Examining plants and their agency in nation-building.Adventive America places the forthcoming 250th anniversary of the United States into a broader international context by examining plants and their agency in nation-building. This nontraditional lens explores collectors, collections, and global botanical exchanges between the United States, Indigenous nations, Britain, Spain, Japan, and China, from the early American republic to the present day. Whether shipped in transatlantic Bartram’s boxes in the eighteenth century, showcased at the 1876 Centennial Exposition at Philadelphia’s Fairmount Park, emergent in the weedy ballast grounds along the Delaware River, or exchanged as part of the traditional seed-saving practices of