On Saturday morning I was lucky enough to spend a couple of hours in the Oxford University Herbaria, with its curator Dr Stephen Harris. The first time I saw herbarium sheets was at the Millennium Seed Bank, where they are called vouchers as they ‘vouch’ for the identity of plants. They are, in essence, plant ID cards.

A herbarium is a collection of these sheets, whether they were bound into a book by one dedicated individual, or have been amassed into huge collections. The Oxford Herbaria are the Druce-Fielding herbarium which belonged to the former department of botany, and the Daubeny herbarium from the former department of forestry. Today they contain around a million specimens; to put that into context, the largest herbaria contain around 12 million specimens (e.g. Kew and Paris).

The earliest collected plant specimens here date back to around 1606. The oldest herbarium in the world is in Kessel, which only holds 10,000 specimens. The oldest specimens are in Italy, and date back to the 1580s.

The earliest herbarium in the UK is here, with specimens gathered in Northern Italy by a Capuchin monk, Gregorio Reggio. It is very well-preserved, and is currently on loan to the Treasures of the Bodleian exhibition until 23rd December 2011. If you’re doing your Christmas shopping in Oxford then try to drop in – the exhibition is free and contains other publications of botanical interest.

I have photos of some of the specimens that Dr Harris had on display for us, all of which have interesting stories attached, so I am going to blog about them this week.

Jacob Bobart the Elder

This is a page from the herbarium of Jacob Bobart the Elder, the first head gardener of the Oxford Botanic Gardens (known then as the Oxford Physic Garden). As paper was expensive, multiple specimens are mounted on one sheet. The specimens are bound into a book, organized in alphabetical order of their polynomial name. This was before the acceptance of the binomial naming standard, and polynomial names were essentially a complete description of the plant’s characteristics in Latin. They could get quite long.

The modern preference is for herbaria to consist of loose sheets, with only one specimen per sheet. Jacob Bobart the Younger (the son of JB the Elder) annotated his father’s work and also made his own, which is dated around 1670 (herbaria are generally collected over time).

Indian fig

Maize

These two sheets, of the ‘Indian fig’ and of maize, illustrate a problem that persisted for around 200 years. As plants were transported to the various colonies, their origins became unclear. These plants were through to come from Asia, rather than their native America. Part of this may be due to sloppy record keeping, but it’s also probable that the information was considered too commercially sensitive to share.

The Indian fig specimen is one of my favourites, as it was preserved with its spines intact!

A Dutch specimen

This specimen has been laid out in the Dutch 17th century style – they liked to cover the cut ends of the plants with an urn, and the ‘tombstone’ label is also distinctive.

Water lily

This one is a Victorian favourite – the water lily. Note that only a section of the huge leaf has been preserved! Apparently it’s successful cultivation proved elusive in Britain, until the head gardener at Chatsworth discovered that a constant water temperature is the key.

Linnaeus

And this specimen was collected by Linnaeus himself, in his native Lapland. This species has been found in the UK, on one mountain in Scotland, where it is believed to be a glacial relic. Linnaeus didn’t really invent the binomial naming system we still use today, but he championed it and led to its widespread acceptance.

There’s plenty to see, so stop by tomorrow for another batch of specimens from the herbarium :)