Directories and Databases
Botanical Library Listing of Herbaria Worldwide
Botanical Databases at the Smithsonian Institution
Aquatic and Wetland Plant Database
PLANTS National Database(USDA)
Medical and Poisonous Plants Database
Medical and Poisonous Plants Database2
Canadian Poisonous Plants Information System
Poisonous Plant Databases
TROPICOS (Worldwide Nomenclature Database)
Phytochemical and Ethnobotanical Databases
Plant Chromosome Numbers Database
Plant Taxonomists Online
Authors of Plant Names
Plants for the Future   -A Resource and Information Centre for Edible and other useful plants    

Systematics
DELTA (Descriptive Language for Taxonomy)
Flora of North America
Families of Flowering Plants
Family Names in Current Use
Plant Taxonomists Online
Authors of Plant Names

Poisonous Plants
Cornell University Poisonous Plants Webpage
Medical and Poisonous Plants Database
Medical and Poisonous Plants Database2
Canadian Poisonous Plants Information System
Poisonous Plant Databases

Botany Links
Tropical Plant Database
Wildflower Links
Internet Directory for Botany: Vascular Plant Families
Internet Directory for Botany: Checklists, Floras, Taxonomic Databases, Vegetation
Internet Directory for Botany: Software
Smithsonian Institution Botany Department
Botany.com Encyclopedia of Plants

Local Floras
Checklist of the Vascular Plants of Wisconsin
Checklist of the Vascular Plants of Texas
Generic Flora of the Southeastern United States Project

Government
US Forest Service Home Page
Chequamegon-Nicolet National Forest Home Page
USGS-NPS Vegetation Mapping Program products by state
Antioch Dunes Nat. Wildlife Refuge, A Second Nature Study
EROS home page
Food and Drug Administration Home Page
Natural Resources Conservation Service: Plants Project

Organizations
California Native Plant Society
Ecological Society of America Home page
Botanical Society of America
Audubon Online -- National Audubon Society
Home Page of The Nature Conservancy - Help Protect Endangered Species
North Country Trail Association Home Page
American Forest and Paper Association
Native Plant Society of Texas
American Society of Plant Taxonomists
International Association for Plant Taxonomy
International Organization for Plant Information
Native Plant Conservation Initiative
The Nature Conservancy
Organization for Tropical Studies (OTS)

Ecology and Biodiversity
Tree of Life  -A distributed Internet project containing information about phylogeny and biodiversity.
Biodiversity Worldmap
Flora2K-Biodiversity on the Internet
SpORE - Spatially Oriented Research in Ecology
Forestry & Forest Ecology Lab (School of Resource and Environmental Management) Home Page

Miscellaneous
What Are All Those Dead Plants For, Anyway?  -Questions and answers about herbaria
Plant Trivia Timeline  -The Timeline gives world history from the viewpoint of a botanist.
The Statistics Home page
TerraServer Home page
Climate Change Tree Atlas of Eastern USA
AltaVista Translation Service
Geographic Names Information System
MLA (Modern Language Association)
MLA  -a guide from the Columbia Univeristy Press