120 Years of Botany, Discovery, and Surveying at AMC’s Three Mile Island Camp

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AMC LIBRARY AND ARCHIVESThe main lodge at Three Mile Island Camp on Lake Winnepesaukee in 1903, two years after a pair of botanists collected plant samples that would serve conservation efforts for decades to come.


First-time visitors to AMC’s Three Mile Island Camp often find themselves falling in love with the 121-year-old volunteer-led getaway on Lake Winnepesaukee in New Hampshire. Stepping off the boat at the 43-acre camp, visitors find a shoreline dotted with two-person cabins, each with its own dock. Campers eat together on the porch of the main lodge, relax together in a 1,100-square-foot recreation hall, and enjoy the lakefront from the main dock. The island is interlaced with trails that lead campers along the shoreline and the center ridgeline of the island.

This trail system gives campers a front-row seat to one of the island’s most beloved features: its flora. Nearly every summer since AMC members began camping on Three Mile Island, pointing out the plants and trees and their growth over time has become a favorite tradition.

“There were a lot of birches at Three Mile [Island]. Now there are very few,” remembers Dr. Marjorie Holland, a botanist and longtime camper. “That is just natural succession. Being in New England and having an open area… Some of the hardwoods are going to move in. And then the birches disappear.”

Holland also knows what many visitors don’t: The island’s unique plant biodiversity, and indeed its very sustainability today, is rooted in the work of botanists and AMC members who first visited the island 120 years ago. Since then, generations of community scientists have tracked the island’s botany and worked to steward its biodiversity.


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AMC LIBRARY AND ARCHIVESBirch trees growing on Three Mile Island in 1901.

Sustainability and Change on a Small Island

In 1901, one of the first AMC groups to visit Three Mile Island Camp included a young man named Robert A. Ware. Ware, a botanist at Harvard University, gathered specimens of the plants his fellow campers discovered, cataloguing and preserving them for later scientists to study. Ware was joined by Stanley Pease, a professor of classics at Harvard and a respected botanist who’d later write a treatise on the flora of northern New Hampshire.

Ware and Pease were not working on their own: from the start, they collaborated with other botanists, including several women. Pease’s 1911 paper mentions a Miss M.A. Coe who also participated in the collection work. While we do not know as much about Coe as we do about Ware and Pease—who later served as officers of the New England Botanic Society—we can surmise that she was likely an AMC member as well.

And while most of the specimens originally collected on Three Mile Island eventually became part of the collection at Harvard University, it was a group of ferns at Smith College in Northampton, Mass., that caught the eye of Holland when she was a young graduate student of ecology. While looking at some plants taken from plots along the Connecticut River, Holland—who’d previously been a Three Mile Island croo member—came across several ferns labelled, “Flora of Robert A. Ware collected at Three Mile Island Camp, N.H.”

Holland did a double take, as she was by then a member of the Three Mile Island Committee, the group of volunteers responsible for the island’s maintenance and governance. “I ran into my adviser’s office—also a longtime AMC member—and he told me that the ferns had been given to Smith, while the rest of the plants are all at Harvard,” she recalls.

This chance discovery by a trailblazing scientist soon led to further research that would have a powerful impact on a beloved camp that was then and is still now maintained by AMC volunteers.


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AMC LIBRARY AND ARCHIVESVisitors to Three Mile Island (ca. 1903) wait on the dock for the boat that will ferry them back to the mainland.

Land Use Planning for Sustainability

Around the time of Holland’s discovery at Smith, she was also collaborating with former Three Mile Island Camp croo members Paul Ritch and Jay Maciejowski to create a land use plan inspired by the groundbreaking work of Eugene Odum, a longtime professor of ecology at the University of Georgia. Sometimes called the “Father of Modern Ecology,” Odum had devised a theory that humans need to use land for different purposes, and that setting land aside for those purposes allows other spaces to be kept as protected zones where flora can flourish largely undisturbed.

