BOOTHBAY — Susan Wall spread glue on a sheet of glass with a paintbrush, then gingerly lifted a stiff, dried plant from inside a 1949 newspaper and placed it on the sticky surface. She glued the plant to a sheet of acid-free, archival paper, fitting it on the page just so, before it was labeled and ready to be filed away at the Coastal Maine Botanical Gardens’ new(ish) herbarium.

The plant was, according to its old label, Hieracium canadens Michx, also known as Canadian hawkweed, and it was collected on Aug. 31, 1949 in the woods of Norway, Maine. Across the table from Wall, Hoyt Walbridge used tweezers to place a specimen of Caryx nigra in just the right spot on another sheet of paper. The sedge was collected in 2014 at Reid State Park. When he was young, Walbridge dreamed of being an archaeologist. “Maybe this is satisfying that need,” he said.

The act of mounting and pressing plants to collect in an herbarium blends a bit of art with a large dose of science. It is, at once, a quaint, old-fashioned hobby and an important scholarly endeavor. It can be a complex task, taking up to 40 minutes to engineer a plant on a page, Wall said, but also “a quiet, meditative thing to do,” which is perhaps what led Henry David Thoreau and Emily Dickinson to build their own herbaria 150 years ago. “It was something a lot of people did – an earlier version of scrapbooking,” Wall said.

Jan John works on filing specimens in the herbarium, which is staffed mostly by volunteers. John travels from her home in Round Pond once a week to help at the herbarium.

Today botanists are still mounting plants the old-fashioned way, but they are also bringing herbaria, including the ones in Maine, into the 21st century. Following a national movement to digitize plant collections, they are putting information from plant labels into online databases, along with photos of the plants. The updating is opening up plant collections to a worldwide audience, from botanists who might want to borrow specimens for an ecological study or DNA analysis to the plant-loving public trying to learn about invasive species or that odd-looking flower growing down the street. Locally, herbarium collections can be invaluable in making conservation decisions. They may also help scientists track the effects of climate change by studying plants’ shifting flowering times or the movement of southern plants northward.

A LIVING LIBRARY

An herbarium is actually a collection of collections. Botanists both living and long dead develop their own personal collections of dried plants from specimens they’ve gathered in the field. Those private collections ultimately are donated and absorbed into public herbariums. Meanwhile, herbariums like the one at Coastal Maine Botanical Gardens get a regular infusion of new plants from researchers and volunteers out collecting in the field. So the herbarium is like a living plant library, constantly adding new material and growing.

Maine has a half-dozen herbariums of note. The University of Maine’s herbarium in Orono is probably the largest, with 50,000 specimens of vascular (higher) plants representing 2,000 species. The collection also includes fungi, algae, mosses, and so many lichens that they have their own room. (The 12,000 lichen specimens include the collection of Steve Selva, a professor at the University of Fort Kent who spent his whole career studying the symbiotic organisms in northern Maine.)

“We don’t know how old it is,” said Christopher Campbell, an emeritus professor at the university who is managing the collection until a new curator arrives in January. “We have specimens that predate the formation of the university.”

It also includes specimens from Merritt L. Fernald, who grew up in Orono (his father was president of the university) and became a world-renowned botanist and professor at Harvard.

Specimens at the Coastal Maine Botanical Gardens’ herbarium that date to the mid-to-late 1800s.

“He left a lot of specimens that he collected as a teenager back in the 1870s and 1880s,” Campbell said, “so it’s an old collection, but it also has been added to pretty consistently over the last 120 years.”

Forty to 50 volunteers help maintain the collection, doing everything from identifying, mounting and filing plants to making new packets to store moss specimens – that last project alone took about a year.

The herbarium, Campbell said, is “of broad importance to the university, and it’s also important to the public because if some kid eats a potentially poisonous mushroom or potentially poisonous berries, they’ve got to know what they’re dealing with. We also identify weeds for farmers.”

