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Item Effect of Livestock Species on Floral Resources and Pollinators in Low-Diversity Grasslands(North Dakota State University, 2020) Cutter, Jasmine Antonia VillamarinLivestock management influences the extent to which grazing lands provide resources for native species. We compared how livestock species – sheep or cattle – affected floral resources and bee and butterfly communities in low-diversity, post-Conservation Reserve Program (CRP) pastures managed with patch-burning. We sampled bees and butterflies three times per season 2017-2019 and counted flowering stems within 1 m of transects. Pastures grazed by sheep had significantly fewer flowers and significantly lower floral richness than cattle pastures. Native bees were three to sixteen times more abundant in cattle pastures compared to sheep. Butterfly communities were similar between grazing treatments, because agricultural-tolerant, habitat generalists comprised the majority of the butterfly community. Grassland-obligate butterflies comprised only 2% of observations. The dearth of grassland-obligate butterfly species and low native bee abundances suggest that post-CRP fields, especially those grazed by sheep, do not provide abundant and diverse floral resources for native bees and imperiled butterfly species.Item Effects of Grazing of Reed Canarygrass (Phalaris arundinacea) in Restored Wet Meadows in the Northern Tall Grass Prairie(North Dakota State University, 2019) Cleys, Jake RobertReed canarygrass (Phalaris arundinacea) is a grass species that can dominate wet meadow plant communities. This study investigated if grazing by cattle on restored wet meadows suppresses reed canarygrass, thereby promoting the restored plant community. This study was conducted at two locations in northwest Minnesota. Management practices used were a patch-burn grazing treatment and a four-pasture high intensity-short duration grazing rotation. A pretreatment survey was conducted before grazing followed by annual surveys every five years after grazing. Both treatments reduced reed canarygrass canopy cover by 49 percent compared to non-grazed control sites. Grazed patches were moving towards a Carex dominated community. The community not invaded with reed canarygrass had similar native species richness at the end of the experiment in the rotational grazing treatment, and improved plant richness in the patch-burn grazing treatment. This study demonstrates grazing reduces cover of reed canarygrass, while maintaining or increasing native plant species richness.Item Restoring Heterogeneity-Based Management to Rangelands for the Benefit of Grassland Birds and Floral Resources(North Dakota State University, 2021) Duquette, Cameron AlbertWorldwide grassland loss necessitates careful consideration of management practices occurring on those grasslands that remain. Concerns with overgrazing in the early twentieth century led to overcorrection via uniform, moderate stocking. While these practices reversed some forms of rangeland degradation, they also suppressed variability in vegetation structure that is characteristic of native systems. Reduced heterogeneity resulted in biodiversity declines across many trophic levels. In an effort to restore heterogeneity, we reinstated the historic processes of fire and ungulate grazing. We studied the impacts to grassland birds and floral resources, as the Northern Plains are valuable landscapes for breeding grassland birds and both native and managed pollinators. We conducted our research at the Central Grasslands Research Extension Center in Streeter, North Dakota, USA. From 2017-2020, we evaluated grassland bird community composition, nest survival, and floral resource availability. We found that patch-burn and season-long grazing pastures had higher avian diversity than modified twice-over rotational grazing. Avian community composition was also sensitive to ecological site, topographic variability, and wetland area, suggesting that both the fire-grazing interaction and underlying inherent topoedaphic variability maintain biodiversity. Species densities were sensitive to different sources of heterogeneity, with some responding to inherent landscape conditions and some responding to imposed grazing management. We found no differences in nest survival between grazing treatments for any of our 12 focal species despite treatment differences in vegetation and structural components associated with survival. Survival of five species was associated with vegetation structure, and one was associated with litter depth, smooth brome, and forb cover, respectively. We found higher nesting densities of three species (Chestnut-collared longspur, Northern pintail, Brewer’s blackbird) in patch-burn pastures compared to season-long pastures. All are associated with shorter, sparse vegetation. At a treatment scale, we found that patch-burn grazed pastures had shallower litter, less smooth brome, more forbs, and shorter vegetation structure than season-long pastures. Patch-burn grazing pastures increased floral resources across the majority of species. Patch-burn pastures had higher species richness, seasonal availability, and maximum abundance compared to season-long grazing. Our results broadly show the benefits of heterogeneity-based management on two important grassland guilds, birds and flowering plants.