Ghost Pipes: A Lesson In Connections
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If you’ve read very many of our posts on plants and animals, you’ve likely noticed we approach everything at Harmony Hill in a holistic manner. We look at how things are connected in nature, and we deeply appreciate the relationships we see between the flora and fauna found here. That holistic approach extends to the garden and even how we manage the forests of Harmony Hill. John Muir once said, “When we try to pick out anything by itself, we find it hitched to everything else in the universe.” And we try to spotlight just how things are hitched together in our visits with you during these posts. Today, we look at how a unique flower, fungi and trees are hitched to each other. And as is our hope with each story of the land we tell, we hope you carry that appreciation of the connections that are ever-present in nature.
When the hottest days of summer are winding down, walks in the woods become longer and we linger more in moments of discovery. In those moments, our eyes wander to find colors other than the greens, blues, yellows, and purples of the usual wildflowers this time of year. Every now and then, when we’re lucky enough to be in the right place at the right time, we find one of the rarer wildflowers of Harmony Hill. This flower is rare in blooming frequency here and it is rare in its life cycle. A true flower that looks more like a fungus. A true flower that, in fact, parasitizes mycorrhizal fungi to get nutrients and even water that the fungi are sharing in a symbiotic relationship with the roots of trees!
Ghost Pipe (Monotropa uniflora) is, to say the least, a curious looking plant. And, make no mistake, it is a plant. As much as it may look as though it should be classified as a fungus, it is every bit a flowering plant! With its ghostly white color, often accented with a tinge of light pink or pale red, its waxy flower, and its scaly leaves, it could easily win a plant costume contest for best impersonation of a fungus. It is so good at this that even scientists considered it a weird fungus for many years. However, the stem, the flower, the leaves, the pollen, and the roots prove it to be a true wildflower.
The oddities of Ghost Pipe don’t end with its zombie-like appearance, which is due to its complete lack of chlorophyll. Would you believe this plant is in the Heath Family (Ericaceae)? That’s right! It is a direct relative of heathers, blueberries, sparkleberry, and azaleas! Remember when we talked about Swamp Azaleas found at Harmony Hill? This little 5” parasitic plant is in the same family!
Now that we know this is a flowering plant and that it is a parasite, lacking chlorophyl, let’s look at how Ghost Pipe gets nutrients and how it reproduces.
To begin to tell that story, we must step away from Ghost Pipe for a little while and look at trees, their roots, and the relationship those roots have with mycorrhizal fungi.
There are fungi that weave into the root systems of trees to form a symbiotic relationship between the two organisms. The fungi and the trees are in a mutualistic relationship, in which both organisms benefit from the relationship. The trees provide the fungi with carbohydrates and nutrients, while the fungi increase the surface area and absorption rate of the trees’ roots and provide the tree with greater access to water and nutrient uptake from the soil.
It is a win-win for both parties and this mutualistic relationship spreads far and wide underneath the surface of the forest. That’s where Ghost Pipes come in to take advantage of this connectivity.
In a stroke of genius evolution, Ghost Pipes weave their roots into the mycorrhizal fungi and convince the fungi it is an active member of the same mutualistic relationship we just described. Instead of mutualism, Ghost Pipes establish a parasitic relationship with the fungi, which are working with tree roots. In essence, the Ghost Pipes are using the fungi to parasitize nutrients from trees! There are some hypotheses which seem to point to some sort of chemical signal in the Ghost Pipe roots that even prevent the fungi and trees from recognizing they’re being used, preventing them from growing galls or resisting the parasitic organism.
In fact, the vast majority of the life cycle of this cool plant is spent underground, taking advantage of the nutrients being syphoned from the tree roots and mycorrhizal fungi. This can go on for years! When the right conditions arise, the right combination of dry weather followed by wet weather, which we still don’t have a full understanding, the plant will send its stem up to hold a solitary flower. For just 5-7 days, the Ghost Pipe will show the world above ground its beauty.
As with so many other flowers, pollinators will come to visit the plant. Bumblebees, along with a few species of flies and other bees, are the most common visitors to the flowers of Ghost Pipe.
After pollination, extremely small seeds develop, and the flower of the Ghost Pipe will turn from facing the ground to standing straight up. Those seeds will eventually be released to the wind and the cycle will begin again.
Remember those chemical signals we said the plant likely uses to convince fungi that it is part of the mutualistic relationship with a tree? The same chemical signals are believed to be used by the seeds of Ghost Pipe as it waits until it can come into contact with an appropriate fungal host.
Let’s look back at that scientific name, Monotropa uniflora. It translates to “a single flower with one turn”. The one flower that blooms has one curve on the stem that makes it look like a pipe! With the pale white overall color of the plant, there is no wonder as to where the common name of “Ghost Pipe” comes from.
Native Americans were said to have used this plant as a pain relief medicine for everything from headaches to toothaches. Making tinctures from this plant, early settlers were also said to utilize this plant as a way to lower pain. It was said the key to making the tincture was to harvest the tiny plant while the flower was still turned down.
With a range covering much of North America, seeing Ghost Pipe for yourself is very possible. You just have to be in the right place at the right time. If you’re lucky enough to see it, take a few moments to celebrate the chemical trickery that allows a parasite to sneak into a mutualistic relationship, then grow into a flowering plant that looks exactly like a fungus. And remember why Harmony Hill looks at each habitat with a wide lens. Our view of the world is framed by the connections in nature and by the words Muir so eloquently said, “When we try to pick out anything by itself, we find it hitched to everything else in the universe.” This is yet another example of that… a ghostly white flower sitting just a few inches above the ground reveals connections far beyond the scope of the postage stamp size ground it occupies.