Volunteers working to save Peaks Island trees from the invasive Asiatic bittersweet vines gather before a tree care session in October. Volunteers normally work on their own, but there were also two group sessions this year. Carl D. Walsh/Portland Press Herald

As a little girl in Connecticut in the 1950s, Thaea Lloyd, like all the neighborhood kids, was sent outside every November to collect the pretty red berries growing in nearby woods and fields and bring them home to decorate Thanksgiving tables. The bright, long-lasting berries dotted centerpieces piled high with pine cones and gourds, telegraphing the harvest season. A few weeks later, the berries adorned Christmas wreaths.

Few people then knew that these cheery, fire-red berries – the fruit of the Asiatic (or oriental) bittersweet vine – were highly invasive and a grave threat to native trees, shrubs and entire ecosystems. By gathering the berries, people were inadvertently contributing to bittersweet’s rapid takeover.

Today, Lloyd, a retired landscape architect, lives on Peaks Island, where she is founder, organizer and force of nature behind an unusual adopt-a-tree-in-perpetuity program aimed at saving island trees from this same deadly vine. She launched the program in May with 16 volunteers, mostly on trails near Battery Steele, the island’s abandoned World War II fortification. Seven months later, she has nearly 115 volunteers with almost 400 trees under their care.

She calls the effort “tree-age – urgent care for the trees.”

“It’s a drop in the bucket, but yet it’s substantial,” Lloyd said on a gorgeous, warm October morning as she oversaw or, more accurately, encouraged a group work session aimed at controlling the vines. (Because the berries turn red in the fall, the vines are easy to spot then.) “It’s meaningful.”

Peaks Island resident and retired landscape architect Thaea Lloyd conceived of and organizes Adopt A Tree on the island, which protects trees and shrubs from aggressive invasive plants. Carl D. Walsh/Portland Press Herald

Asiatic bittersweet is classified as “widespread” and “severely invasive” across Maine, according to the state list of invasive plants. It grows in all 16 counties (and in much of the Northeast, Midwest and Southeast). In parts of Peaks Island, heavy vines resembling thick mooring rope have twined themselves as much as 100 feet up trees, strangling them, smothering shrubs and saplings, and weakening nearby plants as a way to outcompete them, a strategy the state’s invasive plant biologist, Chad Hammer, likens to chemical warfare.

As Lloyd walked the trails and gestured toward the surrounding landscape and specific trees, she explained that several years ago, while taking a walk just like this one, she’d been “horrified and sickened that this (area) had been so neglected. And people are so accustomed to it, they just weren’t seeing the damage. But you can see (bittersweet) is to the top of those trees. All of these trees within a couple of years will be dead if we don’t take care of them.

“NOW,” she added, the word practically glowing in the air in red, capital letters. “Right now.”

The scars on the trees that were being strangled by Asiatic bittersweet are very much in evidence. If the invasive vine penetrates a tree’s cambium, the tree doesn’t have long for life. Carl D. Walsh/Portland Press Herald

PLANT BULLIES

The roots of the problem go back more than 125 years. Asiatic bittersweet (Latin name: celastrus orbiculatus) made its horticultural debut in the United States around 1886, according to a 2014 article in Arnoldia, the magazine of Harvard University’s Arnold Arboretum. It was brought here, like many other invasive plants, as an ornamental to beautify gardens in a newly prosperous America, admired for its brilliantly colored berries. The vine, as its name implies, is native to Japan, Korea and China.

It’s likely been in Maine about that same length of time, according to Maine State Horticulturalist Gary Fish, who said bittersweet was also commercially grown here to supply berries for Christmas wreaths. Generally speaking, it wasn’t until the 1970s that scientists began to understand the dangers of invasive plants, which in their native lands are restrained by the insects, mammals and diseases that evolved alongside them. In 2018, the state put Asiatic bittersweet on its first do-not-sell list of invasive plants. (Maine is also home to a native lookalike, American bittersweet, but it’s much less common. So, if you’re seeing the vine, it’s probably the invasive.)

There are several ways the vine could have reached Peaks Island. Birds that ate the berries, which contain the seeds, dropping them on the island as guano. The seeds floating to shore from the waters of Casco Bay. An islander planting the vine in a garden, where it thrived and spread. Island lore attributes its arrival to the U.S. military, said to have planted Asiatic bittersweet when it built the battery in the 1940s as a way to quickly camouflage it; the vine grows up to 12 feet a year. However and whenever it reached the island, the highly adaptable vine made itself right at home, employing a mix of aggressive tactics to ensure its success.

Although it prefers full sun and, in fact, climbs trees in order to reach the sunlight, the young plants can survive in full shade. It spreads by underground rhizomes, as well as the seeds. Whack it back in one place, it’ll simply sprout up a few feet away. “These plants are really smart,” Hammer said. “They know when they are under threat.”

It’s allelopathic, he said; the roots and rhizomes exude organic compounds that change the chemistry of the surrounding soil and sap the energy of nearby plants. Asiatic bittersweet strangles trees, wrapping itself around them or, in biological terms, “girdling.” Lloyd compared the climbing vines to boa constrictors. As the trees grow, the vines grow, too, cutting into the tree’s cambium, or cell layer. “Once the cambium layer is compromised,” Hammer said, “the tree will be dead in two years.”

And because bittersweet vines can be so large and heavy, girdled trees are more likely to topple in a storm.

“If it’s not being strangled, it’s being smothered,” Hammer went on. “The tree can’t photosynthesize, so it’s susceptible to other stresses like insects, disease and drought. If a tree is being attacked, and it’s not photosynthesizing, well, now its immune system is down.”

Eleanor Morse, a board member of the Peaks Island Land Trust, which owns the area by the battery that is the focus of Lloyd’s efforts, calls the vines plant bullies.

