Sagebrush steppe vegetation monitoring in the Clarno Unit of the John Day Fossil Beds National Monument: 2017 annual report

Smith, Kelly; Bylund, Alephair; Robson, Ellen; Maass, Erik

As part of the Upper Columbia Basin Network sagebrush steppe vital signs monitoring program, a survey of sagebrush steppe ecological condition was conducted in early June 2017 within the Clarno Unit of John Day Fossil Beds National Monument (JODA) following methods outlined in the UCBN sagebrush steppe monitoring protocol (Yeo et al. 2009). Cover of exposed soil and of principal native and non-native plants or genera were estimated in 217 1 m2 quadrats randomly placed throughout the sampling frame. The entire unit has been surveyed in May and June each year since 2011. These survey efforts were outside of the UCBN’s 3-year revisit plan, in response to the August 2011 wildfire that swept through the Clarno Unit. Approximately 98% of the vegetated portion of the unit was burned by this fire. Previous wildfires swept the monument in 1985, 1994, and 1995. The entire Monument, including the Clarno Unit, was surveyed during May-June, 2011, as part of the regular 3-year revisit schedule (Yeo and Rodhouse 2012). This created an excellent opportunity to study fire effects in Clarno. This report briefly describes the findings from 2017, and provides some comparisons in the abundances of key principal species of interest with 2011-2016 observations. This report provides some insights into the effects of the fire on the Monument’s upland plant communities, a topic of critical importance to park management. Cheatgrass (Bromus tectorum) and medusahead (Elymus caput-medusae) species continue to dominate much of the Clarno landscape, and medusahead presents a major threat to the ecological integrity of the unit. Big sagebrush (Artemisia tridentata) was not recorded in any of the 2017 plots (n=215), and many areas that once supported sagebrush (i.e., sage habitat category) have remained shrub cover free since the 2011 wildfire. Cover of native bunchgrasses, which define the steppe aspect of sagebrush steppe, has remained at low to moderate cover. Principal native bunchgrasses included in the study were: bluebunch wheatgrass (Pseudoroegneria spicata), Sandberg bluegrass (Poa secunda), needlegrasses (Stipa spp.), and sand dropseed (Sporobolus cryptandrus). Bluebunch wheatgrass, a foundation species in the Clarno landscape, was distributed at prefire levels in 2017 compared with initial post fire conditions. Overall, species appeared to have suffered relatively low mortality from the fire (Esposito et al. 2012), with plot cover levels in 2017 at >25% comparable to those prior to the 2011 fire. Native forb cover generally was low. Principal native forb species included: milk-vetch (Astragalus spp.), yarrow (Achillea millefolium), buckwheats (Eriogonum spp.), Blue Mountain prairie clover (Dalea ornata) and desert parsley (Lomatium spp.). Yarrow was the most abundant native forb encountered. Filaree (Erodium cicutarium), a non-native forb, was widespread, seen at low occurrences nearly ubiquitously throughout the unit, as well as in dense patches in association with medusahead on flat benches. As is typical of the heterogeneous landscape of JODA, some of the Clarno plots represent good range condition although most of the plots indicate degraded conditions.

Sagebrush steppe vegetation monitoring in the Clarno Unit of the John Day Fossil Beds National Monument: 2017 annual report

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