Wildflowers of the United States

Reference List for Oklahoma Wildflower Identification
Site	Description
Oklahoma Native Plant Society	"In 1987, individuals from throughout the state founded the Oklahoma Native Plant Society to encourage the study, protection, propagation, appreciation, and use of the state's native plants. The society's varied activities (field trips, lectures, workshops, displays, inventories, and roadside plantings) promote an awareness and understanding of some of the state's most valued treasures."
The Wonderful World of Oklahoma Wildflowers by L. George Zabawa	Really nice photos and good information about over 100 Oklahoma wildflowers. Species list, also organized to browse by family and by color. Much more granular color selection than available on most sites (including USWildflowers.com.)
The Noble Foundation Plant Image Gallery	The Samuel Roberts Noble Foundation's plant photographs of a large number of Oklahoma plants. Divided into three sections, the "grasses" and "trees/shrubs" group have the best search capabilities, with the forbs (herbaceous flowering plants) group having the weakest search engine, but they promise that to be improved.
Oklahoma Wildflowers Photo Gallery by Richard Allen	Around 150 Oklahoma wildflowers with nice photographs. All listed on a single thumbnail page with multiple images for some flowers. Larger image page with some additional interesting information available. Alphabetical by common name.
Lady Bird Johnson Wildflower Center at the University of Texas at Austin	Perhaps the most comprehensive native wildflower information site in the United States. "Discover more than 10,050 plants native to North America."
USDA Plants Database	Great resource for native plants! Their own description: "The PLANTS Database provides standardized information about the vascular plants, mosses, liverworts, hornworts, and lichens of the U.S. and its territories." Provides these important (to me) pieces of info: 1) Listing by state and county within a state where specific species have been identified. 2) Scientific name synonyms are listed. 3) Scientific names are matched to a widely-used common name. 4) Photographs of many species. 5) State by state list of all the species identified in that state. Official Citation: USDA, NRCS. 2009. The PLANTS Database (http://plants.usda.gov, 22 June 2009). National Plant Data Center, Baton Rouge, LA 70874-4490 USA.
Flicker Wildflower Field Guide, North America	Over 9,000 Flickr member photos tagged with wfgna. The WFGNA group has good tagging requirements for their excellent photos, so you'll find, in addtion to the photo, the state in which the photo was taken, and at least a common name and the scientific name as identified by the contributor. After you get to the linked page you should add search criteria, including the state name, the color of the plant, or scientific name, to reduce the number of photos. Several states have several hundred photos(California has over 1,500!) so you'll probably want to add color to the search criteria.
WildflowerSearch.com	Steven K. Sullivan has done a tremendous job of putting together a database and search engine to help in identifying wild plants. Not only can you search by plant scientific and common names, you can narrow the results using location (currently lower 48 states and parts of Canada and Mexico), flower shape, color, size, habitat, and observation time. His database currently includes over 7,000 plants. Definitely worth checking out.
Wildflower Information.org	From the site: "WildflowerInformation.org is a resource for wildflower enthusiasts and gardeners. With a growing interest in the environment and natural gardening, our objective is to offer comprehensive information that is easy to use, and accessible for those from the casually interested to the expert." While this information doesn't appear to be on the website itself, WildflowerInformation.org seems to be owned by American Meadows, the "recommended wildflowers seed supplier" of WildflowerInformation.org.
Item at Amazon: National Audubon Society Field Guide to North American Wildflowers--E: Eastern Region - Revised Edition (Commission to USWildflowers.com if purchased)	"...gives full descriptions of more than 650 species found east of the Rocky Mountains, along with notes on several hundred more. The eminently sensible organization relies on first-impression visible characteristics..." I use this guide frequently, and unless I have a good idea what family a flower is in, this is usually still my first stop. In my opinion, a must-have for beginning wildflower enthusiasts; augments more locale-specific wildflower references.

Looking for Wildflowers for a specific state? Check here: Number of References for Oklahoma: 10