Submitted to: Western North American Naturalist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/10/2021
Publication Date: N/A
Interpretive Summary: We evaluated plant community succession following prescribed fire low sagebrush steppe in southeastern Oregon, comparing herbaceous yield, vegetation canopy cover and density compared between burned and unburned treatments (2012-2020). Herbaceous yield in the Burn treatment was about double the Control for most of the post-fire period. Both burned and unburned low sagebrush treatments were dominated by perennial grasses and forbs and burned sites exhibited high levels of ecological resilience and resistance to weed invasion.
Technical Abstract: We evaluated plant community succession following prescribed fire on Artemisia arbuscula var. arbuscula Nutt. McMinn (low sagebrush) steppe in southeastern Oregon. Treatments were prescribed burned (Burn; fall 2012) and unburned (Control) A. arbuscula steppe and the study design was a randomized complete block with four replicates per treatment. Herbaceous yield, vegetation canopy cover and density were compared between treatments (2012-2020). Fire practically eliminated A. arbuscula and there was no recruitment of new plants the first eight years after prescribed burning. Herbaceous yield in the Burn treatment was about double the Control for most of the post-fire period. Native perennial grasses and forbs comprised 94 to 96 % and Bromus tectorum L. (cheatgrass) 0.2 to 2% of total herbaceous yield in the Control. In the Burn treatment, perennial grasses and forbs comprised 83 to 87 %, native annual forbs 2 to 5 %, and B. tectorum 3 to 9 % of total herbaceous yield. Despite an increase in B. tectorum, the burned A. arbuscula sites were dominated by herbaceous perennial grasses and forbs and exhibited high levels of resilience and resistance. For these sites, and comparable A. arbuscula associations, weed control or seeding are unlikely to be needed, post-fire, to recover the native herbaceous community.