SYLVAN KAUFMAN, conservation curator at Adkins Arboretum, is an easygoing plant ecologist who in 2002 brought a PhD from Rutgers and three years of post-doctorate experience at Harvard to this 400-acre botanic garden on Maryland's Eastern Shore because, she says, "it had the right mix."

That mix, for Kaufman, was personal -- the arboretum wasn't academia and she liked the idea of living at some modest remove from a city -- but it was also very much professional. "It was a unique position at an up-and-coming place," she continues. "There was the chance to do some of everything: conservation, botany, plant ecology, land management. The greatest advantage of a site like this is that it's based in scientific theory, but it also allows us to show science in its applied form."

Kaufman's job at Adkins, which is nestled off Route 404, 30 minutes east of the Bay Bridge, includes many such applications. When she's not running public education programs or training volunteers, for instance, Kaufman expends a great deal of time and energy keeping the preserve and its 600 species of indigenous Delmarva Peninsula flora as free as possible of invasive plants. The subject is one of her specialties -- she is co-writing a field guide to North American invasive plants -- and her efforts don't just keep the arboretum unspoiled. They also generate important data for scientists, homeowners, developers and anyone else tussling with the detrimental (and hopefully accidental) introduction of non-native plants into the mid-Atlantic coastal plain.

"It's amazing what a few birds can bring in," Kaufman says, and the short list of her adversaries on the Adkins site -- and, often, in local yards -- includes oriental bittersweet, Japanese honeysuckle, tree-of-heaven (the " 'Tree Grows in Brooklyn' tree," she points out) and a recent but obnoxious interloper, the aptly named mile-a-minute vine, a perennial that can quickly choke the life out of meadows, thickets and forest edges.

The hiring of Kaufman neatly represents the arboretum's push to make on-site research and collaboration with the national academic community a priority, but science is hardly the entire Adkins story. Indeed, to the beachgoer stopping on the way to or from the Delaware shore, the most obvious attraction of the arboretum might be four miles of trails looping past its meadows and through its bottomland forests, all of them open year-round to walking, biking and, weather allowing, cross-country skiing. Canoeists and hikers from bordering Tuckahoe State Park to the north can meander through the site as well, and birders and gardeners from all over the Delmarva Peninsula have been regulars since the arboretum opened as a state-run operation 25 years ago. Two annual native plant sales, one each in spring and September, are enormously popular, a chance to shop for hundreds of local ferns, grasses, flowering perennials, shrubs, trees and vines, purchases that raise significant operating funds and come complete with the staff's expert suggestions for selection, care and arrangement.

Ellie Altman has run Adkins Arboretum since 1998, when, as a freelance landscape architect and member of the organization's board of trustees, she chaired the search committee that eventually (and only after her voluntary recusal from the selection process) chose her as executive director. Her first year on the job coincided with a major shift in Adkins's status, when the state of Maryland granted the arboretum nonprofit independence and a 50-year lease on its land. In the seven years since that change, the organization has gone from one part-time and three full-time employees to seven of each, from a handful of volunteers to more than 100 and from 35 to 1,300 members.

"The operation is not unlike a university in its charge for education, research, outreach," Altman says, and she might have added that it is also not unlike a community center and oversize neighborhood park in one. The arboretum hosts revolving environmental art exhibitions, indoors and out (think Christo on a very tight budget), as well as walks and tours of the site, guided by one of the site's 30-plus docents. Each Halloween the trails are booby-trapped with ghosts and ghouls for an annual costume contest and hayride advertised as "not for the faint of heart." A family festival each November and December, meanwhile, includes a greens sale, a "Grand Illumination" -- an outdoor display of lights and decorations -- and a caroling walk.

Amid all this activity comes the most ambitious step of all: a $5 million capital campaign, close to two-thirds complete thanks to several years of concerted grant-writing and private fundraising. In April, the arboretum will host a gala kickoff for the public portion of the campaign, aimed at reaching its goal by way of matching-grant funds from individual donors.

"In early 1998, when we were made independent and granted the lease to run the arboretum, the one mandate we received from the state was to develop a master plan for the organization," Altman explains. That master plan occupied much of her first year on the job, and the chronology developed eight years ago is finally coming to fruition in an arresting design for a greatly expanded visitors center created by the acclaimed architecture firm Lake/Flato of Texas. The 9,500-square-foot addition, complete with a 150-seat auditorium, is set to break ground in fall 2006 and will be built with an eco-friendly parking lot and other site renovations, including an expanded system of boardwalks, by landscape architects Michael Van Valkenburgh Associates.

For Altman, planning the arboretum's expansive future has been satisfying from several angles. "Because of my background," she says, "it has been a life's dream to work so closely with some of the country's best designers." Altman explains that about half the $5 million goal is earmarked for the building and site improvements, which will give the arboretum much greater visibility and the room to "properly" host such events as its annual Spring Garden Symposium, which collects horticulturalists, landscape designers, authors and others from across the country for a day of lectures and demonstrations.

The other half of the funds will go to administrative costs and an endowment aimed at ensuring the long-term success of the arboretum. "We've got the room to do much more. We can bring in 50,000 people each year instead of 15,000 and still give them a pleasant experience," Altman says. "People think we're about saving nature, and of course we are, but I like to think of it as creating better human habitat, developing a balance between humans and nature. It's thinking about how people are stewards of their own nature, helping them to see ways to incorporate nature into their own landscapes."

ADKINS ARBORETUM -- 12610 Eveland Rd., near Ridgely, Md. 410-634-2847 or Grounds and visitors center open daily 10 to 4 except major holidays. $3 adults, $1 children, free for arboretum members. Fall native plant sale is Sept. 10 from 9 to 1. Take U.S. 50 east from the Beltway to U.S. 404. Turn left onto U.S. 404 and go about seven miles to the second stoplight at Md. 480. Turn left onto Md. 480 and then take the immediate first left onto Eveland Road. The Arboretum is two miles ahead on the left.

Adkins Arboretum holds two native plant sales a year for residents to shop for local ferns, trees and more. Plant Sale volunteers Barbara O'Toole, left, and Sandra Lyons at the Adkins Arboretum's annual Fall Native Plant Sale in Ridgely, Md. The Adkins Arboretum, which includes a wetland area, features 600 species of indigenous Delmarva Peninsula flora.