No, I haven't left the caps lock key on.
NBII LIFE is the National Biological Information Infrastructure (NBII) Library of Images from the Environment (LIFE), a collaborative effort to make diverse, high-quality images (photographs, illustrations, and graphics) of the environment freely available for research and other nonprofit uses. This is an outreach effort by the Smithsonian Institution who have a more extensive plants database at http://botany.si.edu/PlantImages.
Another (sometimes parallel) source of images is the USDA's PLANTS database. Whereas LIFE includes everything in categories of animals through weather, PLANTS focuses on plants, of course.