Managed agroforests, swiddening, and the introduction of pigs in Pohnpei, Micronesia: Phytolith evidence from an anthropogenic landscape

Phytolith analysis is increasingly contributing to archaeological studies, especially in the context of agriculture in tropical regions. Plant remains from archaeological sites provide key information on such topics as site function, settlement, past dietary patterns, migrations, and landscape formation. However, in the humid tropics, where good preservation of organic materials is uncommon, identifiable plant macroremains are relatively rare. The inorganic nature of phytoliths makes them a useful tool in Pacific environments. In this study, we analyze phytolith remains from garden features in archaeological context from a western Pacific volcanic island, Pohnpei, Federated States of Micronesia. To understand the manipulation of floral environments, especially agricultural practices, we examine hypotheses regarding how agricultural landscapes were impacted by changes in social and economic systems during the island's late prehistoric and early historic periods; these changes include elaboration of chiefly feasting and the introduction of pigs in the 19th century. Previous research on Pohnpei (e.g. Haun, 1984; Ayres and Haun, 1985, 1990; Ayres et al., 2009; Athens and Stevenson, 2012) has examined Pohnpeian agriculture and sociopolitical change through the study of archaeological features and pollen cores. This project is one of the first, to our knowledge, to examine phytolith data from archaeological contexts on the island. Samples from archaeological gardening contexts document how agricultural landscape shows a response to swiddening, landscape succession patterns, and introduced animals within the managed agroforest. However, phytolith analysis alone is not sufficient and must be used in conjunction with other archaeological data in hypothesis testing.