, and even thrive, with minimal or no care, many people simply tie a plant to a tree and essentially forget about it.   If the location is favorable Den. crumenatum can grow into a huge plant with many canes.

In 1984, I visited the garden of Dr. Juan A. Rivero, he had many types of orchids, growing both on trees and in pots.  I noted that there was a seedling Den. crumenatum in the trunk of a tree.  Dr. Rivero told me that the plants would set seed and that some plantlets had appeared spontaneously on the trees.  The next time I saw seedlings growing feral was in January 2012.  In January 2012, I visited the city of San Sebastian to participate in the Festival de la Novilla.   This festival is named because a young cow is adorned with ribbons and paraded through the streets of the city.  Needless to say lots of drinking and merrymaking happens, but I digress. As I was walking along a city street I saw a large plant full of blooms inside a fenced garden.    I stopped to take some photos and then I noticed that in one of the trees that lined the street there were seedlings of this Dendrobium.

The seedlings were growing on the trunk, from a little bit below eye level to high in the branches.  It counted a dozen seedlings on the tree.  Some were close to blooming size and others were only a few inches long.  The tree where the seedlings were growing was about twenty feet away from the site of the specimen plant, which I suspect was the parent.

As I explored the area, I noticed there were a number of orchids on the nearby trees, with the exception of the tree with the seedlings, all were in the gardens and clearly put there by humans.   There was a large plant of Dendrobium cucullatum, a clump of Dendrobium Jacqueline type, a strap leaf Vanda and many Arachnis plants, probably from their look Arach. Maggie Oei.  

Given that the seedlings of Den. crumenatum are becoming established with no human help, and that locals clearly love to see orchids on their trees, I would think it will stand little difficulty colonizing the area.   I checked other trees near the one with seedlings but no other had seedlings on them.  Maybe next year, as I go to the Festival de la Novilla, I will go and see how they are doing.

 If you notice any exotic orchid growing in the wild in Puerto Rico, please contact Prof. Ackerman of the University of Puerto Rico in Rio Piedras.  He is studying invasive orchid species and will appreciate the information.   It is important that the information on the location of the plants be as precise as possible.

Spathoglottis plicata, a weedy invasive exotic orchid that can go viral on you.

A mature fully expanded flower

A freshly opened flower still in pristine condition

Notice the many seed pods

A small patch of fern prairie in the Rio Abajo forest showing about a dozen plants on bloom

The purple color form

The damage that the flower beetles inflict on the flowers is clearly evident in this photo

 
The first time I saw this species growing in the Karst region of Puerto Rico it was back on 2005, on the sheer wall of a haystack hill, these hills are called locally “mogotes”. At first I thought they were flowers of the fabled alba form of Bletia patula. But on closer inspection the flowers turned out to belong to a plant of Spathoglottis plicata with white flowers that was part of a small colony growing on a ledge just over a tiny water seep.


I wondered if I could ever find a plant of this species on a more accessible spot so I could photograph the flowers, little I suspected the enormous success this plant would enjoy colonizing the areas around the road. In the next few years I started noticing that the plants were popping up all over the place. By 2010 these plants have become absurdly common on the roadsides of the highway 10 to such an extent that continuous collecting by passerby doesn’t seem to make any noticeable dent in their numbers. I have been to some fern prairies where you can see hundreds of blooming plants and an uncounted number of smaller plants.

On first sight this degree of abundance is a bit shocking given what we know about the difficult odds that orchid seeds face in the wild. But when I examined the plants and their inflorescenses the reason for their abundance became clear. All the plants that had inflorescences were laden with seedpods and it seemed as if almost every single flower was either pollinated or had set seed by self-pollination. As a result of the heavy seed production the population on this fern prairie is broadcasting onto the environment a staggering, mind- numbing quantity of number of seeds. The consecuence of the massive number of seeds that the plants produce is that even if only one seed in a million survives to grow into adulthood to reproduce the population will thrive and grow.

One peculiarity I have observed in Rio Abajo is that the white flowered plants are taller and an order of magnitude more common than the purple colored ones. When I have seen them in the same areas, the white plants dominate the sunny centers of the prairie and the purples ones grow in more shaded spots and the areas where the prairie borders on the forest. Native orchids can be found growing in the same areas as the Spathoglottis but in comparatively tiny numbers. The purple and white forms seem not to cross as I have never seen any intergrades even when the plant are growing cheek to jowl.

In the Rio Abajo Forest Spathoglottis distribution seems related to human activity and the disturbance of the soil. I have not found plants of this species in pristine areas inside the forest, away from the roads. However I am still finding plants here and there in spots along the road that enters into the heart of the forest so it is probable that in the near future this species will be able to colonize new areas deep in the forest.

Generally I am against the collecting wild growing plants, unless for scientific or to rescue them from destruction, because this depletes the populations of our native orchids but in this case this is a moot point. This plant is not native and since it is a wildly successful invasive weed it is not likely to be affected in its abundance or capacity to spread by being collected by humans. But there is a different, unexpected reason not to invite this species into your orchid collection. The reason is related to this plant impressive ability to produce seeds.  You should also be aware that collecting plants in state forests is prohibited by law, even if they are obnoxious weeds.

The reason not to bring this plant into your orchid collection is that the seeds of this plant are much more likely to germinate and grow than any other orchid I know. Whether they are more viable than the norm or less fastidious in the choice of their fungal partner or simply because so many of them are produced but the consequences are the name no matter the cause. As a result of the amazing capacity of the seeds of this Spathoglottis you will start finding seedlings in the pots of other orchids, under the benches and on the flower beds in the garden. I am sure most people will be delighted to see a seedling orchid appear in their collection. But this delight disappears quickly when one discovers that seedling Spathoglotis are growing at rocket speed on the pots of that rare, finicky orchid that only grows, and slowly at that, if watered at dawn with water derived from dew drops gathered by hand after midnight from rose petals and that will die if subjected to the slightest disturbance of its roots.

I have had trouble finding flowers of this species in good condition in the wild. Almost every inflorescence hosts one or more flower beetles that damage and disfigure the flowers. The beetle populations seem to wax and wane so at times it is possible to find a few flowers in pristine condition, but most of the times I have visited the areas where this orchid grows virtually all the flowers were damaged to some extent. Isolated plants seem to fare much better in this respect as I have found a few with their flowers in fairly good shape. But the flower damage doesn’t seem to affect in the least the plant’s capacity to set seed and produce plenty of seed pods.

It seems the humidity of the soil or orchid media dictates whether this orchid can colonize a spot. In one of my relative’s garden the Spathoglottis seedling appear only in well watered orchid pots and in regularly watered flower beds. The rest of the garden remains free of their presence even in areas where one would have thought at first sight that they could do well.