DISCUSSION Fire-reliant subsistence economies and anthropogenic coniferous ecosystems in the Pre-Columbian northern American Southwest Alan P. Sullivan III • Kathleen M. Forste Received: 29 June 2013 / Accepted: 14 January 2014 Ó Springer-Verlag Berlin Heidelberg 2014 Abstract Archaeologists working in the vast coniferous uplands of the American Southwest have commonly assumed that the subsistence economies of the prehistoric peoples who dwelt there focused on corn (Zea mays) agriculture, the erratic yields of which were supplemented with the unintensive collection of wild plants. In this paper, we develop an alternative to this orthodox view, in which we posit that human-controlled burning of understory biomass was a vegetation-community and successional- stage management strategy intended to propagate wild plants in bulk quantities. By comparing the relative fre- quencies and ubiquities of macrobotanical remains recov- ered from a variety of storage and consumption contexts with pollen frequencies from production and processing contexts, we show that the systematic encouragement of ruderals in pyrogenic resource patches (‘‘niches’’) was a sustainable practice that overcame natural limitations to biomass productivity and corn cultivation in pinyon-juni- per (Pinus edulis and Juniperus sp.) woodlands. Impor- tantly, these analyses indicate that low-intensity burning was a key aspect of fire-reliant subsistence economies that generated anthropogenic ecosystems whose composition and productivity were markedly different from today’s. Keywords Anthropogenic fire Á Ruderal agriculture Á Pinyon-juniper woodland fire ecology Á Prehistoric northern American Southwest Á Grand Canyon, Arizona ‘‘Through fire humans made earth habitable…’’ (Pyne 2012, p 47). Introduction Long considered a securely settled matter in the prehis- tory of the American Southwest (e.g., Gumerman and Gell-Mann 1994; Schoenwetter and Dittert 1968), the nature of ancient agricultural practices across broad areas of this culturally and environmentally diverse region is being systematically reconsidered as a consequence of new models (Rowley-Conwy and Layton 2011), new data (Powell 2002), and new understandings of the relations between people and plants (Smith 2001). The question as to whether the agricultural economies of prehistoric societies that once occupied upland forests of the northern American Southwest were based on water- dependent domesticated plants, such as Zea mays (corn), which is low-moisture intolerant, or fire-conducive wild plants (such as ruderals, which are low-moisture tolerant) has emerged as a pivot point of this rethinking (Sullivan 2014). The conventional, ethnographically inspired and justified view favours the water-dependent model, with its focus on understanding how moisture availability affects the success of maize agriculture and influences, as well, regional variation in population and settlement patterns (e.g., Spielmann et al. 2011). Our intention, however, is to share new archaeological and palaeoeco- logical data that support the fire-reliant model, which focuses on demonstrating the extent to which prehistoric burning and fuel-load ignition-management strategies ensured the sustained propagation of wild plants as the keystone component of prehistoric foodways (Roos et al. 2010). Communicated by F. Bittmann. A. P. Sullivan III (&) Á K. M. Forste Department of Anthropology, University of Cincinnati, 481 Braunstein Hall, Cincinnati, OH 45221-0380, USA e-mail: alan.sullivan@uc.edu 123 Veget Hist Archaeobot DOI 10.1007/s00334-014-0434-6