Furbish’s Lousewort: A Species on the Edge
FURBISH’S LOUSEWORT: A SPECIES ON THE EDGE
WRITTEN BY ASH NOBLE, COMMUNICATIONS OFFICER
When I started my internship in the communications department at the Nature Trust, I did not expect to be wading through the Wolastoq/St. John River and scouring its banks in search of a small, endangered plant with a strange name.
With the threat of rain looming overhead, keeping my balance on the riverbed’s rocky bottom while simultaneously combing through thick alder looking for those trademark, fern-like leaves became a matter of urgency. One wrong step, and I risked bringing an entire species that much closer to extinction.
A Furbish’s lousewort (Pedicularis furbishae) plant grown from seed
We were searching for Furbish’s lousewort, or Pedicularis furbishae, a perennial plant that only grows along the banks of the Wolastoq in northwestern New Brunswick and northern Maine. It has not been documented anywhere else in the world.
Furbish’s lousewort was first discovered in 1880 by Catherine (Kate) Furbish, a Maine botanist who dedicated her life to exploring the natural world. While thought odd and unconventional at the time, Furbish made countless significant contributions in her lifetime, donating more than four thousand plant specimens to Harvard University’s Gray Herbarium and sixteen large folios of botanical drawings to Bowdoin College.
Reflecting on her life’s work, she wrote to Bowdoin’s president, saying “I have wandered alone for the most part, on the highways and in the hedges, on foot, in hayracks, on country mail-stages, on improvised rafts, in rowboats, on logs, crawling on hands and knees on the surface of bogs, and backing out, when I dared not walk, in order to procure a coveted treasure. Called ‘crazy,’ a ‘fool’ – and this is the way that my work has been done, the flowers being my only society, and the manuals the only literature for months altogether.”
Across the border, local conservation heroes Dr. George Stirrett and Fred Tribe discovered new sites of Furbish’s lousewort in 1977. They initiated the first conservation efforts for the species in New Brunswick and were the driving force behind the formal recognition of its endangered status in Canada in 1980.
Realizing the importance of conserving this rare species, the Nature Trust established the George M. Stirrett Nature Preserve in 1992 to protect one of the five known sites of Furbish’s lousewort in New Brunswick. Since then, our dedicated volunteers and staff have spent countless hours monitoring and protecting this riverbank habitat and the lousewort that call it home.
Sally McIntosh, one of our lead volunteers at the preserve, has fond memories of her first survey at Stirrett. “It was thrilling to find such a critically-endangered species,” she says. “To be looking at something so rare was truly a privilege. It is unnerving to be searching through the thick foliage, fearful of treading on one of the last remaining plants of this species. You must carefully watch exactly where you place each foot.”
After spending a day scouring the banks of the Wolastoq myself, I can understand this mix of excitement and fear.
In July of 2023, I joined Graham Forbes, a professor and faculty director at the University of New Brunswick (UNB), provincial biologists Shaylyn Wallace and Parise Ouellette, and Canadian Forest Service (CFS) representatives Martin Williams and Chantelle Kostanowicz as they surveyed all existing sites of Furbish’s lousewort in New Brunswick.
Together, they transformed this strange, little plant that I’d only read about in reports into something real. I got to see its fuzzy, fern-like leaves up close for the first time, to observe it in all stages of its life and in a variety of unique riverside habitats. It was inspiring to work alongside a group of such dedicated individuals, to be a fly on the wall as they discussed next steps for the plant’s recovery and reminisced on their work over the years.
You see, after reading reports and hearing stories about Furbish’s lousewort, I thought I had a good understanding of its current state of recovery. Only after seeing the sites myself did I realize how dire the situation really was.
Despite the exceptional dedication of people like Sally and my fieldwork companions over the years, the provincial population of Furbish’s lousewort has declined by 71 per cent since 2002.
Mature Furbish’s lousewort plants hanging on the edge of the Grand Falls bank
You probably won’t be surprised to learn the primary culprit is climate change.
Furbish’s lousewort habitats are becoming unsuitable due to excessive erosion, severe flooding and ice scouring, and competition from other plants. While periodic flooding and scouring are necessary for creating and maintaining its habitat, climate change is making these processes more severe and destructive, chipping away at the lousewort’s natural habitat at an alarming rate.
The Nature Trust has partnered with organizations such as the provincial government’s Department of Natural Resources (DNR), CFS, and UNB to help monitor Furbish’s lousewort and study the cause of its continued decline.
Graham Forbes, who is also Director of the New Brunswick Cooperative Fish & Wildlife Research Centre, refers to Furbish’s lousewort as ‘the Goldilocks species.’
“The conditions need to be just right for the plant to grow and survive,” he said as we made our way toward one of the sites in 2023.
