Skip to main content
You are here
Facebook icon
Pinterest icon
Twitter icon

Plants to pixels: enhancing access to Kew’s herbarium collections

Anna Saltmarsh
9 May 2014
Blog team: 
As the proportion of Kew’s herbarium specimens accessible online passes a significant milestone, we highlight how researchers and the wider public can explore and interact with these remarkable, and largely hidden, collections.


In late April 2014, the number of specimen records included in Kew’s online Herbarium Catalogue exceeded the 700,000 mark. Half of these records are accompanied by high resolution digital images, all richly informative and often enchantingly beautiful. Although the total number of specimens in Kew’s Herbarium remains uncertain, seven million is a frequently cited estimate. It is therefore now possible to search through 10%, and view 5%, of this world-leading resource from your desktops. While the Herbarium Catalogue provides free and comprehensive access to all of Kew’s unrestricted digital herbarium collections, subsets of these records are also shared via other international resources which repackage the information for the benefit of specific audiences.

Herbcollage Image1.jpg

Photo collage of a selection of specimen sheets from Kew’s herbarium collections.
A selection of specimen sheets from Kew’s Herbarium collections.


In association with other European Union natural history heritage institutions, Kew participated in a project known as OpenUp!. Involvement in OpenUp! has enabled Kew to share our herbarium specimen images alongside multi-media content provided by a broad mix of heritage collections via an online resource called EuropeanaEuropeana is a multi-lingual digital library of cultural and scientific heritage items providing access to over 30 million objects from more than 2,300 institutions, ranging from the British Library to the Norsk Folkemuseum in Oslo or the Museo Galileo in Florence.

The most recent release of OpenUp! content in Europeana presents over 315,000 of Kew’s herbarium specimen images, and also now includes over 1,800 images of items from Kew’s Economic Botany collection. What is more, the scientific plant names tied to each of these specimens are linked to a multi-lingual database of vernacular names. Now, for the first time, it is possible to conduct an exploratory search of Kew’s herbarium and economic botany specimens using a common name such as poppy, edelweiss or rubber. If you try this with your own examples you are sure to uncover something unexpected.

This increased discoverability promises to transform everything from school student projects to the way professional research is conducted, particularly in the humanities, but also amongst scientists and historians of science.


Photo of a set of rubber dentures from Kew’s Economic Botany collection alongside a specimen of the rubber plant, Hevea brasiliensis, collected by Richard Spruce in 1849.
A set of rubber dentures from Kew’s Economic Botany collection alongside a specimen of the rubber plant, Hevea brasiliensis, collected by Richard Spruce in 1849.

Global Biodiversity Information Facility (GBIF)

Sharing Kew’s herbarium specimen images in Europeana is an exciting step which we anticipate will broaden the audience and use of these collections, but their fundamental purpose has always been to support scientific research. For this reason, Kew’s specimen information is shared via data portals targeted at an international scientific audience. The Global Biodiversity Information Facility (GBIF) was established in 2001 with the intention of making biodiversity data ‘freely and universally available for science, society and a sustainable future’. GBIF’s data portal was officially launched in 2007 and Kew specimen records have been accessible there since then.

The GBIF portal has itself undergone recent changes, with the 2013 relaunch introducing a simplified user interface. GBIF provides access to over 400 million records of specimens and observations across the living world. Data from this source have been used to support publications in key areas of research such as the impacts of climate change, management and monitoring of invasive species and conservation of wild species and crop diversity.

The Global Plants Initiative (GPI)

For the taxonomist audience, the most significant objects within Kew’s herbarium collections are the ‘type specimens’. These are original materials upon which new species or other taxon descriptions have been based and to which scientific names are permanently fixed. Plant type specimens have been the subject of a concerted international digitisation effort over the past decade, through a series of projects generously supported by the Andrew W. Mellon Foundation and known collectively as the Global Plants Initiative (GPI). GPI brings together over 300 participating herbaria from 75 countries. Their digital outputs are combined in a scholarly resource called JSTOR Global Plants, which has recently published over 2 million type specimen images. These images follow a standard of excellence for quality and resolution (600ppi) which enables experts to distinguish closely related species through examination of fine morphological characters. 

Digitisation of all known type specimens in Kew’s collections is due for completion within the next 12 months. JSTOR Global Plants incorporates other botanical resources such as digitised Floras and archive materials, including Kew’s Directors’ Correspondence collection. 

DCU team members 2014 Image 3.jpg

Photo of Members of the Herbarium Digital Collections Unit in April 2014.
Members of the Herbarium Digital Collections Unit in April 2014 represent just a few of the many individuals who have contributed to the extensive digitisation effort.


Further extension of Kew’s digital content has been made possible via collaboration with Brazilian partners with financial support from Natura and FAPEMIG. Over the past two years, in the context of the Reflora project, over 70,000 Brazilian specimens have been newly imaged at Kew and shared with partners at the Rio de Janeiro Botanical Garden where label data is being transcribed. In total, images of almost 95,000 of Kew’s estimated 300,000 Brazilian sheets have now been shared, contributing to the Reflora Virtual Herbarium which aims to include the majority of Brazilian herbarium specimens held in-country and in significant international herbaria.

Harnessing the power of the crowd

One way in which Kew is seeking to enhance the pace of data-sharing, is to provide opportunities for volunteers to help capture data from the still-hidden components of our collections. With support from Defra, Kew’s Digital Collections team has been testing new workflows for specimen imaging, with a view to distributing the important step of data transcription from labels. For readers who wish to try their hand at this, a set of Kew’s British specimen collections are available for transcription on the Herbaria United website, developed and managed by the Botanical Society of Britain and Ireland (BSBI).

K000811691 man orchid.jpg

Image of a specimen of the man orchid, Aceras anthropophorum
A specimen of the man orchid, Orchis anthropophora (Aceras anthropophorum), transcribed with the help of volunteers via the Herbaria United website.

A great deal has been achieved in terms of expanding and enhancing the accessibility of Kew’s Herbarium and associated collections throughout the past decade, gathering pace in recent months. There is little doubt that the next ten years will see further advances in this area, bringing more of Kew’s collections into our homes and workplaces, enabling participation and use in ways we have yet to imagine. 

- Anna -

Browse by blog team