Caragana Establishment, Survival and Regeneration in the Black Hills, South Dakota

Abstract

The purpose of this study was to determine the adaptability and potential wildlife value of Caragana also known as Siberian peashrub for establishment, survival, growth, regeneration, and nutritional qualities. This study was initiated in 1968 in the Black Hills, South Dakota on the McVey Burn (1939), within an open stand of a ponderosa pine forest. Bare rootstock was planted in 1968, and after 35 years survival was 74 percent. Average height was 3 m (10 feet) and plants did regenerate by seed bt did not expand into adjacent habitat. Ideal growing condition evaluated at 35 years, was in a closed tree canopy with 35 percent overstory and basal area 17.7 m2/ha (77 ft2/ acre). Open growing conditions was had exposed areas, canopy cover 17 percent and basal area 5.4 m2/ha (24 ft2/acre). Tree overstory cover on North facing slopes was approximately 2 times greater than on more open south facing slopes. Caragana has not shown signs of spreading from original planting sites. A model developed for habitat assignment defining Closed and Open tree overstory cover for growth, regeneration, and establishment for future sites was 90 percent accurate. Utilization of Caragana by deer based on volume (length x width x height) was 77 percent, 12 years after establishment, with greatest use on south facing slopes. Nutritional qualities of Caragana are generally greater than native shrubs for winter use, with only phosphorous being marginal. The adaptability of Caragana and its qualities makes this browse species suitable for white-tailed deer use for winters. Plantations of Caragana in key wintering areas for white-tailed deer on south facing slopes with Open tree overstory cover and low basal area is recommended for restoration on over browsed ranges.