N VOLATILIZATION
This is an ongoing work on the use of stable isotopes to evaluate N volatilization and uptake efficiency using a variety of N fertilizer sources and is part of that Jay Raymond PhD research. At the Virginia Piedmont site, the enhanced efficiency fertilizers all reduced volatilization losses with a larger effect following summer application than late winter. Ecosystem recovery after one growing season showed between 13 and 29% of the applied N was taken up by the loblolly pine crop trees and total ecosystem N recovery was greater and the majority of the fertilizer N was in the surface mineral soil and may be available for uptake in subsequent years.