Just guessing here, but you've probably never heard of a wildflower called Canby's mountain lover or one known as Carolina elephant's foot, both very rare in this part of the world.
But a growing number of plant people like Steven Wright are making it their business to study, preserve, and educate the public about these imperiled species before they vanish forever from the landscape.
"Anything that's unusual or odd is cool to me," says Wright, horticulture director and curator of plant collections at the Jenkins Arboretum in Devon.
In 2012, he created a small nursery deep inside the arboretum that now boasts dozens of rare and endangered plants - mountain lover and elephant's foot, and other colorfully named species, such as Southern blue monkshood, Meehan's mint, Clinton's wood fern, Virginia fanpetals, and more.
Though hyperlocal, the project taps into the long-standing, and increasingly urgent, problem of global plant extinction caused by habitat destruction, war, disease and pollution, changing climate and extreme weather, competition from invasives, overcollection of plants in the wild, and overgrazing by animals.
According to Botanical Gardens Conservation International, about 20 percent of the world's 400,000 plant species are threatened with extinction. In Pennsylvania and New Jersey, the percentage is somewhat lower - about 15 percent - but if other threats are included, such as being rare or vulnerable, the percentages would increase.
And though Jenkins, a 46-acre island of serenity in a mad, mad world, may seem an odd place to take on the ecological adversity and human perversity that is swallowing up native plants everywhere, where else might one expect to find heightened consciousness than in a public garden so rooted in nature and the earth?
Jenkins executive director Harold Sweetman sees the new nursery as "a very small thing in a very big story," but a long-term commitment to biodiversity nonetheless.
Small, yes: The nursery comprises dozens of plants in about 1,000 square feet of low raised beds just outside the home provided for Wright and his wife, Mary, on arboretum property.
The site is far from Jenkins' public areas, surrounded by woods, and fenced to keep deer out.
And, yes, this could take a while: The process - of collecting seeds, cuttings, or plants; creating the right mix of soil, light, and water; then nurturing seedlings to the point where they can be successfully propagated - can take years, and in the end, can fail anyway. (American ginseng and Fraser's sedge have already bombed.)
Wright happily reports that 2015 was the first year his collection produced significant numbers of seeds.
On one of November's last golden days, with Mary rapidly approaching her due date with the couple's first child, Wright eagerly showed a visitor around the nursery - the plant nursery, that is, which is all brown sticks and funky seed heads right now.
But he was enthusiastic about some of his favorites: native bleeding heart, whose odd little flowers bloom all summer; Barbara's buttons, with their charming puffball blooms; and the elegant prairie or gray-headed coneflower.
Someday, he hopes to propagate enough to plant around the arboretum, and possibly offer to the public at plant sales, design guided tours and lectures.
"You can go just about anywhere to see native plants," he says of the arboretum's specialty, "but things that are rare and endangered you hardly see anywhere. I'm such a plant nerd I wanted to do something interesting to set Jenkins apart."
By now you may be wondering why anyone beyond a bunch of plant nerds - and scientists - should care about these obscure plants.
"Without plants, we all die. I don't think people realize that," says Casey Sclar, executive director of the American Public Gardens Association in Kennett Square, which has 585 members in the U.S., Canada, and abroad.
Plants provide food, habitat, oxygen, and medicine. They also sequester, or store, carbon dioxide, which mitigates global warming. Everything, it seems, is connected to everything else, and plants are right in the thick of it.
Robert J. Cartica of the N.J. Department of Environmental Protection Office of Natural Lands Management, which focuses on preserving plants in their native habitats rather than in nurseries, has been working to preserve one such plant: American chaffseed.
New Jersey used to have 20 "populations" of this perennial herb; now it has one, on state land in Burlington County. "It's our responsibility to make sure this species doesn't wink out," Cartica says, meaning become extinct.
John Muir, the noted American conservationist, provided what may be the simplest explanation of why that is so: "When we try to pick out anything by itself, we find it hitched to everything else in the universe."
It's no accident, then, that public gardens, including many in the garden-rich Philadelphia area, have made the conservation of rare and endangered plant species an important component of their mission.
"Many people view public gardens as just pretty places to go visit, and they are that," Sclar says, "but . . . many gardens are establishing conservation of these plants as a priority now."
A final word about priorities.
Wright has more than endangered plants on his mind these days. On Dec. 3, he and Mary welcomed an 8-pound, 3-ounce boy to their personal ecosystem. May he thrive in the nursery.