Usage:
| Adirondack Council Inc |
| American Civil Liberties Union |
| American Forests |
| American Indian College Fund |
| Arbor Day Foundation |
| Atlanta Botanical Garden |
| Barnes Foundation, The |
| Bay Journal |
| Big River Magazine |
| Burgess Seed & Plant Co |
| California State Parks Foundation |
| Central Park Conservancy |
| Chesapeake Bay Trust |
| Consumer Reports |
| Cornell Lab Of Ornithology |
| Cousteau Society |
| Defenders of Wildlife |
| Denver Museum of Nature & Science |
| Ducks Unlimited |
| Earthjustice |
| Elkhorn Slough Foundation |
| Environmental Defense Fund |
| Food & Water Watch |
| Food Banks Consortium |
| Franklin Institute, The |
| Fred Hutchinson Cancer Rs |
| Friends of the Earth |
| Friends of the Forest Preserves |
| Grand Canyon Conservancy |
| Greater Public |
| Green Chimneys |
| Greenbelt Land Trust |
| Greenpeace |
| High Country News |
| High Museum Of Art |
| Holden Forests & Gardens |
| Humane Society Consortium |
| International Crane Foundation |
| Jane Goodall Institute, The |
| KBTC Public Television |
| Keepers of the Wild |
| KQED, Inc. |
| Lions, Tigers and Bears |
| Los Angeles Mission |
| Massachusetts Audubon Society |
| Meals on Wheels Co-Op |
| Minnesota Conservation Volunteer |
| Mono Lake Committee |
| MSPCA |
| National Geographic Development |
| National Park Foundation |
| National Parks Conservation Assoc |
| National Trust/Historic Preservtn |
| Natural History Museum/LA County |
| Natural Resources Defense Council |
| New Jersey Audubon |
| New York Restoration Project |
| North Texas Food Bank |
| NY Landmarks Conservancy, The |
| Ocean Conservancy, The |
| Ohio Environmental Council |
| Oklahoma Today |
| Parks & Trails Council of MN |
| Parks & Trails New York |
| PBS SoCal - KOCE-TV Foundation |
| PBS Wisconsin |
| Pennsylvania Horticultural Soc |
| PETA Foundation |
| Prospect Park Alliance |
| Public Radio/Television |
| Public Television |
| Rensselaer Plateau Alliance |
| Rescue Missions |
| Sierra Club |
| Smile Train |
| Smithsonian Magazine |
| Southern Utah Wilderness Alliance |
| SPCA of Texas |
| Trustees of Reservations |
| UNC Public TV |
| WFMT Chicago Public Radio |
| WHYY |
| Woods Hole Oceanographic |
| Yellowstone Forever |
| Zoo Consortium |
