Prescribed Fire as the Catalyst to Control Prickly Pear Cactus Encroachment and Restore the Ecological Integrity of Texas Rangelands

Abstract

There is a pressing need to assist resource managers and ranchers with the recovery of degraded rangelands in the Edwards Plateau region of Texas. In the last century, the plant community in this rangeland savanna ecosystem has experienced a significant shift in vegetation structure and composition, as well as a considerable decline in ecological function and productivity. The widely observed increase in Opuntia spp. (prickly pear cactus) encroachment is of economic and ecological concern for rangeland producers and managers. Prickly pear is a hardy succulent with an aggressive competitive nature, which allows it to rapidly establish dominance in recently disturbed areas in the absence of effective brush management control. The field-based studies presented in this dissertation aim to assess innovative management strategies that may better prevent or hinder the progressive expansion of this problematic spiny succulent in these increasingly imperiled ecosystems. In particular, we examine the viability of prescribed fire as a catalyst to restore the ecological integrity of degraded rangeland ecosystems. The insights gained from this research should also improve our understanding of the successional dynamics and complex ecological processes that occur in these fire-dependent plant communities.