Viable habitats along the Wolastoq must maintain a perfect balance of flooding and ice scouring, forest cover and riverbank, wet and dry soil, and shade and exposure. Too much or not enough of either, Forbes said, and the whole system falls apart.
In the last decade, the conditions have been anything but ‘just right.’ “You know things are bad when you can’t rely on the site to do its job [and sustain plant growth]” Forbes said. Recognizing this, the Furbish’s lousewort recovery group is working to find solutions and strategies to ensure its survival.
In 2006, the provincial government set a goal to maintain at least 200-250 plants per subpopulation. Over the four subpopulation sites we visited in July of 2023, we only counted around 264 plants in total, of which 168 were found at the Grand Falls site alone.
As we drove from site to site conducting these plant counts, my companions reflected on how much had changed since they first started working to protect this species. Where vast banks of Furbish’s lousewort once grew, jagged edges of earth, eroded shores, and floods of water remain. Wading through the Wolastoq to reach our Grand Falls site, I got to see the results of these threats firsthand.
Searching the shoreline, we found a group of three mature plants nestled together. They were hanging on the edge of the bank, vulnerable to any rogue flood or chunk of ice that should cross their path. As the shoreline erodes more and more each year, these plants will be lost first.
As I watched them sway in the breeze, clinging to the edge of the rugged bank, I thought about how perfectly they encapsulate the urgency and importance of Furbish’s lousewort recovery.
If we do not protect this plant, the population will decline until an entire species is washed away, lost to the river that was its only home. By working to conserve Furbish’s lousewort now, we will be saving a piece of history and natural intrigue for future generations.
“We have an ethical responsibility to protect Furbish’s lousewort,” Forbes said. “Without our help, the species won’t survive.”
As we moved to the next site, I’m reminded of an excerpt from an article I’d read while researching this strange plant:
Our Nature Trust team helping plant new Furbish’s lousewort plants at our George M. Stirrett Nature Preserve
At a hearing on the Dickey-Lincoln School Dam in the late 1970s, a Maine congressman asked a colonel in the Army Corps of Engineers, “What is the function of the lousewort? Does anybody need it?” “Sir,” the colonel replied, “I can only suppose that it is part of the grand scheme of things.”
The future of Furbish’s lousewort may be uncertain and daunting, but there have been some promising developments in recent years.
Two seeding sites, or field banks, are successfully growing lousewort and providing secure habitats for plants whose ‘wild’ habitat was clearly too precarious and threatened for them to survive. The researchers tell me that this ex situ—protecting a species outside of its natural habitat—conservation strategy is labour intensive and time consuming but is worth it to ensure the species' survival.
Two years later, we have seen first-hand how these efforts to grow lousewort plants in secure field banks and seeding sites can help restore native habitats of Furbish’s lousewort.
On June 26, 2025, our Stewardship team joined CFS and DNR to plant 72 new Furbish’s lousewort and their host plants, grown by Williams in a greenhouse from seeds, at our George M. Stirrett Nature Preserve where they will be forever protected in their natural habitat.
CFS will monitor the newly planted plots monthly to assess the health and success of the population and guide future planting and recovery efforts in New Brunswick, which are outlined in DNR’s 2025 draft Recovery Strategy for the plant.
This recovery strategy outlines plans to support Furbish’s lousewort by reinforcing existing populations and establishing new ones across its native range. While the strategy is still in development, it signals a commitment to collaborative action—including seed banking, planting efforts, and long-term habitat care—to ensure Furbish’s lousewort can continue to grow in New Brunswick for generations to come. With just 262 plants remaining as of 2025, 98% of which are concentrated in the Grand Falls subpopulation alone, it is imperative that these restoration efforts continue.
Furbish’s lousewort’s strange partiality to the banks of this river is part of what makes it unique, and whenever possible, we want endangered species to grow and thrive in their natural habitats. Conservation of this unique habitat is critical for the species.
If you own land along the Wolastoq and think you may have Furbish’s lousewort on your land, or if you just want to learn more about the natural ecosystem on your land, we’d love to hear from you! Our Conservation Partner Program supports landholders across New Brunswick who want to take care of their property in ways that maintain rare species and the wildlife and plant life that make our province so special.
If you own land with a natural shoreline habitat between Grand Falls and Aroostok and want to help give this rare plant a ‘forever home,’ there may also be an opportunity to be part of the recovery effort and become a new planting site for Furbish’s lousewort. Whether you're curious about planting or simply want to learn what planting on your shoreline might look like, contact our Conservation department or DNR to chat about your options —together, we can help bring this unique piece of New Brunswick’s natural story back to life, one shoreline at a time.
And remember, the next time you find yourself walking along the banks of the Wolastoq, tread lightly—you may stumble upon something extraordinary.