Editor’s Note: This is the ninth post to the Digital Natural History series edited by Nick Koenig and Heather Rogers.

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In the 21^st century, there has been a burgeoning interest in natural history collections as sources of information about Earth’s biodiversity and how much of it is being threatened and lost.  More than three billion specimens are stored worldwide and in order to make these specimens better known, there are significant, ongoing efforts to digitize the specimen’s label data and in many cases also photograph them as well.¹ This is particularly true for herbaria which house collections of preserved plant specimens.  Since many of these pressed plants are attached to paper, they are relatively easy to scan or photograph. The images and data can then be uploaded into large databases including GBIF (the Global Biodiversity Information Facility), which aggregates data from many sources including Canadensys, a project to make the biodiversity data held in Canadian biological collections available to researchers around the world (Figure 1). 

Until the 18th century, many specimen sheets were bound into volumes so they could be stored much as other books were. This method of preservation meant the specimens couldn’t easily be resorted if, for example, a collector wanted to put similar species together. Many of the oldest herbarium specimens are bound, protecting the sheets from wear-and-tear and ensuring their survival. In Oak Spring Garden Library in Virginia, there is a volume dating from 1595—about a half century after the first herbaria were created.  It was made by Johannes Harder (c.1563-1606), a German physician and son of Hieronymus Harder, who also produced herbaria, some of which are still extant in European collections.  Most of the plants in these herbaria were from southwestern Germany, close to where the Harders lived. What makes these collections particularly interesting is that the Harders adopted a technique rarely used by other botanists:  they painted in missing plant parts with watercolor.  Johannes was much more liberal in this regard, with almost every specimen embellished. His unusual approach is one that drew me to his plant collections.

Here, I argue that the Harder herbarium has a special place in the history of botany, one of only a few examples of a hybrid with both specimen and painting. The age of the collections’ paper and plants means that it has to be handled with the same care afforded other manuscripts from this time. Produced in the early modern era, this herbarium can be studied not only scientifically, but from the viewpoint of codicology much as a medieval manuscript would. Harder’s herbarium documents botanical practice in the early modern era. For example, while it originally had plant names given in Latin and German, Polish names for many plants were added later, suggesting a change in ownership. The wear on its pages and binding indicate that it was well-used, perhaps as a guide to medicinal plants in teaching medical students or as a reference for an apothecary. The plants are mounted on both sides of each sheet of paper, often with more than one species per page. Neither of these practices are found in present-day collections.

Harder’s herbarium dates to a time when Western botanical science was developing, when its vocabulary was still immature, and even such fundamental terms as species and genus were still a century away from being clarified. Botanists were collecting both plant specimens and images to harvest as much information about a species as possible and artists were experimenting with the best ways of representing plant structures accurately and clearly.² In his herbarium, the Swiss botanist Felix Platter often affixed a drawing or illustration on the left-hand page opposite a specimen of the same species on the right so he had both accessible at the same time.³ Others added nature prints to specimens as a way to supplement the available information about the plant. Like Harder’s use of painted additions, however, most of these approaches did not become standard in botanical practice, although drawings are still sometimes added to specimen sheets.

Within Harder’s collections, common additions to the specimens were roots and bulbs, two elements often omitted from collection and preservation because they were bulky or took up too much space (Figure 2). Harder instead tamed them in paint. If neither were drawn, he usually painted a grassy tuft from which the stem appeared to grow. This was “generic,” not indicative of a particular habitat. A few specimens included elements of background, even environmental clues, beyond the tufts: a rock behind a fern, a tree trunk background for a lichen, a wooden dowel supporting the stem of a morning glory, a carnation in a flower pot, and a marsh plant with its roots sitting in blue water. In some cases, missing portions of stems or leaves were added or missing petals from a flower. In a few instances the additions were more significant than the specimen itself, such as an arum where the entire flower stalk was painted with a leaf pasted on either side of it (Figure 3).

In the manuscript tradition, there is a title page followed by indices for both Latin and German plant names; these are ruled in red ink, while the rest of the pages are ruled with pencil lines on the left and right sides. The paper is watermarked, identifying a maker active in the same area at that time. Like any approach using a bound manuscript, digitization involved much more care than would be used for modern specimens. The volume had to be treated more as a medieval bible would be, correcting for curvature and warping of the pages.

But since the materiality of Harder’s manuscript includes specimens, it could also be studied with some of the latest scientific techniques. For example, there are specimens of Latin American species such as tomato, tobacco, pepper that are included in the manuscript, and small samples could be taken and used in DNA sequencing. This has already been done successfully with a tomato plant from a mid-16^th century herbarium.⁴ There are several other tomato specimens from this time that could be tested in the future. This process could yield information on how closely the specimens found in different collections are related to each other genetically.  Similar testing of plants native to Germany might reveal  how they are different from today’s varieties or how genetic strains moved over time, as was the case with a tulip native to southern Europe spread north by garden enthusiasts beginning in around 1550.⁵ This type of work is just beginning and fraught with issues about sacrificing even small portions of such old specimens, but techniques are improving, yielding better results while using smaller samples (Figure 4).

The Harder herbarium is a hybrid existing between the worlds of science and the humanities. Comparing it to the few other herbaria from the same region that also have painted additions would likely yield more information on these volumes.  At the same time, this is a valuable scientific resource since it could be used not only in genetic research but in studying the history of garden plants growing in this area.  Thus this volume is an exemplar for research bridging the gap between the sciences and the humanities in fascinating ways.   

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Notes:

¹ Johnson, K. R., Owens, I. F. P., & The Global Collection Group. (2023). A global approach for natural history museum collections. Science, 379(6638), 1192–1194. https://doi.org/10.1126/science.adf6434

² Egmond, F. (2017). Eye for Detail: Images of Plants and Animals in Art and Science, 1500-1630. Chicago: University of Chicago Press.

³ Benkert, D. (2016). The ‘Hortus Siccus’ as a focal point: Knowledge, environment, and image in Felix Platter’s and Caspar Bauhin’s herbaria. In S. Burghartz, L. Burkart, & C. Göttler (Eds.), Sites of Mediation (pp. 211–239). Leiden: Brill. https://doi.org/10.1163/9789004325760_010

⁴ Andel, T. van, Vos, R. A., Michels, E., & Stefanaki, A. (2022). Sixteenth-century tomatoes in Europe: Who saw them, what they looked like, and where they came from. PeerJ, 10, e12790. https://doi.org/10.7717/peerj.12790

⁵ Stefanaki, A., Walter, T., & Andel, T. (2022). Tracing the introduction history of the tulip that went wild (Tulipa sylvestris) in sixteenth-century Europe. Scientific Reports, 12, 9786. https://doi.org/10.1038/s41598-022-13378-9

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Feature Image: Selection of digital herbarium images.