Effects of Biochar on Short-Term Growth in Pinus contorta var. latifolia

Rocky Mountain lodgepole pine (Pinus contorta var. latifolia) is a fire-adapted pine species that has evolved to survive a fire with serotinous cones that open to release seeds at specific temperatures. However, the increased intensity and frequency of modern wildfires has led to decreased germination of lodgepole pines, and recent widespread drought has weakened the immune systems of lodgepole pine, causing increased infestation of mountain pine beetle. As a result, there is a need for improved forest regeneration techniques in lodgepole pine forests. One method of improving revegetation could be through use of a biochar, a carbon-based substance that is produced when woody biomass is burned in a high temperature environment. Numerous studies have found that biochar has generally positive impacts on soil health and plant productivity. However, more research is needed on its impact on native plants, especially lodgepole pine and other species with serotinous mechanisms.

This study looks to address how different applications of biochar can be utilized in early greenhouse growth of lodgepole pine, the primary step of many revegetation efforts. In the Olin Hall Greenhouse, following a stratification process, we compared the 6-month growth of lodgepole pine seeds sown in potting soil, potting soil incorporated with biochar, and biochar on top of potting soil. Our procedure is based on protocols developed by the Colorado State Forest Service nursery, the Native Plant Network, U.S. Forest Service, and other academic studies. In our observations 3 months following germination, soil plots with biochar amendments were more successful in promoting plant mass growth of lodgepole pine. After the full 6-month growing period concluded, we found that soil plots with biochar amendments were more successful in promoting shoot height growth of lodgepole pine. These results hold potentially valuable implications on revegetation efforts for an ecosystem increasingly challenged by a changing climate.