Restoration Ecology: Free Online Databases & Search Engines

PubAg is a portal to USDA-authored and other highly relevant agricultural research. It delivers over 40,000 full-text journal articles by USDA staff and includes nearly 450,000 citations.

National Agricultural Library's database of journal articles, books & book chapters, technical reports, extension bulletins in all areas of agriculture. Coverage from 1979-present.

Online system for locating and accessing over 24,000 publications by US Forest Service scientists. Publications include research monographs published by the agency as well as papers written by USFS scientists but published in journals, conference proceedings, or books unaffiliated with the USFS.

Online directory that indexes and provides access to high quality, open access, peer-reviewed journals.

A searchable online database of more than 3 million federal publications.

Over 100,000 full text publications from the U.S. Geological Survey and the U.S. Department of the Interior.

OSTI.gov is a portal to free, publicly available DOE research and development (R&D) results.

Index to Environmental Protection Agency (EPA) publications. Includes full text links.

"Science.gov searches over 60 databases and over 2200 selected websites from 15 federal agencies, offering 200 million pages of authoritative U.S. government science information including research and development results."

"ScienceResearch.com is a free, publicly available deep web search engine that uses advanced "federated search technology" to return high quality results by submitting your search query - in real-time - to other well respected search engines then collating, ranking and dropping duplicates of the results."

"A global science gateway connecting you to national and international scientific databases and portals." Provides documents and citations from scientific repositories around the world.