Botanical Gardens and Arboretums

American Public Gardens Association -
Botanic Gardens Conservation International (U.K.) -
Botanical Research Institute of texas -
The Garden Club of America -
Missouri Botanical Garden -
National Tripical Botanical garden -
New York Botanical Garden -

Horticulture and Gardening Links 

American Horticultural Society -
American Society of Horticultural Science -
Gardening Know How -
GardenWeb -
International Society for Horticultural Science -

Botany Links 
Asociación Latinoamericana de Botánica, ALB (Latin American Society of Botanists)
Bishop Museum Botany Page
Botanical Society of America -
Botany online -
California Plant Names: Latin and Greek Meanings and Derivations
Field Museum of Natural History - Botany
Hunt Institute for Botanical Documentation -
Index Herbariorum ( Index Herbariorum) -
International Aroid Society -
International Organization for Plant Information -
International Plant Names Index (IPNI) -
Internet Directory for Botany -
National Biological Information Infrastructure (nbii) - Botany -
National Plant Germplasm System -
Natural History Museum (London) Botany Collections -

Biology and Other Science Links 
Endangered Species Program U.S. Fish and Wildlife Service -
National Academy of Sciences -
National Genetic Resources Program: GRIN -
National Museum of Natural History (Smithsonian Institution) -
National Science Foundation -
The Natural History Museum (London) -
U.S. Fish and Wildlife Service -

Conservation and Ecology Links 
East African Wild Life Society
Ecological Modelling -
Ecological Society of America -
Ecology and Society -
The Eden Project -
Fauna and Flora International -
Forest Protection Portal -
Gap Analysis Program, striving to keep common species common
Global Change Master Directory, NASA -
Hawaii's Most Invasive Horticultural Plants -
International Society for Ethnobiology -
The Man and the Biosphere (MAB) Programme -
National Council for the Environment -
The Nature Conservancy -
Nature Kenya and the East African Natural History Society -
Society for Conservation Biology -
Society for Ecological Restoration -
Society for Economic Botany -
U.S. Global Change Research Program -
U.S. Long-Term Ecological Research Network (LTER)
World Conservation Monitoring Centre, UNEP -

Forestry and Dendrology Links 

Forest Conservation Links -
Global Forest Watch - 
World Agroforestry Center -

Phylogeny, Taxonomy and Biodiversity 
American Society of Plant Taxonomists -
Association for Biodiversity Information - Southwest -
ETI BioInformatics World Taxonomists Database -
GBIF - Global Biodiversity Information Facility -
KBD: Kew Bibliographic Databases -
Natural Science Collections Alliance -