A N tracer technique for assessing fine root production and mortality.

We tested a N tracer technique to assess fine root production and mortality based on temporal measurements of the N mass in fine root structural tissues and the N concentration of the plant-available soil N pool. The results of a pilot study indicated that this technique is based on sound methods and reasonable assumptions. The N tracer technique avoids most of the major limitations which hinder existing methods and may provide valuable insight into the rates and controls of fine root production and mortality in terrestrial ecosystems.