Techniques for triggering germination of Adenostoma fasciculatum in revegetation projects at Rocky Canyon Quarry

• Main Author: Scolari, Stephanie B
• Format: Others
• Published: DigitalCommons@CalPoly 2009
• Subjects: Plant Biology
• Online Access: https://digitalcommons.calpoly.edu/theses/216; https://digitalcommons.calpoly.edu/cgi/viewcontent.cgi?article=1223&context=theses

Rocky Canyon Quarry is a granite mine located in the Santa Lucia Mountains about 5 miles southeast of the city of Atascadero. The Surface Mining and Reclamation Act (SMARA), which passed in 1975, dictates that California mines must rehabilitate lands disturbed by mining operations. Dr. V. L. Holland and his students in the Biological Sciences Department at California Polytechnic State University, San Luis Obispo (Cal Poly) have been working on restoration and revegetation of the Rocky Canyon Quarry since the early 1990’s. Adenostoma fasciculatum (chamise) dominates the chaparral communities (chamisal chaparral) found in Rocky Canyon. Chamise is the most common shrub in much of California’s chaparral and is adapted to recovery after fires by both seed germination and lignotuber sprouting. In laboratory and greenhouse experiments, it has been shown that chamise seeds have an increased germination rate when subjected to fire related stimulates such as heat, smoke, and charate. The goal of my research, which was conducted over a two year period (2002-2004), is to find successful, inexpensive techniques to restore chamisal chaparral on the mined granite slopes of Rocky Canyon Quarry. My study focused on examining and comparing the different techniques that have been shown by other researchers in laboratory and greenhouse situations to increase the germination rate of chamise. I compared the effects of heat, sulfuric acid, powdered charred wood (charate), and smoke on the germination of chamise seeds under the natural field conditions found in the Rocky Canyon Granite Quarry. Seeds were subjected to between one and four of these treatments, to examine possible interactive effects amongst the treatments, and then placed in plots containing the topsoil used to restore the mined hillsides. Plots remained under natural field conditions, and seedlings were counted following emergence. Results of my studies indicate that the smoke related treatments of liquid smoke and chamise smoke have the greatest effect in increasing the seed germination rate of chamise and that there is little to no benefit in subjecting chamise seeds to more than one treatment.