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Factors influencing establishment of eastern red cedar (Juniperus virginiana L.) on rangeland
Abstract
Eastern redcedar (Juniperus virginiana L.) has increased in size, acreage, and locations. It has been the most rapidly expanding tree resource in the Great Plains. Reasons for the presence or absence of eastern redcedar and management solutions have not been determined. Objectives were: to determine the effect of year of establishment, grazing impacts, and aspect on the emergence of seed and on the survival of seedlings of eastern redcedar; and to determine the age of existing eastern redcedar stands at eight sites across Nebraska. Sampling units of 100 seed and 10 seedlings were replicated at two locations in central Nebraska. Plots were established on three different grazing levels (actively grazed, fenced from grazing, and not grazed in the last 50 years) with split-plots established on three different aspects (north-facing, south-facing, and flat). Sampling units were planted in 1987 and 1988 as split-split plots. Seed germination and seedling survival were evaluated after 6, 18, and 30 months. Eastern redcedar seed did not emerge in the field. Year of establishment influenced seedling survival after 18 months. Grazing effects and aspects were significant factors in the survival of eastern redcedar seedlings of all three evaluation periods. Highest survivals due to grazing impacts on vegetation and soil properties occurred on fenced from grazing areas. Areas not grazed had the lowest survival of eastern redcedar seedlings. Highest survival for aspects occurred on north-facing slopes with lowest survivals on south-facing slopes. A total of 420 trees from eight sites were aged. The majority of the trees established during the 1950's. Uneven-aged stands of eastern redcedar occurred on the sites investigated. Trees established in almost every year until the site became fully occupied. There was a consistent increase in total tree numbers within ten to 15 years after initial establishment on every site. Land managers can impact eastern redcedar seedling establishment through different grazing treatments. Grazing impacts are of greater importance in years of above average precipitation and on north-facing slopes.
Subject Area
Range management|Forestry|Agronomy
Recommended Citation
Schmidt, Thomas Leslie, "Factors influencing establishment of eastern red cedar (Juniperus virginiana L.) on rangeland" (1991). ETD collection for University of Nebraska-Lincoln. AAI9129571.
https://digitalcommons.unl.edu/dissertations/AAI9129571