INTEGRATE VEGETATIVE BUD-BASED PROPAGATION AND SEEDS IN RESTORATION OF RANGELAND NATIVE PLANT COMMUNITIES

The primary research goal of this project is to improve upon our previous systems approach to restore annual-grass-affected rangeland systems in the sagebrush steppe of North America. In 2013, we developed a systems approach that advanced ecological restoration practices from conceptual and phenomenological descriptions to quantitative process-based models that can be used to address specific applied questions. Our systems approach uses life history information to identify transitions from plant establishment through maturation and reproduction and links those transitions to the management of the ecological processes driving establishment and population growth. In our prior NP 304 project (July, 2015 to August, 2020), we are incorporating the effects of seed quality, safe-site availability, and seedling defoliation effects into our systems model for forecasting vegetation dynamics of sagebrush steppe ecosystems and are incorporating these factors into decision-support tools to guide managers in their planning and management. It is nearly impossible to reestablish native species from seeds in annual-grass invaded sagebrush steppe because seedlings struggle to break through the soil crust and survive the pulses of harsh weather conditions during establishment. In this project, we will test the potential to use growth buds harvested from crowns of native species to augment seed-based restoration efforts. Our pilot data suggests that plants growing from crown pieces that contain buds and growth primordia emerge faster than seedlings. The more substantial carbohydrate reserves of buds/primordia as compared to seeds may confer increased ability to survive harsh climatic conditions, such as those imposed by wet/dry weather pulses. Our objectives in the current project are to add critical information to our life history forecasting models and potentially provide a novel approach to restoring invaded sagebrush steppe ecosystems. Specifically, during the next five years, we will focus on the following: Objective 1: Develop methods for harvesting, excavating, and storing buds and/or growth primordia and determine if buds and/or primordia (growth tissue around buds) of key caespitose grasses regenerate when placed in soil under near optimal conditions. Objective 2: Quantify the environmental conditions under which buds/primordia outperform the emergence and growth of plants grown from seeds and assess the fitness (reproduction) of buds/primordia with and without seeds in comparison to seeds alone at several sites throughout the Great Basin. Objective 3: Determine the physiological responses of buds/primordia and seeds to characterize the actual mechanism for enhanced or weakened emergence and/or survival during restoration. Sub-objective 3A: Quantify and contrast the life histories of planted buds versus seeds. Sub-objective 3B: Evaluate the physiological characteristics of plants established from buds versus seeds during restoration.