Many drylands have been converted from perennial‐dominated ecosystems to invaded, annual‐dominated, fire‐prone systems. Innovative approaches are needed to disrupt fire‐invasion feedbacks. Targeted grazing can reduce invasive plant abundance and associated flammable fuels, and fuelbreaks can limit fire spread. Restored strips of native plants (native greenstrips) can function as fuelbreaks while also providing forage and habitat benefits. However, methods for establishing native greenstrips in invaded drylands are poorly developed. Moreover, if fuels reduction and greenstrip establishment are to proceed simultaneously, it is critical to understand how targeted grazing interacts with plant establishment. We determined how targeted grazing treatments interacted with seed rate, spatial planting arrangement (mixtures vs. monoculture strips), seed coating technology, and species identity (five native grasses) to affect standing biomass and seeded plant density in experimental greenstrips. We monitored for two growing seasons to document effects during the seedling establishment phase. Across planting treatments, ungrazed paddocks had the highest second‐year seeded plant densities and the highest standing biomass. Paddocks grazed in fall of the second growing season had fewer seedlings than paddocks grazed in spring, five months later. High seed rates minimized negative effects of grazing on plant establishment. Among seeded species, Elymus trachycaulus and Poa secunda had the highest second‐year densities, but achieved this via different pathways. Elymus trachycaulus produced the most first‐year seedlings, but declined in response to grazing, whereas P. secunda had moderate first‐year establishment but high survival across grazing treatments. We identified clear tradeoffs between reducing fuel loads and establishing native plants in invaded sagebrush steppe; similar tradeoffs may exist in other invaded drylands. In our system, tradeoffs were minimized by boosting seed rates, using grazing‐tolerant species, and delaying grazing. In invaded ecosystems, combining targeted grazing with high‐input restoration may create opportunities to limit wildfire risk while also shifting vegetation toward more desirable species.

The Nevada Plots exclosure system was constructed in 1937 following passage of the Taylor Grazing Act to assess long-term effects of livestock grazing on Nevada rangelands. A comparison of vegetation characteristics inside and outside exclosures was conducted during 2001 and 2002 at 16 sites. Data analysis was performed with a paired t test. Out of 238 cover and density comparisons between inside and outside exclosures at each site, 34 (14% of total) were different (P < 0.05). Generally, where differences occurred, basal and canopy cover were greater inside exclosures and density was greater outside. Shrubs were taller inside exclosures at 3 sites grazed by sheep (Ovis aries). Perennial grasses showed no vertical height difference. Aboveground plant biomass production was different at only 1 site. Plant community diversity inside and outside exclosures were equal at 11 of 16 sites. Species richness was similar at all sites and never varied > 4 species at any site. Few changes in species composition, cover, density, and production inside and outside exclosures have occurred in 65 years, indicating that recovery rates since pre Taylor Grazing Act conditions were similar under moderate grazing and grazing exclusion on these exclosure sites. Resumen El sistema de exclusiones de Nevada se construyó en 1937, después de ser aprobada el Acta Taylor de Apacentamiento, para evaluar los efectos a largo plazo del apacentamiento del ganado sobre los pastizales de Nevada. Durante los años 2001 y 2002, en 16 sitios se condujo una comparación de las características de la vegetación dentro y fuera de las exclusiones. El análisis de los datos se llevo a cabo mediante pruebas de t-student para muestras apareadas. De 238 comparaciones de cobertura y densidad de la vegetación dentro y fuera de las exclusiones, 34 de ellas (14% del total) fueron diferentes (P < 0.05). Generalmente, donde ocurrieron las diferencias, la cobertura basal y de la copa fueron mayores dentro de las exclusiones y la densidad fue mayor fuera de ellas. En tres sitios apacentados con ovinos (Ovis aries) los arbustos fueron mas altos dentro de las exclusiones. Los zacates perennes no mostraron diferencias verticales de altura. La producción de biomasa vegetal aérea fue diferente solo en un sitio. La diversidad de la comunidad vegetal dentro y fuera de las exclusiones fue igual en 11 de los 16 sitios. La riqueza de especies fue similar en todos los sitios y nunca varió por más de 4 especies en ninguno de ellos. Pocos cambios han ocurrido en 65 años en la composición de especies, cobertura, densidad y producción dentro y fuera de las exclusiones, indicando que en estos sitos de exclusión las tasas de recuperación anteriores a las condiciones establecidas por el Acta Taylor fueron similares bajo un apacentamiento moderado y la exclusión al apacentamiento.

Previous research suggested that big sagebrush (Artemisia tridentata Nutt.) recruitment occurs in pulses consistent with favorable climatic conditions. In 1997, 75 stem sections were collected from 9 stands of each of the 3 subspecies of big sagebrush in Wyoming along elevation and climatic gradients. Annual growth rings were used to identify the year plants were established. Large cohorts of Wyoming big sagebrush (A. tridentata ssp.

Management of soils on areas subjected to planned disturbance, such as surface mine sites, is crucial to post-disturbance restoration. We conducted a study to determine which of the following two topsoil management strategies resulted in less of a negative impact to the soil and vegetation resources and better promoted site restoration on in situ uranium wellfields: (1) removal of topsoil from an entire wellfield and stockpiling until mining activity is complete; or (2) leaving the majority of topsoil on the wellfield and allowing it to be exposed to disturbance associated with wellfield development activity (primarily heavy vehicle traffic). Our study compared selected soil properties from areas on in situ uranium wellfields managed by the two strategies stated above and with adjacent, relatively undisturbed sites. Vegetation reestablishment was assessed on sites where topsoil was left in place. Results indicated that levels of vehicular traffic on wellfields did not cause significant soil compaction and that removal and stockpiling of topsoil results in more negative impacts than disturbance inflicted when topsoil is left in place.

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