WHATLEY — John Berryhill and Jesse Bellemare wade through a sea of herbaceous plants, leaves and goldenrod flowers brushing against their waist, until their keen eyes spot three 6-inch tree seedlings, barely visible through the thicket of grasses and brambles.

Berryhill, director of the Botanic Garden of Smith College, and Bellemare, associate professor of biological sciences at Smith College, are excited to see the tiny trees they transported from the greenhouses at their Northampton campus to The Ada and Archibald MacLeish Field Station in Whately have survived the Massachusetts winter.

The men begin clearing away the grasses and native weeds encroaching on the delicate mountain magnolia, a species native to the southern Appalachian mountains, to find the seedlings have grown slightly, the species’ characteristic double lobes at the base of the leaves still intact.

The three plants are the first steps toward building a collection of mountain magnolia, known in the scientific world as Magnolia fraseri, in western Massachusetts, a climate similar to the trees’ home habitat in higher elevations of the Appalachian Mountains in the states of Virginia, West Virginia and Kentucky.

This species and the seven other species of magnolia native to North America are not a current conservation concern, but there are warning signs that not all is well. In those Appalachian states, the scientists’ data show that magnolia fraseri’s trees higher up in the mountains, which is much cooler than the base of the mountain, are fairing much better than the trees toward the bottom of the mountain. Climate change could shrink its habitat.

The data indicate that [magnolia fraseri] is highly climate sensitive, but the trees weren’t moving up slope to cooler conditions as scientists might expect them to do.

“It was sort of the information we’d expect to see that would offer an indicator of the early phases of a large-scale population collapse and fragmentation,” Berryhill said. “If that were to occur, you might lose some of the genetic diversity that will serve any species well, particularly in a climate changing climate.”

Berryhill and Bellemare aim to conserve mountain magnolia before climate change pushes the species into a more vulnerable position, but they need to act now, prior to the species’ decline. Yet magnolia cannot survive the drying and freezing preservation methods typically used to document and conserve a plant, so the two must cultivate a living collection of mountain magnolia in their own backyard.

That’s where their work in Whately comes in. The conservation project, which will eventually become a large botanical garden of mountain magnolia, is part of the Global Conservation Consertia, a project conserving plant species which cannot survive traditional conservation methods for plants. The Consertia organizes and maintains these networks of conservation sites for magnolia, oak, maple and eight other plant families.

Normally, researchers document a plant species by drying and freezing seeds of a species from different areas of the plant’s viable habitat and then store it in a facility where they can conduct further research, reintroduce the species or save any genetic diversity lost as the species population declines. This method is called seed banking.

But magnolia seeds cannot survive this process. The best way to conserve the species and its current genetic diversity is to maintain a collection of living plants, or several collections in case an extreme weather event wiped out a collection.

“This collaborative approach to stewarding hundreds of trees which presumably capture the genetic diversity of the species, and also encode enough for redundancy that if something happened at one of these sites, you’d have a backup at another site or two,” Berryhill said.

Berryhill and Bellemare are in charge of collecting seeds from various populations of mountain magnolia, cataloging the origin of these seeds, growing most of the trees locally, and then shipping duplicate trees and seed to other botanic gardens. Smith College also hosts one of these duplicate collections for oak trees.

“This effort across these different consortia is to sort of create these well documented collections where the source populations are known and individuals are tracked,” Bellemare said. “It’s sort of adopting the model that used with endangered species where they’re tracking parentage and pedigrees in a way that wasn’t always done in botanic gardens.”

Bellemare and Berryhill decided to put the mountain magnolia garden in Whately because the climate of western Massachusetts bares many similarities to the environment of high elevations in the Appalachian Mountains. That the trees surviving their first New England winter supported their hunch, but so far the biggest challenge for Berryhill’s team at the Smith Botanic Gardens is cultivating the young trees in the greenhouse.

“We have some 1 year olds that are only about 6 inches and we have some 2 year olds that are up to a foot or more. And it’s a tricky plant to grow as a small tree,” Berryhill said.

Conservation is the future of botanic gardens

The project represents a major shift in the philosophy around species collection for botanical gardens. In the past, researchers collected a variety of plant species from different areas all over the world, competing with other curators and scientists to establish the most unique collection.

“Those single individuals, those small handful of specimens don’t provide a whole lot of benefit for the overall sort of conservation status of the species in that they don’t represent that much genetic diversity,” Bellemare said.

The new model houses many trees of a single species. Instead of having two mountain magnolia, two umbrella magnolia and two southern magnolia, the botanic garden being established in Whately is all mountain magnolia, but two individuals come from seeds found in northern Virginia, two originate from Georgia and two are from Kentucky.

“If you’re looking to conserve wolf populations, you wouldn’t want to be keeping a poodle and a dachshund and a beagle,” Berryhill said. “Things that really have adaptations that have been selected for by human breeders to serve our interests and our desires as opposed to the traits that you’d want in a diverse genetic wolf collection.”

Smith’s mountain magnolia botanic garden currently consists of three seedlings, and most of the trees and seeds the researchers have now come from Virginia and Georgia, so there isn’t a lot of genetic diversity in their collection. To remedy this, Berryhill and Bellemare will travel to western Kentucky and western Virginia with two interns from Smith in mid-August, collecting seeds for other populations of mountain magnolia.

“We’re really excited to be able to meet today’s Smithies with this story, because it really is compelling. If I just bring them through the garden and just talk about you know, this is perovskia, this is chrysanthemum, it’s beautiful, but that doesn’t spark curiosity. And this story sparks curiosity and in a way that simply walking through a garden doesn’t always do,” Berryhill said.

Emilee Klein can be reached at eklein@gazettenet.com.