Herbarium collections shape our understanding of Earth's flora and are crucial for addressing global change issues. Their formation, however, is not free from sociopolitical issues of immediate relevance. Despite increasing efforts addressing issues of representation and colonialism in natural history collections, herbaria have received comparatively less attention. While it has been noted that the majority of plant specimens are housed in the Global North, the extent and magnitude of this disparity have not been quantified. Here we examine the colonial legacy of botanical collections, analysing 85,621,930 specimen records and assessing survey responses from 92 herbarium collections across 39 countries. We find an inverse relationship between where plant diversity exists in nature and where it is housed in herbaria. Such disparities persist across physical and digital realms despite overt colonialism ending over half a century ago. We emphasize the need for acknowledging the colonial history of herbarium collections and implementing a more equitable global paradigm for their collection, curation and use.

Field photographs of plant species are crucial for research and conservation, but the lack of a centralized database makes them difficult to locate. We surveyed 25 online databases of field photographs and found that they harboured only about 53% of the approximately 125,000 vascular plant species of the Americas. These results reflect the urgent need for a centralized database that can both integrate and complete the photographic record of the world's flora.

Extinction rates are expected to increase during the Anthropocene. Current extinction rates of plants and many animals remain unknown. We quantified extinctions among the vascular flora of the continental United States and Canada since European settlement. We compiled data on apparently extinct species by querying plant conservation databases, searching the literature, and vetting the resulting list with botanical experts. Because taxonomic opinion varies widely, we developed an index of taxonomic uncertainty (ITU). The ITU ranges from A to F, with A indicating unanimous taxonomic recognition and F indicating taxonomic recognition by only a single author. The ITU allowed us to rigorously evaluate extinction rates. Our data suggest that 51 species and 14 infraspecific taxa, representing 33 families and 49 genera of vascular plants, have become extinct in our study area since European settlement. Seven of these taxa exist in cultivation but are extinct in the wild. Most extinctions occurred in the west, but this outcome may reflect the timing of botanical exploration relative to settlement. Sixty-four percent of extinct plants were single-site endemics, and many occurred outside recognized biodiversity hotspots. Given the paucity of plant surveys in many areas, particularly prior to European settlement, the actual extinction rate of vascular plants is undoubtedly much higher than indicated here.

It is time to synthesize the knowledge that has been generated through more than 260 years of botanical exploration, taxonomic and, more recently, phylogenetic research throughout the world. The adoption of an updated Global Strategy for Plant Conservation (GSPC) in 2011 provided the essential impetus for the development of the World Flora Online (WFO) project. The project represents an international, coordinated effort by the botanical community to achieve GSPC Target 1, an electronic Flora of all plants. It will be a first-ever unique and authoritative global source of information on the world's plant diversity, compiled, curated, moderated and updated by an expert and specialist-based community (Taxonomic Expert Networks - "TENs" - covering a taxonomic group such as family or order) and actively managed by those who have compiled and contributed the data it includes. Full credit and acknowledgement will be given to the original sources, allowing users to refer back to the primary data. A strength of the project is that it is led and endorsed by a global consortium of more than 40 leading botanical institutions worldwide. A first milestone for producing the World Flora Online is to be accomplished by the end of 2020, but the WFO Consortium is committed to continuing the WFO programme beyond 2020 when it will develop its full impact as the authoritative source of information on the world's plant biodiversity.

Societal Impact StatementAgroecosystems are constantly evolving to meet the needs of a growing population in a sustainable manner. Concerns about ecological impacts of agriculture, including soil loss, have focused attention on crops that provide both agricultural products and ecological services. Perennial, herbaceous crops that live for multiple years and can be harvested mechanically produce large root systems that may reduce soil loss; however, these species are largely absent from agriculture. The diversity of wild, perennial, herbaceous legume species documented by the Perennial Agriculture Project Global Inventory (PAPGI) increases resources available to breeders of perennial, herbaceous legumes, and raises awareness about untapped wild plant diversity in future crop development.Summary Concerns about soil health and stability are focusing attention on crops that deliver both agricultural products and ecological services. Deep rooted, perennial plants that build soil organic matter, support diverse belowground microbial communities, and produce edible seeds are key components underpinning ecological intensification; however, few perennial, herbaceous crops have been domesticated for food. To facilitate development of edible, perennial, herbaceous crops, including perennial grains, we constructed an online resource of wild, perennial, herbaceous species—the Perennial Agriculture Project Global Inventory (PAPGI; http://www.tropicos.org/Project/PAPGI). The first component of this project focuses on wild, perennial, herbaceous Fabaceae species. We extracted taxonomic names and descriptors from the International Legume Database and Information Service. Names were added to PAPGI, a special project within the botanical database TROPICOS, where they link to specimen records and ethnobotanical and toxicological data. PAPGI includes 6,644 perennial, herbaceous Fabaceae species. We built a searchable database, a framework for the ongoing incorporation of more than 60 agriculturally important traits for perennial, herbaceous legumes. Here we highlight food and forage uses for 314 legume species, and toxicological data for 278 species. The novel contribution of PAPGI is its focus on wild, perennial herbaceous species that generally have not entered the domestication process but that hold promise for development as perennial food crops. By extracting botanical information relevant for agriculture we provide a dynamic resource for breeders and plant scientists working to advance ecological intensification of agriculture, and for conservation managers working to preserve wild species of potential agricultural importance.

Lowland savannas, covering an area of 2,342 km2, form the third largest ecosystem in Belize yet are unevenly and therefore poorly represented in the country’s protected area system. Based on more than 5,700 herbarium collections, a checklist of 957 species of vascular plants is presented for this ecosystem representing ca. 28% of the Belizean flora, of which 54 species are new records for the country. Of the 41 species of plants known to be endemic to Belize, 18 have been recorded within the lowland savanna, and nine species are listed in The World Conservation Union (IUCN) 2010 Red List of Threatened Species. Of the total savanna ecosystem flora, 339 species are characteristic of the open savanna, whilst 309 and 114 species are more frequent in forest and wetland areas respectively. Most species (505, 53% of the lowland savanna flora) are herbaceous. Although the lowland savanna has been relatively well collected, there are geographical biases in botanical sampling which have focused historically on the savannas in the centre and the north of the country. A brief review of the collecting history of the lowland savanna is provided, and recommendations are given on how future collecting efforts may best be focused. The lowland savanna is shown to be a significant regional centre of plant diversity.