Adopt A Tree founder Thaea Lloyd labels each adopted tree with numbers on painted tin can lids so that volunteers can easily find their trees. Georgette Fehrenbach, one of more than 20 volunteers working on a Saturday in October, trimmed underbrush away from her trees. Carl D. Walsh/Portland Press Herald

FIGHTING THE GOOD FIGHT

Lloyd has loved trees since she was a girl. Walk in the woods by Battery Steele with her, and she seems to know the trees that grow there as intimately as the crew of volunteers. She can tell the species, of course, but also just how they looked – and how they suffered – before they were matched with a volunteer. Lloyd pointed to a massive and glorious maple tree. “This was a real coup,” she said. “You couldn’t even see this tree.”

She pointed to a scraggly, worn white pine sapling. “I passed that dozens of times. I never even saw it because it was covered. One day the light hit it just right and I could see one little tip of white pine.” She snapped a picture and posted it on Nextdoor Peaks Island, the online community forum where she finds most of her volunteers. “Can you find the white pine in this picture?” Lloyd asked. A young island couple spotted the photo, spotted the tree, adopted it and has excavated it from its smothering blanket of vines.

Lloyd got the idea for the program from Adopt-a-Highway. Why couldn’t the same idea work for trees, she asked herself. She borrowed the name, too, calling her effort simply Adopt A Tree. Other organizations in Maine fight invasive plant species, too, most notably land trusts. What makes Lloyd’s idea unusual is not only that volunteers adopt a specific tree, or trees, and promise to be responsible for it, but also that they make that promise for life.

“When you take on a tree, you pledge till death do you part,’ ” Lloyd explained, “that if something happens to you or you move away, a child or a friend will take over the job. People are pledging to do this year after year after year.”

That’s a concept Lorie Lanza understands. Her father, David Parker, grew up on Peaks Island and gave the island the Parker Preserve. She spent her summers on the island as a child, and still does; the rest of the year, she lives in Connecticut. Lanza and her husband adopted a grove over the summer. (“Once you take down the vine, you end up inadvertently clearing more, because it’s everywhere. I guess we adopted some siblings,” she said, laughing.) When her 20-something daughter visited over the summer with a group of girlfriends, Lanza took them to see the grove.

“I explained to her that’s going to be part of her inheritance,” Lanza said. “If she’s going to inherit the house on Peaks Island, she’s going to inherit the bittersweet.”

“Sounds like a good tradeoff,” her daughter told her.

Volunteers pick their own trees, mostly near the ABC trails, each named for a letter of the alphabet, an area Lloyd said she is focused on for now “because the trees are so imperiled.” They agree to visit several times a summer on their own schedule to sever the Asiatic bittersweet. The idea is to keep their commitment manageable and fun. Lloyd tags the trees with numbers she has painted on tin can tops. She keeps a chart that lists each tree and each adopter, though the chart also seems to live in her head.

“Usually they’ll see a tree they’re drawn to,” Lloyd said. “It’s like going to the Humane Society (to pick a pet). I’ll say, ‘We’re going to walk the trail so you can see everything. If a tree speaks to you …’ ” she tells them, “and they look at me like, ‘A tree isn’t going to speak to me!’

“But it does.”

The volunteers describe her as passionate, knowledgeable and ebullient.

“Thaea has such an unbelievable spirit about her,” said volunteer Ellen Hurley Green, who adopted a single beech tree last spring but already cares for a copse (in part, she added, to do penance for all the bittersweet berries she used to unknowingly use in floral designs). “Her enthusiasm is so contagious.”

Lloyd, who moved to Peaks Island seven years ago after a 45-year landscaping career in the Atlanta area, instructs new volunteers on the tools they’ll need, on the importance of removing pruned vines from the woods so they won’t regenerate (they are collected and disposed of), and on how to make the cuts: Try to pull out as much of the root as you can (but don’t hurt your back!). If the root won’t come, cut the vine.

Hammer advises the “window cut,” which involves removing a section of vine that extends from the ground up to the height of a person’s chest to “eliminate a trellis for a sprout to climb back up into the tree.” If the Asiatic bittersweet vine isn’t cut at least three or four times during the growing season, he cautioned, it will re-sprout with even more vigor.

Lloyd knows the Adopt A Tree program won’t eradicate Asiatic bittersweet. That horse is out of the barn. Her goal is to keep it in check. She has energy to rival that of the vine, but no budget. Adopt a Tree, Lloyd said, “is just a passion, an absolute priority for me. You just have to save a life. I just couldn’t go to my grave … ” the sentence hung in the air. “This is what I could do to help.”

ONWARD AND UPWARD 

Next year, Year 2 of the Adopt A Tree program, Lloyd hopes to double the number of volunteers. She says that goal may be “pie-in-the-sky” but adds that she is “stubborn and determined.”

Many of the volunteers are retired. They have more time, Lloyd said. But the program has also attracted young couples, summer people, a husband and wife who have taken on a tree for each one of their daughters, a divorced dad who brings his teenage daughter as a way to spend time with her, a grandfather who comes with his 6-year-old granddaughter and plans to one day leave the trees to her care.

“The idea that she had is such a good one,” Morse said. “People, and children, too, who learn to love one tree, by extension begin to learn to love many trees.”

Some of the volunteers hope Lloyd will consider exporting the adopt-a-tree concept. Hurley Green, who has summered on Peaks Island since childhood, said she recently emailed Lloyd to ask if she’d consider patenting and franchising the program. Asiatic bittersweet has taken over a park near Hurley Green’s home in Albany, New York. Everybody knows of a natural place that needs care and love, Hurley Green said. “The more we can do for our planet in our own little neighborhoods, the better our lives will be, and our children’s and grandchildren’s lives.”