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 (
LockA locked padlock
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Image Number K6064-8
Agronomist Rufus Chaney examines the roots of a metal-accumulating Thlaspi plant in a growth chamber.
Photo by Keith Weller.
640 pixels wide: (k6064-8.jpg)