Lilly Sencenbaugh

Research Overview:

Effectiveness of traditional and novel management control strategies on Ventenata dubia and Bromus tectorum.

Bromus tectorum is an invasive winter annual grass that has been found in the United States since the mid-1800s. It has been recognized as a problem in disturbed western rangelands for some time. Ventenata dubia is an invasive winter annual grass that was first identified in the United States in the 1950s and is becoming more of a problem in western Montana. It is found in open disturbed regions, particularly areas where Bromus tectorum is also found. These species are problems in rangelands as they quickly dominate areas and can alter ecosystem functions. Bromus tectorum is a pervasive species requiring effective control strategies, while Ventenata dubia is a relatively new problem, so it is of vital importance we determine effective control strategies.  

My goal is to determine the best management practices to control these invasive annual grasses. I will do this through determining the effectiveness of current herbicide approaches for reducing the abundance of target species and recovery of desired species. I will be revisiting sites that were sprayed with the herbicide Indaziflam in 2016 and a split treatment spray in the summer of 2020. I will monitor these sites for V. dubia abundance and plant community changes over time. Then I will analyze different novel weed control strategies for their effectiveness at removing the target invasive species and changes to the plant community. My first novel strategy is using Brassica juncea (Indian Mustard) by-products as biofumigants to remove the target invasive species. These products should suppress germination in the invasive species, allowing the native species to recover. My next novel strategy is the soil amendment Edaphix, which promotes the growth of native perennials, thereby suppressing the growth of invasive annuals. These strategies will be analyzed and compared via greenhouse and field experiments.