2007 Annual Report 1a.Objectives (from AD-416) The objective of this cooperative research project is to identify alternative sources to pinebark as a container substrate for widespread use in the nursery industry. In recent years there has been an increasing demand for pinebark as an energy source coupled with a steady decline in domestic timber production due to foreign imports. This along with the rapid growth in the horticulture and landscape industry has resulted in reduced market share of pinebark for horticultural use. 1b.Approach (from AD-416) Research conducted will evaluate alternative substrate sources for their potential to have widespread use as a container substrate for nursery production. Criteria for selection will include: cost effective while producing comparable plant growth, widely available, non-toxic to nursery crops, stability in production process, and appropriate physical and chemical properties. Possible sources are agricultural, industrial and municipal waste as well as agronomic crops which might provide a sustainable biomass source as opposed to a byproduct of another industry. 3.Progress Report This report serves to document research conducted under a Specific Cooperative Agreement between ARS and Auburn University. Additional details of research can be found in the report for the in-house project 6404-21220-003-00D, "Vegetable and Ornamental Research in the Gulf South." Studies have been completed evaluating nitrogen use in perennial crops with ‘Clean Chip Residual’ (CCR) and ‘WholeTree’ substrates. Results were presented at the Southern Region of ASHS and other results will be presented at the Southern Nursery Association Research Conference in August 2007. Studies are under way evaluating nitrogen immobilization in CCR substrate. The ADODR meets regularly at least monthly with the cooperating scientist and these meetings include site visits.