Red oak seedling response to different topsoil substitutes after five years

Abstract

Northern red oak is a valuable commercial species occurring throughout the Appalachian Coalfields Region. It reportedly grows on mined land, but little is known about preferred site and soil conditions for this species on mined land. The purpose of our field study was to test red oak survival and growth rates on a variety of topsoil substitutes. The study is located in Wise Co., Virginia on the Marcum Hollow member of the Upper Wise Formation. The site was mined in 1979 and reclaimed in 1980. In 1981, field plots were constructed with different topsoil substitutes spoil mixes and pitch x loblolly pines were planted in 1983. In 2001 the pines were removed and replaced with red oaks in the winter of 2001-2002. Four replicate plots of five different mine spoil mixes were planted with nine red oak seedlings each. Mine spoils consisted of different proportions of weathered sandstone and un-weathered siltstone. Tree survival, height and diameter were measured each year for five years. Results show that survival and growth was best on topsoil substitutes consisting of a mix of sandstone and siltstone. Trees survived and grew poorly on plots constructed from either pure sandstone or siltstone. Reasons for the poor oak performance on the high sandstone plots were not clear, but could possibly be related to lower pH and available Ca levels. Poor oak performance on the pure siltstone plots was most likely related to higher rock fragment and lower bulk water holding content.