Atlas of Florida Vascular Plants: http://florida.plantatlas.usf.edu/
The Atlas of Florida Vascular Plants is a joint effort by the Institute for Systematic Botany, the University of South Florida and the Florida Center for Community Design & Research to provide users with a comprehensive searchable database of vascular plants in the State of Florida.
Wildland Weeds: http://www.fleppc.org/wildlandweeds/
Wildland Weeds magazine is the official publication of the Florida and Southeast Exotic Pest Plant Councils and all affiliated chapters. The purpose of the magazine is to provide a forum for communication for all those interested in invasive plant issues in the southeastern U.S.
USDA plants: http://plants.usda.gov/java/
The PLANTS Database provides standardized information about the vascular plants, mosses, liverworts, hornworts, and lichens of the U.S. and its territories.
Center for Aquatic and Invasive Plants: http://plants.ifas.ufl.edu/
The UF/IFAS Center for Aquatic and Invasive Plants is a multidisciplinary research, teaching and extension unit directed to develop environmentally sound techniques for the management of aquatic and natural area weed species and to coordinate aquatic plant research activities within the State of Florida.