WOOSTER, OHLoblolly pine bark is the primary component of nursery container substrates in the eastern United States, but a shortage of the widely used organic material is prompting researchers to investigate new materials as potential alternatives. A recent study by James E. Altland and Charles Krause of the USDA Agricultural Research Service at the Ohio Agricultural Research and Development Center was designed to determine if ground switchgrass can be used as an alternative substrate for short production-cycle woody crops.
Altland and Krause conducted two experiments with 'Paprika' rose (Rosa L. 'ChewMayTime') potted in 15-centimeter containers. The experiments revealed that switchgrass processed to an appropriate particle size and amended with typical nursery materials can provide a suitable substrate for short-production-cycle woody crops.
Containerized nursery and greenhouse crops are grown almost exclusively in soilless substrates. Substrates for outdoor nursery crops are primarily composed of softwood bark amended with peatmoss, sand, pumice, perlite, compost, and/or other materials. Softwood barks used by the nursery industry are regional and highly dependent on local inventories; most nurseries on the East Coast, Midwest, and in the southern United States use loblolly pine bark, while nurseries on the West Coast use douglas fir bark. A decrease in forest products output, coupled with increased use of bark as a fuel at paper and lumber mills, has caused a decline in the amount of pine bark available for horticultural use. Increasing demand for wood-based ethanol over the next 20 years will cause even greater competition for pine bark and other woody biomasses.
"Research on the use of pine wood materials as alternatives to pine bark is proving successful in the southeastern United States, where pine plantations, paper mills, and lumber mills are abundant", stated Altland. He explained that widespread use of these materials
|Contact: Michael W. Neff|
American Society for Horticultural Science