Other herbaria can be found at Colby College, the University of Maine at Machias, the University of Maine at Fort Kent and the College of the Atlantic.

A professor started the herbarium at the College of the Atlantic in the mid-1970s, and it now has just shy of 18,000 specimens, according to Geneva Langley, who manages it. Nearly 11,000 of those are vascular plants, and the rest are fungi, mosses, liverworts, lichens and algae. The oldest specimen, from 1894, is a Blake’s aster collected by Edward Rand and John Redfield, who published the first checklist of the flora of Mount Desert Island. But most of the college’s collection dates from the 1960s and later.

The College of the Atlantic Herbarium also relies on volunteers. Even Langely is funded for just seven hours of work per week.

“One of our biggest challenges is finding folks with a taxonomy background to identify some of our unknown plants,” she said.

COLLECTING AND COLLABORATING

The Coastal Maine Botanical Gardens planted the seeds of its herbarium in 2014 with two plant collections. Alison Dibble, who lives in the Blue Hill area, contributed several thousand plants from her personal herbarium, which were combined with several thousand from the personal collection of Melissa Cullina, a research botanist at the gardens who is also acting as curator of the new herbarium. Cullina’s collection includes plants from Massachusetts and the Boothbay region. Since then, plant specimens have been donated from a number of institutions, including the University of New Hampshire, the University of Vermont, the Maine Natural Areas Program, the New England Botanical Club and Bentley University in Massachusetts.

As it’s grown, the herbarium has been given its own space, in two remodeled rooms previously used by the gardens’ education department, including a climate-controlled room (kept at 65 degrees F) filled with cabinets to house the plants. The rooms opened in June, and about 3,000 specimens are either already filed there or are waiting their turn to be mounted. More come in with every field season. When full, the herbarium will have space for 25,000 specimens.

It’s just getting started.

A pitcher plant that was collected in the 1840s or 1850s by Maine botanist Aaron Young Jr. is one of the oldest specimens at the herbarium at Coastal Maine Botanical Gardens.

The herbarium is collaborating with an ongoing research project called Midcoast Flora, an effort to study the complete plant biodiversity of Lincoln and Sagadahoc counties. The botanical gardens is partnering with the Maine Natural Areas Program on the project, with the cooperation of local land trusts that are allowing the collection of plants on their properties.

“What’s interesting is this particular part of Maine, especially those two counties, are very under-represented in other herbaria, and so there’s an important niche for us there,” Cullina said. “The really botanically unusual places, such as the calcareous regions of northern Maine, like the St. John River Valley, Katahdin, Mount Desert Island, those have all received a lot of attention. But this region less so.”

The information that’s gathered will help botantists and land trusts set conservation priorities in the region, Cullina said, “but it’s going to take that deep knowledge and understanding first.”

The collecting is being done by Cullina; Don Cameron, the state botanist; Sherry Holmes, a retired botanist who lives in Wiscasset; Paul Bushmann, a visiting professor from Maryland on sabbatical who is interested in sustainable horticulture; and a team of interns and volunteers.

“One of the things we really need to look at is how the flora has changed, and what new non-native plants have moved into our area,” Cullina said. “That’s a particular area of interest.”

Another is studying what grows on “the very warm area that’s found here on this peninsula,” where ocean temperatures moderate extremely cold days, Cullina said. “We laughingly call this the banana belt of Maine.”

“We’re expecting to find plants you would typically expect to find in more southerly parts of Maine, or even beyond,” Cullina said. “We think that could be interesting as plants are moving northward in a rapidly changing climate. We’re really trying to better understand how extensive the southern component of this flora is here.”

SAME PLANT, SAME PLACE, 100 YEARS LATER

The herbarium is also used to support the botanical gardens’ education program. In August, Bobbi Angell, a well-known botanical illustrator, taught a class called “Drawing from the Herbarium,” in which she showed students how illustrators ensure their drawings are botanically accurate. In “Asters of Coastal Maine,” students relied on the herbarium to learn to identify asters, and to see some varieties they probably wouldn’t encounter in a walk in the local woods.

