MR. KOJO NNAMDIIt's always been an important piece of architecture. The greenhouse of the Wye family plantation on Maryland's Eastern Shore is believed to be the only surviving 18th century greenhouse in North America. But the building isn't just a piece of important American history. For years, it also hid the West African heritage of the slaves who built it, slaves who left clues to their cultural and religious beliefs in the very structure of the building. Archeologists working at the site have discovered some of those clues, subtle signs like a coin, arrowheads and smooth stones hidden in the building's brick work.

MR. KOJO NNAMDIMark Leone from the University of Maryland has been leading that work and he joins us for the second in a two -- in a three-week series looking at some of the archeological projects taking place in our region. Mark Leone is a professor in the Department of Anthropology at the University of Maryland. He is the creator of the Archeology in Annapolis program. Thank you so much for joining us.

PROF. MARK LEONEMy pleasure.

NNAMDIThis building, known as the orangery, is considered one of the most beautiful and important buildings in Maryland. Before we talk about the archeology, tell us a little bit about this building and why it's significant.

LEONEThank you. The greenhouse at Wye House was built first in the early 1770s by Edward Lloyd IV, and then it was redesigned probably by him to take its current shape after the revolution, probably around 1785. It's the only surviving greenhouse that anybody knows about in North America. It's a very beautiful building. It's 85 feet long. The south facing room, which is the greenhouse proper, is about 20 feet wide, but it's two feet high, two-stories high. And on top of that is a billiard room, all from the late 18th century. And behind that are two rooms, one a furnace room and the other a slave quarter.

LEONEBut because the building is so beautiful, because the building is a direct copy of Palladio's Villa Emo outside Venice, it's regarded as one of the most beautiful buildings and most famous buildings in Maryland. And you can see pictures of it at the Library of Congress, historic American building survey website. Photographs are really good.

NNAMDIBut one of the things you found in your archeology is that this building has what I guess you might call a hidden West African face.

LEONEAny greenhouse in Europe, like the famous greenhouses at Versailles and those that are associated with English country houses, are gonna be different from ours. And I think it's important to call this ours. Ours is an African-American building as well as something derived from Palladio and filled with beautiful flowers. Africans, of course, probably built the building, but African-Americans ran the building, which means they ran the heating system and they ran the watering system, cultivated the plants. And what we didn't know is what they introduced from the wild and how they domesticated plants and created a whole cuisine out of this building.

NNAMDIThe orangery is on the Wye plantation outside Easton. It's been in the same family for hundreds of years since, apparently 1650. The 11th generation of descendants of a man name Edward Lloyd now live there. Tell us a little about this family and why they decided to open their estate to researchers.

LEONEThe University of Maryland College Park, where I've taught for over 30 years, is a Land Grant institution, and the Tilghman family, who are Lloyd descendants, wanted a research relationship to our university. And we made an agreement with each other that we would excavate the areas where slaves lived. And in the long run, that included the great greenhouse that is so famous. But the Tilghmans take very good care of this property, which is almost completely intact. I mean, it's very rare that you have a plantation that's been in the same family that's intact for 350 years. But that's -- that makes it a Maryland gem.

LEONEBut while there are descendant communities of African-Americans nearby, all of African-American heritage there had been removed after emancipation and certainly by 1900.

NNAMDIWe're talking with Mark Leone. He is a professor in the Department of Anthropology at the University of Maryland and the director of the Archeology in Annapolis Program. I think I may have interrupted you.

LEONESo the university does the archeology, but the request for the archeology and the exploration of African-American heritage comes not just from the Tilghman family but from the people of Unionville, whose ancestors were freed by the Union Army from Wye and they returned after the war to found a series of communities. The liveliest one now is Unionville. And one of the first things I did after the invitation to dig at Wye was to take my graduate students to Saint Stephens AME in Unionville and ask what they would like to know.

