Author
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Submitted to: Restoration Ecology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/25/2016 Publication Date: 1/11/2017 Citation: Davies, K.W., Bates, J.D. 2017. Restoring big sagebrush after controlling encroaching western juniper with fire: aspect and subspecies effects. Restoration Ecology. 25:33-41. Interpretive Summary: Restoration of mountain big sagebrush after controlling encroaching western juniper with fire is needed to improve wildlife habitat. We evaluated seeding mountain and Wyoming big sagebrush on north and south aspects after juniper control with prescribed burning. We included seeding Wyoming big sagebrush, a more drought tolerant subspecies of big sagebrush, because it might grow better than mountain big sagebrush on hot, dry south slopes or during drought. Seeding mountain big sagebrush generally increased sagebrush cover and density compared to unseeded controls and seeding Wyoming big sagebrush. Sagebrush cover and density was generally greater on north compared to south aspects, suggesting that post-fire sagebrush recovery, with and without seeding, will be variable across the landscape based on topography. This study suggests that seeding sagebrush after controlling junipers with burning accelerates sagebrush recovery. Technical Abstract: The need for restoration of shrubs is increasingly recognized around the world. In the western USA, restoration of mountain big sagebrush (Artemisia tridentata Nutt. ssp. vaseyana (Rydb.) Beetle) after controlling encroaching conifers is a priority to improve sagebrush-associated wildlife habitat. Conifers can be cost-effectively removed with prescribed burning when sagebrush is co-dominant; however, burning removes sagebrush and natural recovery may be slow. We evaluated seeding mountain and Wyoming big sagebrush (A. tridentata Nutt. ssp. wyomingensis Beetle & Young) on north and south aspects after conifer control with prescribed burning. We included seeding Wyoming big sagebrush, a more drought tolerant subspecies of big sagebrush, because it might grow better than mountain big sagebrush on hot, dry south slopes or during drought. Seeding mountain big sagebrush increased sagebrush cover and density compared to unseeded controls. In mountain big sagebrush seeded plots, sagebrush cover was 19 times greater on north compared to south aspects at the conclusion of the study. By the fourth year post-seeding, sagebrush cover was greater on mountain compared to Wyoming big sagebrush seeded plots on both aspects. Natural recovery of sagebrush was occurring on north aspects with sagebrush cover averaging 3% four years post-fire. Sagebrush was not detected on south aspects in unseeded controls at the end of the study. These results suggest that post-fire sagebrush recovery, with and without seeding, will be variable across the landscape based on topography. This study suggests that seeding sagebrush after controlling conifers with burning accelerates sagebrush recovery. |
