Community-Scale Understanding of Biological Invasion Risks and Management Options in the Tucson, Arizona Wildland-Urban Interface

Author

Abigail Plecki, Southern Illinois University Carbondale

Date of Award

5-2020

Degree Name

Master of Science

Department

Forestry

First Advisor

Groninger, John

Second Advisor

Brenner, Jake

Third Advisor

Akamani, Kofi

Abstract

Buffelgrass (Cenchrus ciliaris) has been planted in the Tucson, Arizona area since the 1930s to address erosion control and grazing needs. Subsequently, buffelgrass spread has aggravated fire occurrence and intensity in the previously fire-less Sonoran Desert ecosystem. Buffelgrass also outcompetes native species in post-burn vegetation communities and represents a growing fire hazard to homeowners in the expanding Tucson wildland urban interface (WUI). Previous research indicates homeowners' lack of knowledge of changing wildland fire dynamics and the role played by buffelgrass. If WUI homeowners could better identify and understand the growing risk of buffelgrass, they could act to make their properties a defensive front against fires originating in buffelgrass-impacted urban areas. The purpose of this research was to assess the perceptions and responses of homeowners and public safety experts to buffelgrass invasion in Tucson. Better understanding the level of public knowledge of expanding buffelgrass impacts will help inform public awareness and cooperative action campaigns in the interest of promoting public safety and ecological integrity. We surveyed homeowners living within the Tucson WUI regarding their knowledge of buffelgrass occurrence, ecology and management options and compared respondents' answers to current practices recommended by buffelgrass experts. The resulting data were first explored using descriptive statistics, followed by multiple regression analysis to test hypotheses on the predictors of buffelgrass knowledge, level of concern for risks associated with the ongoing expansion of this species, and participation in buffelgrass control and fire wise actions. The results from the regression analysis showed that respondents' membership and leadership status in homeowner associations, both had a positive effect on involvement in buffelgrass control efforts while duration of residence in Tucson had a negative effect. Also, homeowners' level of concern about buffelgrass risks had a statistically significant negative effect on the total hours respondents spent controlling buffelgrass while the number of months respondents spent in Tucson per year had a negative effect. Moreover, respondents’ level of concern for risks involved with buffelgrass had a statistically significant positive effect on their participation in fire wise activities. Overall, these findings call to for target-specific educational programs for enhancing awareness and concern among newcomers and long-term residents in WUI communities about biological threats and other drivers of change, as well as the promotion of membership in local organizations aimed at responding to these drivers of change.