Maciejowski, Holland, and Ritch came to understand that land use could be categorized and defined in ways that allow humans to coexist with nature. In Odum’s theory, so-called “urban” zones are where people work, get most of their sustenance, and spend a large part of their time; “compromise” zones describe the places where people live; and “productive zones” are spaces for forestry or agriculture. “Protective zones” mark spaces where biodiversity is protected from human intervention. But as Holland noted, these protective zones protect more than plants: “They also support the human spirit.”

In 1972, Holland, Maciejowski, and Ritch applied Odom’s framework to devise a land use plan for Three Mile Island camp in order to better sustain the camp as a whole. The plan was put into place to guide development and preservation by the island’s volunteer leadership, helping them decide where to locate outhouses and new buildings, and which areas of the island to leave undisturbed.


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DIANA JOLLESThe volunteer sampling team identifies plant species growing inside a white quadrat at Hawk’s Nest Island in June 2021. From left to right: Glenn Ritch, Senna Stoughton, Anna Donnelly, Tommy Stoughton (standing), Cole McShane, and Marge Holland.

A Study to Track the Land Use Plan

Once the land use plan had been developed, however, AMC leadership had an important question for the plan’s architects: how would they know it was working? Inspired by the 70-year-old specimens Holland had discovered in the Smith herbarium, the young scientist had an idea: Track biodiversity over time with a botany survey that would continue the work begun by Ware and Pease years before. Maciejowski, a forester, and Holland, by then a professor of plant ecology, contacted Bill “Bat” Clapham, a plant physiologist. The botany trio began working on a methodology to sample island plants and assess the impact of the camp’s land use plan.

Research began during the summer of 1978. From the start, the study drew on Three Mile Island croo and volunteers, just as Ware had relied on his fellow visitors in 1901. The croo picked numbers out of a hat correlating to possible plots across Three Mile, Hawk’s Nest, and Blueberry Islands. The croo selected 25 permanent plots that have been sampled ever since: 19 on Three Mile, three on Hawk’s Nest, and three on Blueberry Island. Clapham, Maciejowski, and Holland sampled the Three Mile Island plots during summer 1978, and Holland led a team of volunteers to conduct sampling on Hawk’s Nest and Blueberry Island in 1979.

After the initial sampling in 1978 and 1979, Holland realized that she needed to check name changes of plant specimens over time. Holland enlisted Bruce Sorrie, of the Massachusetts Natural Heritage and Endangered Species Program and member of the New England Botanical Club, and the two found 66 plant species were not included in the original surveys.

Roughly every 10 years between the late 1970s and 2011, Holland led a team to analyze these plots, following in the footsteps of the earliest AMC visitors to the island. Holland has since published and presented her research at numerous scientific meetings.

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ANNA DONNELLYDr. Marjorie (Marge) Holland smiles as the sampling team moves from analyzing ground cover to measuring canopy cover at Three Mile Island Camp in June 2021.

Passing the Torch: A New Generation of Botanists and Community Scientists

Few locations in New England can boast 120 years of plant sampling that demonstrates how the forest has developed. A number of years ago, Three Mile Island’s leadership began searching for a botanist who could work alongside Holland and continue the study into the future. As Holland puts it, “with Bat [Clapham], Jay [Maciejowski], and I all retired, it was time to pass the data.”

When Three Mile Island’s leadership contacted Dr. Diana Jolles of Plymouth State University about joining the long-term study, she immediately recognized its value.

“These long-term ecological studies are really valuable and really rare,” Jolles says. “If you get to be involved with one— it’s like the Holy Grail. It’s very good luck to be in the right place at the right time to take on work that has been passed from scientist to scientist. I feel honored.”

In June 2021 Holland, now retired, worked side-by-side with Jolles to relocate the plots, implement the sampling protocols, and officially pass along her data to a younger botanical generation. Jolles’ base at Plymouth State University in New Hampshire opens numerous doors for students and faculty to undertake the current long-term study and conduct related botanical and ecological studies.

As Drs. Holland and Jolles collaborated this June on the botany collection process, they relied on the experience of Three Mile Island volunteers, many of whom have worked alongside Holland for years. One volunteer, long-time Three Mile camper Betsy Atkins, has attended the camp since she was a child. Tersh Palmer, an English professor at Castleton University in Vermont, has also assisted the effort. These community scientists are not professional botanists, but rather hobbyists who are generally self-taught and extremely knowledgeable. As Jolles notes, “Amateur botanists are highly valued in our community.”

