bioRxiv (pronounced "bio-archive") is a free online archive and distribution service for unpublished preprints in the life sciences. It is operated by Cold Spring Harbor Laboratory, a not-for-profit research and educational institution. By posting preprints on bioRxiv, authors are able to make their findings immediately available to the scientific community and receive feedback on draft manuscripts before they are submitted to journals.

Global Invasive Species Database (GISD) aims to increase awareness about invasive alien species and to facilitate effective prevention and management activities. It is managed by the Invasive Species Specialist Group (ISSG) of the Species Survival Commission of IUCN (the International Union for Conservation of Nature).

The Medicinal or therapeutic uses of the plants described in this guide are not to be construed in any way as a recommendation by the authors or the U.S. Department of Agriculture. Some of the dried crude drugs, which must be modified considerably before commercial use, can be extremely poisonous when not used properly. Readers are cautioned against using these plant drugs for purposes of self-medication. Besides descriptions of 126 medicinal plants of the Appalachian region, this guide includes a glossary of the terms used a reference list of publications, and a listing of additional source material.

The web's premier source of information on conifers and their allies. Since we went online on 1997, the Database has attracted worldwide attention as a readily accessible, scientifically accurate source of information on the classification, description, ecology and uses of this culturally and ecologically important group of plants. This home page gives some hints about how to navigate the Database, as well as providing background information for the curious.

Coverage includes foods, drugs, dyes, fibers and other uses of 4,029 species of plants by 291 Native American groups. Each entry includes Latin and common name, Native American group, uses and source of information. Searchable by keyword. Boolean search available.

The New York Flora Atlas (Atlas) is an online resource for information including distribution of all the vascular plants that occur in New York State. Information is also available for taxa which have been erroneously reported from New York (excluded taxa). In addition to distribution, the atlas provides information for each taxon about habitat, taxonomy, native/non-native status, synonymy, and more. Images are also being added. Accepted taxa and their distributions are based on vouchered specimens housed at public herbaria.

The Noble Research Institute Plant Image Gallery is designed to assist botanists, ecologists, natural resource managers, educators and hobbyist with the identification of plants commonly found in the southern Great Plains.

North American Plant Atlas (NAPA) is an online database of maps of most of the native and naturalized species of plants growing in North America.

Searchable database of over 260,000 pages of extension service factsheets from forty-six universities and government agencies. Search can be limited by region.

ArbPIX (the Arnold Arboretum plant image database) is a free resource of historical and contemporary images of accessioned plants. Images detail structural characteristics (morphology) and seasonal aspects (phenology) of temperate woody plants in the living collections. These images are shared and used for educational purposes in classrooms, garden clubs, and homes around the world. They are available for non-commercial use under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) license.

Includes searchable database of plant images, distribution information and plant classification information including hierarchical listing. Plant checklists are searchable by state. Plant characteristics section includes information on physiology, growth requirements, reproduction and suitability/use.

Includes entries for over 7,000 useful plants. Coverage includes physical characteristics, habitats, edible, medicinal and other uses, cultivation and propagation information, scent, select cultivars, print references and web reference links. Searchable by Latin and common name, use, area or habitat.

Plants of the World Online (POWO) which is an international collaborative programme that has as a primary aim to make available digitized data of the world’s flora gathered from the past 250 years of botanical exploration and research. POWO also aims to make freely available electronic data created by different projects but that no longer have an online presence or where data was never made available externally. It delivers information on the taxonomy, identification, images, distribution, traits, threat status, molecular phylogenies and uses of vascular plants worldwide.

The Purdue University Aromatic & Medicinal Plants Index is an online database dedicated to medicinal and aromatic plants.