Post-wildfire seeding to restore native vegetation and limit exotic annuals: an evaluation in juniper-dominated sagebrush steppe

Authors: Davies, Kirk; Bates, Jonathan - Jon; Boyd, Chad

Submitted to: Restoration Ecology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/13/2018
Publication Date: 1/25/2019
Citation: Davies, K.W., Bates, J.D., Boyd, C.S. 2019. Post-wildfire seeding to restore native vegetation and limit exotic annuals: an evaluation in juniper-dominated sagebrush steppe. Restoration Ecology. 27(1):120-127. https://doi.org/10.1111/rec.12848.
DOI: https://doi.org/10.1111/rec.12848

Interpretive Summary: Reestablishment of perennial vegetation may be need after wildfires to limit exotic species in juniper-dominated sagebrush communities. We evaluated broadcast seeding native perennial grasses and mountain big sagebrush after wildfires in six juniper-dominated sagebrush communities. Seeding native perennial species increased perennial grass and sagebrush and reduced exotic annual grasses. Seeded areas were perennial-dominated and non-seeded areas were annual-dominated at the end of the study. This suggest that perennial vegetation should be seeded after wildfires in juniper-dominated sagebrush communities.

Technical Abstract: Reestablishment of perennial vegetation is often need after wildfires to limit exotic species and restore ecosystem services. Some ecosystems, however, are resilient to disturbance and resistant to exotic plant invasions and do not require restoration efforts. If restoration is needed, an additional concern is if seeding native perennial vegetation can achieve management objectives of increasing perennial vegetation and limiting exotic vegetation. We evaluated broadcast seeding native perennial grasses and mountain big sagebrush (Artemisia tridentata Nutt. spp. vaseyana (Rydb.) Beetle) after wildfires in six juniper (Juniperus occidentalis ssp. occidentalis Hook)-dominated mountain big sagebrush communities. Seeding native perennial species increased perennial grass and sagebrush cover and density. Perennial grass cover was 4.3 times greater in seeded compared to non-seeded areas. Sagebrush cover averaged 24% and < 0.1% in seeded and non-seeded areas at the conclusion of the study (three years post-fire), respectively. Seeding perennial species reduced exotic annual grass and annual forb cover and density. Exotic annual grass cover was 8.6 times greater in non-seeded compared to seeded areas three years post-fire. Exotic annual grass cover increased over time in non-seeded areas, but decreased in seeded areas by the third year post-fire. Seeded areas were perennial-dominated and non-seeded areas were annual-dominated at the end of the study. These results imply that juniper-dominated sagebrush communities may need restoration after burning. Establishing perennial vegetation may be critical after wildfires in juniper-dominated sagebrush steppe to prevent the development of annual-dominated communities.