Assessment of Tree Attributes and Understory Vegetation Composition Six Years Post-thinning in Redwood National Park (Northern CA, USA)

Coastal redwoods (Sequoia sempervirens) are a resilient tree species that once dominated coastal ecosystems. However, redwood forests have experienced numerous impacts compromising their health and vigor, which has led to greater competition from other tree species. Foresters and Ecologists are utilizing novel restoration strategies to conserve and recover redwood forests. This project’s objective was to assess tree attributes and understory composition six years after a restoration thinning treatment. The study took place in Redwood National Park in Orick, California along Holter Ridge Road at a site named Middle Fork Lost Man Creek. In 2015, a student capstone group from Humboldt State University collected data for three plots before and immediately after a thinning treatment. Six years later (2021), our capstone group resampled the data in these plots and added tree height and understory vegetation parameters. Results found that total basal area/acre increased from 205.4 in 2015 (post-thinning) to 215.0 in 2021 and the quadratic mean diameter increased from 17.5 inches in 2015 (post-thinning) to 18.9 inches in 2021. This project can serve as an example for future treatment in similar ecosystems and can potentially assist the recovery of secondary growth forests, while also assisting in connecting sections of Redwood National Park to promote redwood dominance

Assessment of Tree Attributes and Understory Vegetation Composition Six Years Post-thinning in Redwood National Park (Northern CA, USA)

ESM Senior Capstone Projec