Since uncharred seeds recovered from archaeological deposits may be modern intrusions, researchers must evaluate each uncharred seed assemblage before assigning archaeological significance to it. When depositional circumstances are established, seed remains can yield primary data about diet, farming practices, and the spread of imported cultigens. Three uncharred seed assemblages are evaluated—one from Morven (Princeton, New Jersey) and two from the Calvert site (Annapolis, Maryland). The Morven seeds are modern. Seeds from a dry crawl space at the Calvert site probably date to the late 18th century, but rodent disturbance could have introduced more recent materials. Waterlogged seeds from a sealed 18th century well most securely reflect 18th century debris.