A short way down a path in Arcadia Wildlife Management Area in Exeter, Hope Leeson strolled into a dry overgrown
meadow in search of a rare orchid called spring ladies’-tresses. The species is
known from just three sites in Rhode Island, and when this particular
population was checked last, there were just 25 plants growing there.
After wandering around for 10
minutes, she stumbled upon a single foot-tall specimen. A short time later, she
found a patch of seven more hidden from view by tall vegetation. Each featured
tiny white flowers spiraling around the top of the stalk.
“The flowers spiral like that to
better present themselves to their pollinators,” said Leeson, a botanist for
the Rhode Island Natural History Survey. “But they’re getting lost in all these
other plants.”
Despite searching the one-acre site
for another 20 minutes, Leeson found no more orchids. Her experience was not
unexpected.
Spring ladies’-tresses is one of 40
kinds of orchids found in Rhode Island and one of 34
that are on the state’s list of rare species. Many appear to be declining in number, based on
recent
efforts to find them, and nine of them have not been seen for so long that they
are considered historic.
that are on the state’s list of rare species. Many appear to be declining in number, based on
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| Spring ladies'-tressses (Todd McLeish) |
“Rhode Island’s orchid populations
seem to be shrinking,” said Doug McGrady, an amateur botanist who spends all of
his free time wandering the state in search of rare plants. He was the last
person to report on the Arcadia population of spring ladies’-tresses in 2017.
“In other states, orchids are more plentiful and you might find hundreds of
them in a patch. But when you find a patch here, ours are always smaller. And
it doesn’t always seem like there’s a logical explanation why.”
According to Leeson, orchids are
rare for numerous reasons. Many species have very narrow habitat requirements.
They also require a particular kind of fungal community in the soil in order for
their seeds to germinate and for the plants to gather nutrients, and that
fungal
community is unique to each species. If the soil gets disturbed, the
fungal community can become disrupted. Many orchids also produce only one
flower, so their chances of reproducing are minimized.
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| Small purple-fringed orchid (Todd McLeish) |
The plants are also rare due to
habitat loss and because deer eat them before they have a chance to produce
seeds for the next generation. And the changing environmental conditions due to
the climate crisis is likely having an effect as well.
“In looking through the records of
the orchids that bloom this month, a lot of those recorded in the 20th
century haven’t been found recently because the habitats have been lost,”
Leeson said. “They’re now housing developments and gravel pits. Humans have
moved in.”
Little is being done to conserve the
many rare orchids in Rhode Island.
“We do not currently have a dedicated formal
effort to monitor or sustain orchids,” said
Tanner Steeves, a wildlife
biologist with the Rhode Island Department of Environmental Management, in an
email. “However, we certainly attempt to care for, and perhaps more
importantly, avoid negative impacts to orchids where we are aware of them on
DEM land under our Division’s supervision…Going forward we are planning to
submit a State Wildlife Grant proposal to fund pollinator-related management in
the absence of state funding. This grant may cover management activities
devoted specifically towards benefiting rare plants, including orchids, due
their importance for supporting insect biodiversity.”
 |
| White-fringed orchid (Todd McLeish) |
The rarity of orchids – along with
their intricate floral structure – is one reason why many people are so
enamored of them.
“There is something magical about
them that makes people nuts,” said McGrady. “I like them in part because other
people think they’re precious. And I like that they’re something unusual and
they’re usually attractive.”
Leeson continued down the path at
Arcadia for about a half mile, then walked a short distance along the edge of a
muddy stream in search of a population of small purple-fringed orchids, another
rare species known in Rhode Island from just nine sites in the West Bay.
Pollinated by small butterflies called skippers, the beautiful plant displays
showy purple or magenta flowers with fringed petals.
She found just one plant where
McGrady observed five – four of which had been eaten by deer – in 2011.
But just 12 feet away from the
solitary small purple-fringed orchid, Leeson discovered a group of five green
woodland orchids, a variety added to the state’s rare species list in 2016 and one
that had not previously been observed at the site. It’s a species she had only
seen once before in Rhode Island, along a woodland stream in Westerly.
Earlier that day, at the Great Swamp Management Area in South Kingstown, Leeson located a population of more than
100 white-fringed orchids, a showy species found at four sites in the state.
Growing up to three feet tall, it prefers open habitat to attract pollinators
to what Leeson called its “landing pad,” the bottom petal where night-flying
moths land seeking nectar.
Despite the somewhat large
population, Leeson is concerned that the surrounding vegetation was growing so
tall that it would soon crowd out the orchids, just like what appeared to be
happening at the site of the spring ladies’-tresses in Arcadia. At both sites,
Leeson said, the orchids would benefit from the clearing away of some of the
larger vegetation.
“There is this great allure of
finding orchids and the beauty of them, but we don’t really understand much
about their ecology – how they fit into their habitat, what their role is and
the role of the other plants in the community, and about the fungal community
specific to each habitat,” she said.
Leeson and McGrady are volunteers
with the New England Plant Conservation Corps, managed by the Native PlantTrust (formerly the New England Wild Flower Society) in Framingham, Mass.,
which dispatches plant enthusiasts to check up on rare plant populations
throughout the region. They count individual plants, record their stage of
growth and other species growing with it, and note any invasive species growing
in the vicinity.
“There’s not much happening to
protect orchids in Rhode Island, other than the volunteer work monitoring where
they’re located,” Leeson said. “Orchids are difficult to propagate, but the
Native Plant Trust is working to propagate rare orchids so they can be used to
augment populations if necessary. But it’s a steep learning curve.
“The best places to find orchids are
in large forested tracts, especially large forests with a mosaic of bogs and
wet meadows and woodlands,” she added. “So the best thing we can do to protect
orchids is to place a greater emphasis on the protection of large forested
areas.”
This article first appeared on EcoRI.org on August 8, 2019.
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