The Effects of Herbivory and Vegetation Competition on Seedling Survival and Growth in the Middle Sheyenne River Watershed, North Dakota

Abstract

There is a concern about the lack of regeneration of riparian hardwood forest communities in the Middle Sheyenne River Watershed of northeastern North Dakota. Natural resource managers and landowners are unsure if herbivory by ungulates or other factors are responsible for a lack of tree seedling regeneration and survival. We focused our research on the role of ungulates and competitive vegetation in seedling survival and growth in demonstration tree planting sites. Landowners utilized exclosures from ungulate browsing and/or grazing, and different forms of vegetation control. The riparian study showed the combination of deer with cattle significantly affected survival of seedlings after three years at p<0.012, and that vegetation competition played less of a role in seedling survival. The upland study found that tree and shrub species in general did not respond significantly in terms of overall growth with treatments such as fabric and glyphosate herbicide to control vegetation competition.