Colluvial slope agriculture in context: An extensive agricultural landscape along the slopes of Punalu‘u Valley, O‘ahu Island, Hawai‘i

Archaeological research on traditional Hawaiian agriculture has generally focused on two primary strategies: irrigated pondfield and intensive dryland cultivation. However, other cultivation strategies, such as colluvial slope agriculture, were practiced but have been less intensively studied and remain poorly understood. To begin to remedy this paucity of information, a joint education and research project between International Archaeological Research Institute, Inc., the University of Hawai'i at Manoa (UHM) Department of Anthropology, and Kamehameha Schools (KS) was conducted in Punalu'u Ahupua'a to examine an integrated slope agricultural, religious, and residential complex. Subsurface investigations and radiometric dating indicate that initial vegetation clearing of the area may have occurred as early as the late thirteenth to early fifteenth centuries AD. As early as the fifteenth century, some stands of economic trees were growing, which may have coincided with initial placement of boundary walls along some portions of the slopes. Major expansion of the surface agricultural infrastructure along the landscape occurred through the sixteenth and eighteenth centuries AD. Religious structures and associated features were built as early as the seventeenth century and later. These results situate colluvial slope agriculture within the broader context of traditional Hawaiian agronomic strategies and political and social processes across the Hawaiian archipelago.