- AlgaeBase Botanical information on terrestrial, marine and freshwater algae
- Angiosperm phylogeny Plant evolution systematics textbook
- BibliOrchidea Most comprehensive orchid literature bibliography
- Biota of North America Program soil, climate and distribution maps
- Botanical Illustration Resources A guide to resources for illustrators, historians, and collectors.
- Bryological Glossary Electronic comprehensive glossary of bryological terminology
- Checklist of Ferns Ferns and fern allies classified taxonomically
- Convention on Biological Diversity United Nations treaty promoting sustainable development
- Dictionary of Natural Products The only comprehensive and fully-edited database on natural products.
- org Floras, checklists, keys, and image galleries for many ongoing floristic projects.
- Flora Brasiliensis Largest flora ever published
- Flora of Brazil Species List Search for information on all known plant species of Brazil
- Fungal Database US National Fungal Collection search names, hosts, literature, specimens
- Global Biodiversity Information Facility Offering publications, meeting notices and data sharing software
- Glossary of Pollen and Spore Terminology Illustrated glossary explaining structures and features
- GrassBase Detailed information about all grass species
- Guide to Green Careers Guide to green carees, trends and degree options
- Guide to Plant Species published in Seed Lists 1800-1900
- Gymnosperm Database Classification, description and ecology of conifers
- How to Name and Register a New Cultivar
- IDB, The Internet Directory for Botany thousands of botanical websites indexed
- Index Fungorum Index of accepted nomenclature for global fungi
- Index Herbariorum Directory of herbaria around the world
- Index Nominum Algarum Taxonomic names of over 200,000 algae
- Index Nominum Genericorum A compilation of the generic names of plants
- Index to American Botanical Literature An index to botanical literature of the Americas published since 1995
- Interactive plant ID keys State by state interactive keys for grasses, legumes, monocots and gymnosperms
- IPNI, International Plant Names Index Standard reference for plant nomenclature
- ITIS, Integrated Taxonomic Information System Authoritative taxonomic information on plants, animals, fungi, and microbes.
- Kew Bibliographic Databases
- Medline US National Library of Medicine life sciences database from 1950 to the present
- Native American Ethnobotany Database Foods, medicines, dyes, drugs and fibers all searchable by tribe
- Neotropical Flowering Plant Identification Extensive list of digital floras, specimen databases and taxon websites
- New York Natural Heritage Program From the NYS Dept of Environmental Conservation
- NGA GEOnet Names Server Standardized names for global topography
- Phytochemical Database From the USDA search for information on thousands of plant chemicals
- Plant List annotated list of all known plant names including bryophytes
- Species 2000 (Indexing the world’s known Species)
- Tree of Life Web Project Collaborative effort to provide biodiversity information
- US Board on Geographic Names Standardized names for US geographic nomenclature
- Web of Science Search over 9,500 journals across the sciences, social sciences and humanities
- World Database of Legumes Over 19,000 taxa described
- A Modern Herbal Over 800 herbs described and prescribed.
- Acta Horticulturae Full text proceedings of ISHS Symposia and International Horticultural Congress
- Algae The US Algal Collection of some 300,000 specimens described.
- American Orchid Society Directories for locating and cultivating orchids.
- American Public Gardens Association (APGA) Search for statistics on all public gardens in America
- Botanic Gardens Conservation International Plant Search Locate rare and threatened plants in cultivation around the world
- Center for Aquatic and Invasive Plants Nearly 500 plants described and photographed.
- Center for Plant Conservation American conservation resource directory and Guide to the National Endangered Collection.
- Checklist of Online Vegetation and Plant Distribution Maps Many interesting historic and contemporary maps.
- Cultivar checklist for ornamental plants
- Culturally Significant Plants Ethnobotanical resource list from USDA
- Find My Roses An online guide to over 31,000 cultivars and their growers.
- Finding Publc Gardens Guide to all US and Canadian public gardens
- Flora of New York State search native plants of New York state by county
- Garden Guides Handy guides for many kinds of garden procedures, designs and plantings
- Go Orchids Find which orchids are endangered near you
- Hardiness Zone Map Check your state’s hardiness zones
- Index of Rainforest related sites Resources on rainforests, sustainable forestry and forest conservation
- International Carnivorous Plant Society Species descriptions, cultivars, and photographs.
- Introduction to Lichens Basic guide to lichenology.
- Introduction to the Fungi Basic introduction to the world of mycology.
- IUCN Redlist of Threatened Species Authoritative listings of threatened and endangered plants.
- National Gardening Association Wide variety of garden related content for consumers and educators
- National Invasive Species Information Center Invasive animal and plant species searchable by geographic location
- Native Plant Finder Locate native plant resources and nurseries near you
- Natural History: atlases, gazetteers, GIS and maps Extensive list of map resources and geographical names
- New York State Urban & Community Forestry Council Resources for tree identification, street trees and urban forestry
- NGA Plant Finder Choose plants from many categories to meet your gardening needs
- Plant Facts Multimedia horticulture center with dictionary, FAQ’s, videos from Ohio State
- Plant Information Online Locate plants from over 1,100 North American nurseries
- Plant Viruses Online Scientific information on all known plant viruses.
- Poisonous Plants Images and information on hundreds of known plant poisons and their effects.
- Pollinator guides Know what you should plant in your area to attract pollinators
- Pronunciation Guide for Latin Plant Names Hear the Latin pronunciation of thousands of plant names
- RHS Plant Selector Over 70,000 plant species described, photographed and indexed
- Seaweed Site Information on the types, uses and classification of marine algae
- Silvics of North America USDA guide to the trees of North America
- Succulent Plant Page Information on collecting, cultivating, and conserving all manner of succulents.
- Tree Encyclopedia Over 450 species of North American trees described and photographed
- Twelve Soil Orders Soil maps of US and soil taxonomy database
- USDA Plants Database Standardized information about the flowering and non-flowering plants of America.
- Virtual Palm Encyclopedia All aspects of palms discussed.
