This is the position long held by Joel Trumbo, who has been promoted (he now oversees this position, so there is institutional knowledge). It is a key position for supporting invasive plant management on state wildlife areas and ecological reserves.

https://calcareers.ca.gov/CalHrPublic/Jobs/JobPosting.aspx?JobControlId=122123

Job Description and Duties

Under the general supervision of the Environmental Program Manager, Lands Program, the Senior Environmental Scientist is the lead scientist responsible for coordination of the DFW’s Integrated Pest Management (IPM) program. The Senior ES Specialist works independently, conducts complex, environmental assessments of fish and wildlife pest management problems, conducts extremely complex and difficult scientific investigations on pest management options and provides IPM recommendations for DFW-managed lands. The assessments and investigations require an understanding of the highly complex interactions of fish and wildlife ecology, pest biology, toxicology, and environmental chemistry.  The assessments conducted by the incumbent determine the most effective pest management strategies that are consistent with fish and wildlife conservation goals for the particular site and overall DFW policy.  IPM recommendations may include physical, cultural, biological and chemical control methods.