Clark’s research concerns how the post-disturbance environment influences understory plant communities. His current work focuses on how understory plant diversity varies across the spectrum of fire severity classes and in response to interactions with Ceanothus and other ecological features associated with the post-fire environment of mixed-conifer forests in the Sierra Nevada. His work also seeks to examine Ceanothus response to wildfire severity through functional trait variation. Clark served as a Peace Corps volunteer in the Philippines and assisted fishing communities with coastal resource management as well as organized college students to teach environmental stewardship and climate change awareness in elementary schools. His Master’s research at Sonoma State University focused on plant-plant interactions and plant functional trait response to large mammal (tule elk) herbivory in coastal prairie grasslands.