The Alice Ferguson Foundation/Hard Bargain Farm - Fosters environmental responsibility and enhances the historic legacy and rural character of Hard Bargain Farm by sharing the wonder and excitement of exploring a working farm, woods and wetlands on the Potomac shoreline.

Potomac River Guide - Information and history of the Potomac River.

Chesapeake Bay - regional on-line magazine and information source

Students for Environmental Action - a student run environmental group at the Johns Hopkins University in Baltimore, MD.

Save Our Streams - a non-profit, volunteer based organization that fights to protect and preserve Maryland's 17,000 miles of streams and waterways.

Trash Force - Volunteer group in the Washington, D.C. area that picks up trash and recyclables from public areas every other weekend.

Maryland Cooperative Extension Entomology - integrated pest management, pesticide education and assessment programs, agriculture, green industry, ornamental plants

Maryland Forests Association - a non-profit organization for forest landowners, foresters and other natural resource professionals, hunt clubs and recreational groups, logging and trucking companies, the forest products industry, related businesses and individuals concerned about the wise-use of forest resources.

Maryland Geological Survey - Programs, news, and publications. Includes maps and a discussion of some landscape features.

Wetlands Restoration & Education - comprehensive wetland services, including wetlands design and construction, education, consulting, publications, native wetland nursery plants, applied wetland plant research, and wetlands engineering

The Potomac Conservancy - A land trust dedicated to preserving the scenic and natural Potomac River.

Chesapeake Bay Observing System - Includes water temperature, currents, and salinity.

The Chesapeake Bay Trust - s a non-profit organization that provides financial support grants to civic and community organizations, schools and volunteer groups for Chesapeake Bay restoration and education projects in Maryland.

Chesapeake Bay Program - Chesapeake Bay and its ecosystem. Scientific data, environmental indicators, educational resources, public information, and more.

Montgomery County Sierra Club - Events, issues and newsletter.

Chesapeake Birds of Prey, Inc - specializes in helping injured and orphaned hawks, owls, eagles and other birds of prey.

Washington Suburban Sanitary Commission - Montgomery and Prince George County water/sewer agency, also concerned with the promulgation and enforcement of plumbing and gasfitting regulations in suburban Maryland, and the development and maintenance of storm drainage facilities within its boundaries

Maryland Ornithological Society - promotes the study and enjoyment of birds. Birding activities, publications, and programs are available to members through the state organization or a local chapter.

Maryland Conservation Council - An Environmental Coalition - brings together organizations throughout the state to create a strong voice for the environment and to coordinate effective action by citizens with knowledge, expertise, and energy.

Eyes of Paint Branch - A grass-roots organization of volunteer citizens devoted to preserving the Paint Branch of the Anacostia River through education, community awareness, and action.

Smart Growth in Maryland - initiatives that aim to direct State resources to revitalize older developed areas, preserve some of Maryland's valuable resource and open space lands, and discourage the continuation of sprawling development into our rural areas

Irvine Natural Science Center - A non-profit environmental education organization whose mission is to inspire appreciation and respect for the natural world, and to increase awareness of environmental issues.

Maryland Agriculture on the Web - Definitive site for linking people interested in Maryland agriculture on the web. Includes farms, suppliers, lenders, organizations, educational institutions, and government agencies.

State of Maryland Climatology Office - Offers information about climatology statistics and studies as well as weather conditions and forecasts.