The invasive annual grass, medusahead, infests rangelands throughout the West, from the Columbia Plateau to the California Annual Grasslands and the Great Basin. Dominating secondary succession in the sagebrush steppe, medusahead can degrade the habitat of threatened species such as the greater sage-grouse. This research explores the potential of dormant season grazing as an applied management strategy to reduce the negative impacts of medusahead while promoting recovery of perennial vegetation at the landscape scale. In particular, it assessed grazing with four treatments from 2018 to 2020: traditional grazing (May–October), dormant season grazing (October–February), traditional + dormant season grazing (May–February), and no grazing. After 2 yr of grazing treatments, biomass, density, cover, and fuel continuity did not differ between treatments (P > 0.05). However, biomass measurements were significantly different between years, which is likely due to greater than normal precipitation in 2019 and 2020. Between 2018 and 2019, annual grass biomass increased by 81% (666–1 212 kg ha⁻¹) and perennial grass biomass increased by 165% (118–313 kg ha⁻¹). Litter biomass decreased by approximately 15% in every year since 2018 (2 374, 2 012, and 1 678 kg ha⁻¹ in 2018–2020). There were not significant differences in cover or density of annual and perennial grasses between treatments and years. Our results indicate that 2 yr may not be adequate time for dormant season grazing treatments to be effective in reducing the abundance of medusahead and that after 2 yr of treatments, dormant season grazing does not have a detrimental effect on perennial vegetation.

入侵性一年生草，水母，侵扰整个西部的牧场，从哥伦比亚高原到加利福尼亚一年生草原和大盆地。水母在鼠尾草草原的次生演替中占主导地位，它会降低鼠尾草等受威胁物种的栖息地。这项研究探讨了休眠季节的潜力放牧作为一种应用管理策略，可减少水母的负面影响，同时促进景观尺度上多年生植被的恢复。特别是，它评估了2018年至2020年四种放牧方式：传统放牧（5月至10月）、休眠期放牧（10月至2月）、传统+休眠期放牧（5月至2月）和不放牧。经过 2 年的放牧处理后，处理之间的生物量、密度、覆盖度和燃料连续性没有差异（ P> 0.05）。然而，各年生物量测量结果存在显着差异，这可能是由于 2019 年和 2020 年降水量高于正常水平。2018 年至 2019 年，年牧草生物量增加了 81%（666–1 212 kg ha −1^））和多年生草生物量增加了 165%（118–313 kg ha ⁻¹）。自2018年以来，凋落物生物量每年减少约15%（2018-2020年分别为2 374、2 012和1 678 kg ha ⁻¹）。处理和年份之间一年生和多年生草的覆盖度或密度没有显着差异。我们的结果表明，2 年的休眠季节放牧处理可能不足以有效减少水母的丰度，并且经过 2 年的处理后，休眠季节放牧不会对多年生植被产生不利影响。