While attending Humboldt State University College for her Masters in Biology, Susie Van Kirk also worked with other environmental activists like Lucille Vinyard; the two having played roles in establishing what is now the Redwood National Park in 1968. Working with the Sierra club, and other organisations Susie soon made a name for herself, being on the first board of directors of the Westcoast Environmental Center in 1971.
In 1972, Susie helped lead the Stop-at-Four Committee, composed mostly of students, in a petition to stop the expansion of the highway bisecting Arcata from the previous four lanes which were completed in 1954 to a proposed six lanes. This renovation would require the removal of 200 homes in addition to both direct and indirect environmental impacts. Continuing her environmental work with the Sierra Club. Susie would be a long time advocate of the Redwoods.
Over the years, Susie Van Kirk had grown to be something of a renowned local historian. Her personal research through archived newspapers, journals, reports, and person interviews cemented the foundation of credibility while her thorough and meticulous work built her a strong reputation as a historian. She worked on numerous projects within the Redwood National Park borders, even writing a brief historic summary of Redwood Creek.
Among her other professional works, Susie worked as a consultant and would generate environmental impact reports. These documents are critical in the construction of public roadways or utilities and ensure that their implementation doesn’t have any overwhelming negative effects.