An essential website is the USDA Natural Resources Conservation Service Plants Database. This huge database includes a search function utilizing a common name or scientific name, photos and illustrations, geographic distribution maps, and links to other resources with even more information about a specific plant.
Although designated as a “weed identification guide” specifically for the southeastern U.S., this website by Virginia Tech includes detailed information with excellent supporting photos. The guide carefully notes similar looking plants and provides a link to the similar plant’s description. The “weeds” found in the southeastern U.S. can also be found in other parts of the U.S. and the world (e.g., dandelion, white clover, St. Johnswort, plantain).
The Lady Bird Johnson Wildflower Center, located at the University of Texas at Austin, has a wonderful Native Plant Database. By selecting some typical plant characteristics, you can obtain helpful search results — which reduces the number of plants to consider as you identify an unknown plant.
Southeasternflora.com utilizes a simple online key to identify plants in the southeastern portion of the U.S. Key characteristics include flower color, plant form, leaf type and leaf arrangement. You can also search on a plant’s common or scientific (species or family) name. Each featured plant includes numerous excellent photos along with basic information.
Missouriplants.com is an excellent resource when searching by the scientific name of a plant. The site includes detailed photographs with notes on stems, leaves, flowers, inflorescence, habitat, etc. — with an emphasis on plants found in Missouri (although the plant photos were taken throughout the U.S.).
The USDA Natural Resources Conservation Service “National Plant Data Center” includes interactive keys (polyclave key) and plant character data sets for some groups of plants. The data is available for grasses (Poaceae family) and legumes (Fabaceae family) — among other plant families — for each state in the U.S.
This polyclave key helps identify a plant’s “World Wide Flowering Plant Family.”
For an extensive list of Internet resources, visit the Vocational Information Center – Horticulture Basics and Plant Identification. I continue to review this list and will gradually highlight some of my favorites here. The description on this web page notes that the learning resources link to: “classification of plants, plant glossaries, plant cell basics, plant propagation, photosynthesis, biomes, habitats, hardiness zones, plant identification, plant images, endangered plants, and history of horticulture.” The links and information are global.
Dave’s Garden claims to be “the largest plant database in the world” and focuses on plants favored by gardeners. It’s a great resource for photos to confirm a plant’s identification.
MountainNature.com features plants growing in the Canadian Rockies.
Southwest Colorado Wildflowers focusses on wildflowers, ferns and trees in the Four Corners area (Colorado, New Mexico, Arizona and Utah). At this well-designed website, you can learn basic plant identification skills, pick up great tips for taking photographs of plants, and identify plants.
The Field Guide to Noxious and Other Selected Weeds of British Columbia includes excellent plant photos and descriptions for weeds in British Columbia.
The Virtual Herbarium utilizes an interactive key to identify the family for a plant. Two sets of data are included on the site: (1) 248 species of trees in Miami, Florida and (2) flowering plants of Jamaica. In addition, there are links to other interactive keys available on the internet.