Identifying ancient irrigation: A new method using opaline phytoliths from emmer wheat

Abstract

A vital factor in the rise of the first state societies is the development of complex farming systems employing labour-intensive irrigation. Ancient irrigation is, however, difficult to recognize archaeologically. Here we report a new method for identifying ancient irrigation based on recognizing the increased deposition of silica in irrigated cereals. Our experiments showed that emmer wheat grown with irrigation in semi-arid plots produced phytoliths with greater numbers of silicified cells per phytolith than wheat that was dry-farmed. The presence of such large multi-celled phytoliths in semi-arid archaeological sites can be used as evidence for prehistoric irrigation. © 1994 Academic Press Limited.