An official website of the United States government
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
 Image Number D1972-3 |
ARS technician Dianne Snuffer extracts tannins from samples of rainwater collected after it ran down trees. She is using the solid phase extraction technique to investigate the effects of tannins on soil organic matter, nutrient cycling, and water quality.
Photo by Stephen Ausmus.