LEONEAnd one of the things they wanted to know is about slave spirituality, which led to our trying to understand how African traditions had been used, kept alive, celebrated at Wye. And in the greenhouse, we found a series of bundles, as they're called, under the doorstep of the quarter and in the furnace that made the heating system in the greenhouse work.

NNAMDIIf you'd like to join the conversation, you can call us at 800-433-8850. Do you have questions about local archeology or about the history of slavery on the Eastern Shore? If so, call us at 800-433-8850 or you can go to our website kojoshow.org, join the conversation there. Send us a tweet, @kojoshow, or email to kojo@wamu.org. This estate is also important because of its role in the life of a very famous American, Frederick Douglass.

LEONEDouglass has become more and more important in our lives. He wrote three, possibly four autobiographies, and in each one, the opening chapters described his life as a boy at Wye House, which was around the 1820s. And the purpose of his autobiographies is to indict and help eliminate slavery, and he was very effective with that. But later on, he also understands that elimination of slavery is very much like promoting -- it's analogous to promoting women's suffrage.

LEONESo he's an astonishing American writer, great clarity and a man who thought extremely broadly about social relations and social stratification, and he didn't approve of any of it. His description of Wye House is our greatest guide to what happened there in the early 19th century. On the other hand, the point of archeology is to complement him to discover things that he didn't say. And while he describes the garden, he never mentions the greenhouse. And while he describes heroes and he describes daily life, he doesn't really describe culture, and he certainly doesn't describe African religious traditions that were practiced there, although he shows some respect for them.

LEONEAnd he certainly doesn't show anything about African-American gardening, African-American use of local plants, African-American medicine, and the African-American traditions, which is still alive and well there. So this is in no way a criticism, he has a particular point. But Douglass also allows us to understand a part of Chesapeake African-American culture that he doesn't talk about.

NNAMDIYou've been doing archeological work at the estate for six years. Did you know that there were things of archaeological significance in the orangery?

LEONENo, we didn't. What I knew was that this is an important building. We didn't even know that the archaeology was intact, and the archaeology's intact down 3 1/2, 4 feet. So the whole building is there. What we knew is that there was no other that survived completely. So one of the things we did was to excavate and recover what's called fossil pollen. And we had Heather Trigg up at UMass Boston analyze the pollen remains from the 18th and 19th century so we could find what was actually grown in the greenhouse.

LEONEAnd while it's called an orangery in the 19th century, one of the things we found is that there were no oranges and lemons there in the 18th century. What they were, were pond lilies and water lilies. Nobody knew that before. But above all, what's really interesting, it took an awful long while to figure out. There's the pollen from medicinal plants, practical plants like rushes used for scouring pots, and then all kinds of plants that are used for food in the African-American tradition, like broccoli and greens and eggplants and tomatoes.

LEONESo what we suddenly have here is one of the spots where we can see how old African-American gardening traditions really are. And the greenhouse is therefore not just a place for oranges. It's a place for experimentation. It isn't just a European building transplanted in one way or another from Venice. It's a place where one can see the creation of an entire culture where spirits from the African traditions and foods are put together to create a whole way of seeing gardening, which is both food production and eating.

NNAMDIBecause even though we're talking about a greenhouse, you found stones hidden in the bricks of the foundation, as well as charms at the entrance to the slave quarters of the orangery that indicated that there were people living in that building. Tell us about some of the artifacts you found.

LEONEOn the north side of the greenhouse is a building that has a loft and a hearth and a fireplace. And when we, as a kind of -- when we were introduced to the building in a colloquial fashion, this was a potting shed. It was a storage room when we actually looked at it. But what we proved is that people lived there from 1785 to 1820. We know those dates because we can date the broken dishes really quite precisely. But nobody lived there after that. So these are the people. And the material is not expensive. So we figured that it has to have been a slave quarter.

