Experiment of Pest Treatment Methods on Carex obnupta

Experiment of Pest Treatment on Carex obnupta – Alexandria Crabtree (Spring 2023) 

Carex obnupta, also known as Slough Sedge, is a robust obligate wetland sedge native to the Pacific Northwest (1). Slough Sedge provides ecosystem benefits to wetlands such as erosion control, streambank stabilization, water filtration, and wildlife habitat (1), so it is a great option for restoration efforts. At SER-UW Native Plant Nursery, Carex is grown inside the hoophouse and is currently suffering from aggressive pest infestations, most notably, aphids. Due to the dense arrangement of leaves near the base of the plant, Carex many pests can easily hide and evade treatment. Our current pest control method at the nursery includes the application of neem oil. This experiment tests the effects of high and low dilutions of 70% neem oil as well as a soap treatment on Slough Sedge plants at a once-per-week spray interval. Results of this experiment will not only be important in testing the pest control efficacy of different neem oil concentrations but could also be informative of concentrations to avoid to protect the leaves of the plant (2).