Dr. Pierson's areas of research include plant-microbe interactions, biological control, and sustainable agriculture. She also conducts research related to zebra chip disease of potato, microbe-insect interactions, and terrestrial plant ecology. She teaches the undergraduate course Garden Science and the graduate course Plant-associated Microorganisms, which is available to students in three different graduate programs. Dr. Pierson is active in graduate education, currently serving as a member of the Horticultural Sciences Graduate Program Committee and the MEPS admissions committee and as the advisor for the Horticulture Graduate Council. She also serves as a chair or member of graduate research committees and provides undergraduate laboratory research experience.