The specimens collected by Ware, Pease, Coe, and others in 1901—and years later discovered again by Holland in the Smith herbarium—provide a historical glimpse into the island flora at the time. But the main point of the study is not just to list the plants, but rather provide evidence that the 1972 land use plan Holland, Maciejowski, and Ritch developed is working as it should today. The survey tracks both the frequency of any particular species in the 25 plots as well as the density of trees and amount of space that each tree occupies in the canopy.

Because of the data collected during the botany survey, volunteers and visitors to the island can appreciate the land use plan and the role of the botany study in the development and preservation of the island. One of the findings of the study is that plant diversity has increased over time on the island. Biodiversity has long been seen by scientists as a marker of ecological health, and it is decreasing worldwide because of development and climate change. According to the data the botanists have collected each decade, the land use plan is unfolding just as its developers had hoped. Each decade, they have been able to track and monitor the vegetation in each of the plots they established half a century ago.

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RACHEL GARCIAThe sampling team celebrates the completion of data collection in 10 long-term sampling plots at Three Mile Island and three sampling plots at Blueberry Island. Front row: Abby Clapham, Bill Clapham, Dr. Marge Holland, and Karli Cowman; Back row: Cole McShane, Diana Jolles, Senna Stoughton, Tommy Stoughton, Betsy Atkins, Tersh Palmer, and Anna Donnelly.

Women Botanists and Cross Pollination 

To see Drs. Holland and Jolles working together is to see two generations of women scientists collaborating in the service of a project that has both served the AMC community and inseparably linked their careers. Holland was a trailblazer, as one of the first women on the Three Mile Island committee and the first woman professor of biology at Amherst College in Massachusetts. Later she became a full professor in the department of biology at the University of Mississippi at a time when fewer women attained that status. She sees herself following in the footsteps of Ware and Pease, but also amplifying the work of the lesser-known women botanists who came before her—Coe among them. She knows that the botany study would not have been possible without many volunteer hands. Community Science is a way of life on Three Mile Island.

Jolles is a trailblazer herself. She has long studied the role of pollinators—the birds and bugs who help plants to grow by moving pollen between them. She sees the Three Mile Island botany study as an opportunity for other kinds of cross-pollination—such as between AMC, volunteer community scientists, university undergraduates, and future generations of campers. Future visitors will not only have the opportunity to enjoy the island’s biodiversity, but perhaps even join in a future study themselves, the researchers say.

The 2021 sampling included undergraduate students working as field partners alongside Holland, Jolles, and longtime campers. The opportunity for one-on-one mentorship is invaluable for first-year science students, as it could very well set them on a course of their own lifetime of study.

“This is a good transition research opportunity for young scientists wishing to develop sampling skills and understand experimental design,” Jolles says.

Now, both scientists are working in collaboration with the island’s staff to develop plans for educating people about the island. For example, Holland helped to re-invigorate interest in a tree trail on the island, engaging 2019 AMC croo members who had taken some dendrology and biology courses. Following the plant study in 2021, Jolles will return to the island during the summer of 2022 to provide educational walks on the island, as part of an approach to environmental education for adult and child visitors.

The data volunteers have collected since 1978 can serve as a baseline against which future change can continue to be monitored and managed, Holland says. “Now, we have data,” she says. “We can be a test study to compare with sites on the mainland. We can make management decisions based on science.” In part because of the evidence this study has provided, The Three Mile Island Camp Committee keeps expanding the area in the protective zone, understanding its value to the camp as a whole. With the help of AMC members past and present, Holland and Jolles have established a dialogue about the island’s ecology, its future, and about the plans and processes that will keep it a haven for plants, and people, for generations to come.

About the Author…

Launa Schweizer

Launa Schweizer, an educator and writer living in New York City, has served on the Committee of AMC Three Mile Island Camp in New Hampshire.

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