Zapoleon was in her mid-90s when she died two years ago, Minney said.
Eidolon was named for the phantom women Zeus created from mist and light in Greek mythology, he said. It means "image of the ideal," Minney said.
Zapoleon and her late husband, Louis Zapoleon, bought the property in 1945, and they were concerned about its protection in the future and began working with the Conservancy in the early 1970s, he said.
"She was forward thinking," Minney said.
He said Marguerite Zapoleon was an economist from Washington, D.C., and is the author of "Everyone Needs a Mountain: Or Skylife at Eidolon," which was published in 1985.
"Our goal as was Zapoleon's concern is to assist the community to learn about nature," Minney said.
The Potomac Valley Audubon Society (PVAS), which also co-manages Yankauer Preserve in Berkeley County, plans to conduct education activities at Eidolon to teach students about nature.
Minney said the Nature Conservancy has a well-established relationship with PVAS, and it will help take care of Eidolon.
Peter Smith, PVAS president, said "we look forward to working with the Morgan County community to get this preserve up and running and making it a valuable resource for the community."
Minney said a sign marking the entrance off Orleans Road will go up in the spring. An open house ceremony also is planned for the spring.
Smith said the preserve is used for hunting, so visitors should use caution especially during deer hunting season in November and December.