LEONEIn the doorstep, we found a bundle -- two projectile points which are prehistoric, and a coin. And this is a signature that we've come to understand archaeologically to protect the environment and to utilize spirits that come and go, spirits of the dead. And, of course, there's a big cemetery right outside as well. And there's a stone in the vault of the furnace. So when this material gets repeated time and again, we understand it awfully well from Annapolis and the American South. You can see that African traditions are being utilized and spirits are being called on, protected, used by the Africans and African-Americans who actually ran this whole environment.

NNAMDIWhat have you learned about the beginnings of African-American culture through this archaeological work, especially in this area?

LEONEThe area that I actually started in is in Annapolis. And starting around 1990 when my wife and I returned from teaching in Cape Town, I worked with African-Americans, intellectuals, people who had a deep interest in whether or not they could find the origins of African-American culture in Annapolis to get some questions. And one of them was what's left from Africa. And when that question comes to why our discovery through the pollen, through the religious artifacts, is that there's a whole tradition that we can see alive, intact, that goes as early as the 1780s. Probably it goes earlier.

LEONEBut one of the things archaeology does is that it gives a lot of details. But it also sees that this is a single system of plants and spirits. And it leads to the kind of work that many people have done in the American South -- African gardening traditions, African-American gardening traditions that include swept yards and plants and foods, recipes and so forth, but all in the world also of managing, using spirits for protection, harming -- not harming -- keeping harm away and for curing.

NNAMDIHere is Dantes in Huntington, Md. You're on the air. Go ahead, please, Dantes.

DANTESHi. I come from a local area in Huntingtown and Calvert County. And around the area, there's a lot of slave houses that have become dilapidated and (word?). I was curious to ask if you think there's anything of value in a lot of these homes that are falling to ruin.

LEONEThey're very valuable. In 20 or 30 years, most of those will be gone. And it's really essential that they be kept intact and protected, and that the ground around them be kept intact and not dug up. This is the beginning, in the last 30 years, of an exploration and a celebration of African-American heritage and culture, and those buildings are where we can find out what we don't yet know -- the depth, the history, the integrity, the details, the spread. Just how big is this? How did African-American Christianity cope with, get amalgamated to, African traditions? There are answers, archaeologically, in all those buildings. Those are the treasure of the Chesapeake. It's one of many sets of buildings that we have to work to keep together.

NNAMDISo please talk a little bit about the Archaeology in Annapolis program. The program's been going for a number of years. Give us the CliffsNotes review of the archaeologically significant sites in the state capital.

LEONESure. Thank you very much. For many years, the university and Historic Annapolis Foundation and now the mayor and the city council, and we work together. So we looked at the city's gardens. We looked at the city's plans. But our greatest contribution is really twofold. We've begun to understand that there is an African-American heritage in the great buildings of the city, in the William Peck House, in the Charles Carroll House, in Reynolds Tavern. And because there was a large community of free African-Americans helping each other become free well before emancipation, we looked at the Maynard-Burgess House.

LEONEWe now look at the James Holliday House. And we've added, through archaeology and understanding, that Annapolis is an African city, an African-American city, as well as a city that shows the origins and fight for American independence. So it is a city about freedom for many people. The second thing we did, which is part of the commitment that my graduate students and I make, is all of this material is shared as quickly as we can with everybody. So in the early 1980s, when archaeologists had fences -- still had fences up around their sites -- we took them all down.

LEONEAnd I was really blessed by knowing a theater producer that took my Maryland undergraduate wallflowers at the time, and they're not wallflowers anymore, I can promise you, and taught him how to explain archaeological method in 10 minutes in the July heat, and it worked really well.

NNAMDIMark Leone is a professor in the Department of Anthropology at the University of Maryland and the director of the Archaeology in Annapolis program. Thank you very much for joining us. It's my understanding you've got at least another year of work that you'll be doing at the Wye estate. Good luck with that work.

LEONEThanks so much, and thanks for inviting me and the voices of my many graduate students here.

NNAMDIAnd thank you all for listening. I'm Kojo Nnamdi.