Site Prioritization for the Treatment of Invasive Arundo donax in the Pedernales Watershed in Central Texas

Abstract

Arundo donax, commonly known as Giant Reed, is an invasive species of growing concern in the Central Texas Hill Country ecoregion. A. donax is an aggressive invader of riparian zones; it crowds out native streambank vegetation, disrupts floodplain function, and causes excessive evapotranspiration. In an effort to control the spread of A. donax, the Texas Parks and Wildlife Department (TPWD) has collaborated with nonprofit organizations to create the Healthy Creeks Initiative (HCI), which is currently active in the Pedernales and Blanco watersheds. Through HCI, TPWD and its partners enroll private landowners into a voluntary program that provides free herbicidal treatment for A. donax. This analysis provides a framework for prioritizing the treatment process based on A. donax biology and treatment efficiency. I applied several different weighting schemes to the prioritization model, and used it to analyze both enrolled parcels. These analyses resulted in different distributions of treatment priority. The end product is a flexible model that can be used as HCI efforts continue in the Pedernales watershed and beyond.