Overview

Data was collected in the field by team members systematically going through sections of the Thurston Hills Natural Area to evaluate Oregon white oak habitat. All mature oaks (greater than 12 inches in diameter) within the study area were marked with a Global Positioning System (GPS) waypoint, and evaluated according to a series of attributes. This information was later analyzed quantitatively and spatially and presented in usable format for future management decisions.

For each mature oak, recorded data included diameter at breast height (DBH), crown shape and fullness, relative dominance compared to nearby trees, health status, and presence of suppressing conifers. The team also recorded observations on slope, aspect, and access distance from the nearest trail. Observations that were relevant to restoration and recreation management such as other nearby native plants, assessment of terrain (i.e. rocky, steep slopes, closest access to nearest established paths, etc.), as well as the presence and quantity of invasive species (i.e. blackberries, etc.) was made note of. The information collected was used to assign each oak an overall management priority level ranging from low priority to urgent priority.

Forestry tools and equipment were used in data collection including Diameter Tape, Biltmore sticks, Clinometers , and compasses.

Field Data Collection

The following map observed below show how study sites were divided into smaller sections for efficiency. Each of these tracts were surveyed by three teams of data collectors, moving along the red, blue, and midlines respectively. Teams used Avenza georeferenced pdf maps, accessable on mobile smartphones, and communication to keep track of their relative locations and ensure that all trees were documented without duplication. One team moved with the red line, one with the blue line, and one surveyed down the middle.