Date of Award


Degree Name

MS in Environmental Sciences and Management


Natural Resources Management


College of Agriculture, Food, and Environmental Sciences


Yamina Pressler

Advisor Department

Natural Resources Management

Advisor College

College of Agriculture, Food, and Environmental Sciences


Santa Rita Ranch is a 1,750-acre cattle ranch in Templeton, California, that was privately owned and continuously grazed for the past 70 years. In 2021, The Land Conservancy of San Luis Obispo (LCSLO) acquired the property, and in the winter of 2022, they built a fence that bisects the ranch, excluding the cattle from 800 acres to preserve the riparian habitat. The LCSLO is currently defining the ecological baseline for the ranch to inform future management decisions. Given that cattle grazing has many environmental tradeoffs, they wanted to establish a long-term monitoring study to understand how relieving the pressures of grazing impacts plant community composition within the grasslands of Santa Rita Ranch. We established monitoring sites with comparable soil types, topography, and vegetation on the grazed and ungrazed sides of the ranch. We collected the first year of data in the spring of 2023 using the California Native Plant Society’s Relevé vegetation sampling technique. In addition, we sampled above and belowground biomass from the grazed and ungrazed sites to study the impacts cattle have on community plant biomass, particularly root biomass and percent moisture. The early findings revealed no significant differences between the plant community composition of the grazed and ungrazed monitoring sites, likely because the cattle had only been excluded for six months, and monitoring studies have extended time frames before any correlation between variables can be detected. We did find a statistical difference between grazed aboveground and belowground plant biomass. However, the two treatments had no significant difference between the average belowground biomass. Site-specific ecological data is often limited; therefore, another objective of this project was to bridge the communication gap between stakeholders by making the data from this study and other student research projects at Santa Rita Ranch accessible online at The hope behind this project is that researchers will continue monitoring and land managers will use the information to help them develop land management strategies that enhance plant diversity, increase soil health, and maintain ecosystem multi-functionality.