Orange County, North Carolina was home to more than 5,000 enslaved people at the time of the Civil War. Each of them had family. Each family buried its dead. By conservative estimate, the county contains the remains of tens of thousands of enslaved people in burial grounds that have never been formally documented — unmarked, unmapped, and in many cases actively threatened by development. The Periwinkle Project is an effort to find them.
The project uses a combination of LiDAR-derived terrain analysis, geodesic viewshed modeling, and historical deed research to narrow the search. The core insight driving the methodology comes from the archaeology of plantation landscapes: enslaved burial grounds were not hidden. They were placed where the enslaver could see them — within walking distance of the plantation house, on ground visible from it, at a distance consistent with patterns documented at known cemetery sites across the region. Surveillance was the point. The planter wanted to know what was happening at the burial ground.
This means we can model the search zone. Using the locations of documented plantation houses as observer points, we compute a geodesic viewshed — the ground visible from each house within an 840-meter radius. We then cross-reference that visibility zone with geomorphon analysis of high-resolution LiDAR data, looking for the subtle terrain signatures — shallow depressions, slight mounding, anomalous micro-relief — that characterize burial features under forest canopy. The result is a set of candidate locations that can be investigated in the field.
The method has already produced results. Analysis of the Holden plantation property identified a candidate location that field investigation confirmed as an intact enslaved cemetery. Although the Holden enslaved cemetery was not marked by periwinkle (Vinca minor) ground cover, many of the other enslaved cemeteries visited in this effort are. Periwinkle is a traditional ornamental groundcover planted in cemeteries. Periwinkle spreads very, very slowly in North America, where it is an exotic species. Consequently, anywhere we find periwinkle, we know that someone planted it there.
The Periwinkle Project is the work of Mark Chilton, former Register of Deeds of Orange County and doctoral student in Geography at the University of North Carolina at Chapel Hill, where his research focuses on the spatial organization of enslavement in the North Carolina Piedmont. If you have information about a possible enslaved burial ground in the NC Piedmont, or if you are a descendant family with knowledge of a cemetery on land that was once part of a plantation, please be in touch.