The gardens’ herbarium contains specimens dating from the 1840s to the present day, some 80 percent from Maine. The collectors represented include Edward B. Chamberlain, a botanist who had a home in the Bristol area; Albion Hodgkin, who grew up in Boothbay; and Norman Fassett, a famous botanist who lived at Ocean Point in the summer and is buried in Boothbay. There are small contributions from the collections of two of Maine’s best-known botanists, Kate Furbish and Merritt Fernald, too.

Melissa Cullina, right, a research botanist, helps volunteer Susan Wall, left, with a specimen she is transferring to archival paper.

Cullina pulled out some of the oldest plants in the collection, duplicate specimens donated by the Pringle Herbarium at the University of Vermont, including a pitcher plant that has lost some of its former glory but is still in excellent condition.

“These specimens were collected by Aaron Young Jr., who lived from 1819 to 1898,” Cullina said. “He was writing a flora of Maine, but he was doing it by making specimens of the flora of Maine. He started his botanical survey in 1847 on Katahdin. He was sort of requisitioned by the state to do it, so these were from the late 1840s and probably some from the 1850s.”

The volunteers come once a month to work as a group, but now that they have this dedicated space – the botany lab and the adjoining herbarium room – they work individually or in pairs as well. For the mounting, they use a special glue ordered from the Missouri Botanical Gardens. In a corner of the botany lab sit three old-fashioned plant presses filled with plants ready to be mounted. The volunteers have mounted so many plants they can’t, of course, remember them all, but Wall recalls those that were particularly challenging, like a plant from the genus Galium that had “just dozens and dozens of these tiny little leaves.”

“The things that have really been so special to me,” Cullina said, “are when I’ve seen the same plant as someone else in the same place, but 100 years later.”

Cullina does all the labeling, then the mounted plants sit with weights on them to ensure they’re well attached.

“It seems like such an archaic way of preserving something, doesn’t it?” Hoyt remarked.

Before being filed in one of the herbarium’s five cabinets, the plants go into a freezer for a week to prevent any pests from being introduced into the collection.

LICHENS AND MOSSES AND FUNGI, OH MY

The botanical gardens enters all of its label data online so researchers eventually will be able to sort the specimens by collector, county, date and so on, but it hasn’t yet started imaging the plants.

Many major herbaria have already digitized their collections, but for smaller collections it’s a slower process.

Hoyt Walbridge, another member of the team of volunteers working on the growing herbarium.

Langley said the College of the Atlantic is working on photographing plants, but she expects the project to take a few years. Acadia National Park co-manages the college’s herbarium because about a quarter of the collection is from the park and offshore islands. The data manager at the park is handling the herbarium’s digitization, Langely said, “but he has a lot of things on his plate.”

According to Cullina, the Consortium of Northeastern Herbaria received grants a few years ago from the National Science Foundation to help smaller regional herbaria digitize their collections.

Campbell said the University of Maine started its database 25 years ago. Information on all of its collections is now databased and available on national websites. The university started imaging in 2014, using two of the National Science Foundation grants to pay for photographing the vascular plants and fungi.

“Some larger places even have conveyor belts for imaging,” Campbell said. “A good graduate student can do 30 or 40 in an hour, so it’s slow going.”

All of the university’s higher plants have been imaged and are available to the public, Campbell said, but none of the mosses or lichens have yet been photographed. The fungi are somewhere in between.

Campbell wanted to fund a study of how climate change has affected plants in the alpine zone of Mount Katahdin, looking at flowering times, but the herbarium’s grants did not cover that expense.

That means there’s still lots of room for growth.

Meredith Goad can be contacted at 791-6332 or at:

mgoad@pressherald.com

Twitter: MeredithGoad