• Library Catalog (Find Books & Other Materials at Palomar College Library)
• Life Sciences Department
• Palomar Arboretum
• Wayne's Word 

Arboretums

• Arboretum of Los Angeles County

• Kew Web (Royal Botanic Gardens)

• National Tropical Botanical Garden

• New York Botanical Garden

• San Diego Botanic Garden

• U. S. National Arboretum

Databases

• AGRICOLA (USDA National Agricultural Library)
• Carnivorous Plant Database
• Forestry Images (Univ. Georgia)
• Guide to Poisonous Plants
• International Plant Names Index
• National Agricultural Library Digital Repository
• National Register of Big Trees
• Plants Database (USDA)
• Herbaceous Perennial Plants
• Plants for a Future (Rare & Unusual Plants - Edible, Medicinal & Other)

Dictionaries & Glossaries

• Botanical Glossary
• GardenWeb Glossary of Botanical Terms
• PlantFacts (Ohio State University)

Directories

• Agricultural Network Information Center
• CalFlora: Information on California plants for conservation, research, and education
• Ethnobotanical Resource Directory
• Forage Information System
• Internet Directory for Botany
• PlantFacts Search Engine
• Scirus (Elsevier's free web search engine-scientific sources)

Government Information

• National Agricultural Library Digital Repository
• National Agricultural Statistics Service (USDA)
• USDA Economics and Statistics Service
• AGRICOLA (USDA National Agricultural Library)

Museums

• Canada Agriculture Museum
• Natural History Museum, London

Organizations

• American Botanical Council
• American Conifer Society
• American Fern Society
• American Horticultural Society
• American Public Gardens Association
• Botanical Society of America
• California Academy of Sciences Botany Department
• Desert Botanical Garden
• Society for Economic Botany
• U.S. Department of Agriculture

Publications

• Electronic Sites of Leading Botany, Plant Biology, and Science Journals
• JSTOR Biological Sciences Collection (Palomar College only- passwords required off-campus)
• UC Plant Protection Quarterly
• Plants & People (Society for Economic Botany Newsletter)
• Additional print and online journals on botany available from Palomar College.

• The Ancient Bristlecone Pine
• Ascomycota
• Flora of North America
• The Flowering Plant Family
• Flowering Plant Gateway
• Fruit Development
• Horticulture in Virtual Perspective (Ohio State Univ.)
• Invasivespeciesinfo.gov
• Landscape Plants (Oregon State University)
• MendelWeb
• NewCROP: lesser known species of potential economic importance
• Parasitic Plant Connection (Southern Illinois Univ.)
• PlantAnswers (questions &  answers from Texas A&M University)
• Plants for a Future: A resource center for edible and other useful plants
• PlantZAfrica
• Ultimate Tree-Ring Web Pages
• WebGarden: Horticulture and Crop Science
• Wildflowers