Orchids: The Smartest Plants in the World
It’s a cold winter day, and I’m exploring an old forest of oaks, tulip poplars and beech trees in Anne Arundel County, Maryland.
I’m with Dennis Whigham, an ecologist at the Smithsonian Environmental Research Center, hunting for orchids. Many of the 25,000 known species of these flowers are threatened or endangered, in part because their complex lifecycle is vulnerable to disruptions caused by development.
So Whigham and his colleagues are trying to save these dinosaur-era plants. Now, you might find it odd that we would be out looking for plants in the dead of winter. But soon we find purple-spotted leaves erupting from a rotting log. These crain-fly orchids only grow their leaves when the plants around them are bare.
“What’s interesting about this orchid is that it is what you call wintergreen,” said Whigham. “If you were to come here in the summer, you wouldn’t see this plant. It has no leaves. And we think that’s because this forest is very shady in the summer. And so if you are an orchid, it might not be a bad idea to have your leaf out whenever there aren’t a lot of leaves on the trees, because you get more sunlight.”
It is this ability to outwit other life forms that makes orchids what Whigham calls the smartest plants in the world. Other orchids fool insects into trying to mate with them by making their flowers look like the opposite sex. Or they attract flies to spread pollen by exuding the perfume of rotting meat.
Whigham explains that the life of these beautifully clever plants is dependent on death. The roots of orchids draw their nutrients from fungus, which consume dead and rotting plant matter.
We hike back to his lab at the Smithsonian Environmental Research Center in Edgewater.
“There are threatened and endangered orchids in every state in the country, in every province of Canada,” Whigham said. “And in fact one of our research projects is focused on the most endangered plant in Eastern north America, which happens to be an orchid… It’s called the Small Whorled Pogonia.”
These orchids look like green pinwheels with dragon head flowers, and they are extinct in Maryland. One of Whigham’s colleagues, Jay O’Neill, shows me a glass vial holding their tiny, hairlike seeds. Whigham’s team is trying to bring them back, as scientists might try to hatch dinosaur eggs in a science fiction movie.
The researchers are using this machinery to analyze the DNA of the orchid roots, to figure out which orchids need to draw nutrients from which fungi. They have tried everything to try to get the pogonia seeds to germinate – bathing them with sugars, vitamins, hormones, even bleach.
But they can’t yet get the seeds to grow, because they can’t get a particular kind of red-capped mushroom fungi to grow.
His theory is that disturbance of old-growth woodlands – either through suburban development, logging or invasive species – disrupts fungal communities in the soil in ways that might take decades to heal. Without the right mix of fungi and tree roots, orchids can’t live. Cutting down forests may trigger a cascade of subtle problems that people do not even see – or think about for generations.
It’s an interdependence that runs like a spinal cord through nature.
The Environment in Focus is independently owned and distributed by Environment in Focus Radio to WYPR and other stations. The program is sponsored by the Abell Foundation. The views expressed are solely Tom Pelton's. You can contact him at [email protected]