Where have all the wild orchids gone?
A recent study finds that about one quarter of native New England wildflower species have been lost in the last 150 years. This means that purple-fringed orchids and pink lady slippers — once abundant in the region — are disappearing from some areas, often replaced by non-native species. Researchers worry that this loss of biodiversity may harm local ecosystems.
"Wildflowers are an important part of biological diversity; they’re an important part of the environment," says Boston University biology professor Richard Primack, who co-authored the study in the journal Rhodora. "They provide us with clean water, clean air, they also support pollinators which also pollinate our crops."
Researchers used botanical records from the 1800s documenting wildflowers at 13 different locations in New England and New York, and compared them to current wildflower observations. They found that native New England wildflower families — like lilies and orchids — are disappearing, while invasive species like purple loosestrife are moving in. (And Massachusetts' state flower, the mayflower? Once abundant around Concord, these pale pink or white flowers are now hard to find, says Primack.)
Biologist Caitlin McDonough MacKenzie, lead author on the study, said the losses didn't follow an obvious pattern.
“It’s not just developed sites that are losing more of their historic floras," says McDonough MacKenzie, a postdoctoral fellow at the University of Maine. "There are a lot of stressors and threats to our native plants."
For example, the area around Worcester has lost 20% of its native flora, according to the study. And the protected Middlesex Fells Reservation lost 28% of native wildflower species.
Primack says several factors affect wildflower populations, including urban development, increasing deer and invasive plants, pollution and climate change.
“Climate change is not something that is happening in the future, it’s something that is happening right now,” Primack says. “[This study is] an indicator of how successfully species will adapt to climate change, which species will be winners and which ones will be losers.”
The losers, according to Primack, may be New England native species that are more accustomed to colder climates. Climate change is causing the region to experience warmer temperatures earlier in the spring; some native species of wildflowers may not have been able to adapt.
Using Historical Records
New England is a unique place for a study of this kind, according to Primack. Enthusiasm for amateur botany in the 19th century, and general interest in outdoor fieldwork at the time, led to a bounty of botanical records that scientists can reference today.
This particular study was partly possible because two Harvard students — Edward Rand and John Redfield — spent the summer of 1894 documenting wildflowers at Mount Desert Island in Maine. McDonough MacKenzie used their records in her current study, but said it was no easy task translating 19th century records into modern terms.
“It’s really hard to compare different historic data sets to each other,” she says. “And you’re kind of just stuck with whatever survived in the archives.”
During her research, McDonough MacKenzie found that surviving records were compiled mainly by white men at the time. But she’s found evidence that female botanist Annie Sawyer Downs was doing similar work, and believes there were other women and people of color doing botany work at the time.
“There are lots of people that were recognizing plants around them and keeping stock of them. It’s just not how western science collects data and so they kind of get erased or drowned out from the rest of the conversation,” McDonough MacKenzie says. “When we talk about historical floras we have the data sets from certain people but we recognize there’s a lot of missing data out there as well.”
Pollinators, animals and people depend on local wildflowers as the foundation of local food webs. The impact of wildflower losses isn’t clear yet, says Michael Piantedosi, a botanist and seed bank coordinator at Native Plant Trust, who was not involved with the current study. But he says these losses will cause a ripple effect in local biodiversity.
“We don’t actually know the impact losing one species has on a whole ecosystem; it’s with that in mind that we try to protect all of them that are known to be declining or rare in the region,” Piantedosi says. “If we don’t maintain the plants of New England, we lose many other things that are reliant on the plants.”
Piantedosi calls people today "plant blind." To have a better conversation about plant conservation, people need to become more aware of the ecology around them, Piantedosi says. In other words, they need to stop and smell the flowers.
A recent biodiversity report from the United Nations detailed massive extinctions happening across the globe. Even though McDonough MacKenzie's study didn't find that wildflowers have gone extinct, she says the changes she found are just as concerning.
“It can be really hard to wrap your head around these really big, abstract concepts of something like a United Nations report. But when we look at it at a local level it drives home how real this is, especially when you can point to these things happening basically in our backyard here, in New England,” she says. “This is not just a study of something that’s happening to polar bears in the Arctic or the Amazon rain forest being chopped down, this is happening right here.”