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The expansion of piñon-juniper woodlands the past 100 years in the western United States has resulted in large scale efforts to kill trees and recover sagebrush steppe rangelands. It is important to evaluate vegetation recovery following woodland control to develop best management practices. In this study, we compared two fuel reduction treatments and a cut-and-leave (CUT) treatment used to control western juniper (Juniperus occidentalis spp. occidentalis Hook.) of the northwestern United States. Treatments were; CUT, cut-and-broadcast burn (BURN), and cut-pile-and-burn the pile (PILE). A randomized complete block design was used with five replicates of each treatment located in a curl leaf mahogany (Cercocarpus ledifolius Nutt. ex Torr. & A. Gray)/mountain big sagebrush (Artemisia tridentata Nutt. spp. vaseyana (Rydb.) Beetle)/Idaho fescue (Festuca idahoensis Elmer) association. In 2010, 4 years after tree control the cover of perennial grasses (PG) [Sandberg's bluegrass (Poa secunda J. Pres) and large bunchgrasses] were about 4 and 5 % less, respectively, in the BURN (7.1 ± 0.6 %) than the PILE (11.4 ± 2.3 %) and CUT (12.4 ± 1.7 %) treatments (P < 0.0015). In 2010, cover of invasive cheatgrass (Bromus tectorum L.) was greater in the BURN (6.3 ± 1.0 %) and was 50 and 100 % greater than PILE and CUT treatments, respectively. However, the increase in perennial bunchgrass density and cover, despite cheatgrass in the BURN treatment, mean it unlikely that cheatgrass will persist as a major understory component. In the CUT treatment mahogany cover increased 12.5 % and density increased in from 172 ± 25 to 404 ± 123 trees/ha. Burning, killed most or all of the adult mahogany, and mahogany recovery consisted of 100 and 67 % seedlings in the PILE and BURN treatments, respectively. After treatment, juniper presence from untreated small trees (<1 m tall; PILE and CUT treatments) and seedling emergence (all treatments) represented 25-33 % of pre-treatment tree density. To maintain recovery of herbaceous, shrub, and mahogany species additional control of reestablished juniper will be necessary.

Sagebrush cover is often estimated with the use of the line intercept method. However, a lack of standardized protocols may lead to variable estimates of sagebrush canopy cover. Our objectives were to determine the influence of gap size on 1) sagebrush canopy cover estimates, 2) time needed to read a transect, and 3) among-observer variability in sagebrush canopy cover estimates. We utilized 5-, 10-, and 15-cm gaps, and defined a gap as a lack of continuous live or dead shrub canopy. In instances where a segment of dead cover was less than the gap size and adjoined live cover, the dead cover was measured as live. We evaluated canopy cover at 6 Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. Wyomingensis Beetle & A. Young) sites in southeast Oregon. At each site, four 2-person teams measured sagebrush canopy intercept along 50-m transects. Each transect was read by multiple teams to allow for assessment of among-observer variability. Intercept values were converted to percent canopy cover and we used analysis of variance to determine the influence of site and gap size on measurement time and cover estimates. Observer variability was highest at the intermediate gap size (i.e., 10 cm). Transect measurement time was longest with the use of a 5-cm gap (P , 0.001). Total cover estimates were not related to gap size (P ¼ 0.270). Live canopy cover estimates increased (P , 0.001) from 12.1% to 14.5% with increasing gap size, and cover of dead material decreased (P ¼ 0.015) from 4.4% to 3.2%. These differences are small in magnitude and would not likely change a gross assessment of vegetation status. However, use of a standardized gap size will enhance comparability of canopy cover estimates among studies and will decrease between-year sampling error for repeat monitoring. Resumen La cobertura de ''Sagebrush'' a menudo es estimada usando el método de línea de intercepció n, sin embargo, la falta de protocolos estandarizados puede conducir a estimaciones variables de la cobertura de copa del ''Sagebrush.'' Nuestros objetivos fueron determinar la influencia del tamañ o del hueco en: 1) las estimaciones de la cobertura de copa del ''Sagebrush,'' 2) el tiempo necesitado para leer el transecto, y 3) la variabilidad entre observadores en la estimació n de la cobertura de copa del ''Sagebrush.'' Utilizamos huecos de 5, 10, y 15 cm y definimos un ''hueco'' como la falta de continuidad de la copa, viva o muerta, del ''Sagebrush.'' En los casos donde un segmento de cobertura muerta, adyacente a cobertura viva, era de menor tamañ o que el hueco este se midió como cobertura viva. Evaluamos la cobertura de copa en seis sitios de ''Wyoming big sagebrush'' (Artemisia tridentata Nutt. ssp. Wyomingensis Beetle & A. Young) en el sudeste de Oregon. En cada sitio, cuatro equipos de dos personas midieron la intercepció n de la copa del ''Sagebrush'' a lo largo de transectos de 50 m. Cada transecto fue leído por los diferentes equipos para evaluar la variabilidad entre observadores. Los valores de intercepció n fueron convertidos a % de ...