Herbaceous Response to Brush Management And Precipitation

1. Herbaceous Response to Brush Management And Precipitation Mr. Dean Keller, Dr. Steve Archer, Dr. Katharine Predick Dean.Keller@tusd1.org, iPlant Teacher Research Fellowship, University of Arizona, Tucson, Arizona, 85721 Background: ○ The proliferation of shrubs represents a threat to sustainable livestock production and grassland conservation. ○ Approaches for managing shrub abundance on rangelands include mechanical treatments, burning, and herbicide application. ○ Numerous studies have examined the herbaceous vegetation response to brush management, but as yet there has been no synthesis of outcomes. As a result, robust generalizations have yet to emerge. Objective :To synthesize reports of annual net herbaceous production (ANHP) response to various brush management techniques as a function of precipitation. Data: Outliers are highlighted in yellow. Results: ○herbaceous response to brush management was variable and not correlated with rainfall ○ 36 of 44 records showed an increase in ANHP regardless of brush management technique ○ 8 showed a decrease in ANHP ◦◦ 1 had data for 1 year only ◦◦ 2 were identified as outliers ◦◦ 3 showed a decrease in precipitation during year 3 ◦◦2 showed a trend of increasing ANHP ANHP vs. Precipitation • Applications: • Present iPlant research data to staff and parents of Cholla Magnet High School. • Discuss and plan for data-driven activities implementation with Math and Science staff. • Approach: • ○ reviewed the past 10 years of the Journal of Rangeland Management/ Rangeland Ecology and Management • ○ key word search of the University of Arizona library database [≈ 1200 articles] • ○ articles focused on mechanical techniques, burning, and use of herbicides • ○ 15 studies presenting data on herbaceous production and precipitation were used in the analysis Acknowledgements: I would like to thank the iPlant Program, Dr. Archer, and Dr. Predick for supporting me in this research.