Large-Scale Planting of North Carolina Loblolly Pine in Arkansas and Oklahoma: A Case of Gain Versus Risk

Abstract

Provenance tests in Arkansas and Oklahoma have demonstrated sizeable growth advantage of North Carolina loblolly pine over the local seed source. North Carolina loblolly appears to be well adapted to Arkansas and Oklahoma. Only small differences in cold and drought resistance have been observed so far. The major foreseeable risk is that coastal North Carolina loblolly pine, which evolved on poorly drained and deep soils, will experience greater mortality than the local source under some future extreme drought, especially on excessively drained and shallow soils in the Ouachita Mountains. Weyerhaeuser Company is reducing the risk by planting on soils with relatively low drought risk. Of the 790,000 hectares owned by Weyerhaeuser in Arkansas and Oklahoma 474,000 are deemed appropriate for planting with North Carolina stock.