One important task for specialists in a particular plant group, in my case nettles, is to visit national or regional collections and not just rely on the collections of our own institutes, no matter how good they are. As part of a conference and field trip I have just spent a couple of days in the La Paz herbarium. My colleague Nicholas Hind will spend three weeks there identifying plants from the daisy family (Compositae) and running an identification course. There were 92 boxes of unidentified Compositae waiting for him when we arrived!This herbarium was founded by German botanist Stephan Beck in 1984 and currently houses over 400,000 herbarium specimens. The reason why such visits are important both for the specialist but also for the herbarium are that although there is an active inter-herbarium loan system for plants it relies on material being accessioned, mounted and identified. This can be a real challenge to achieve in a country where there are few funds and even fewer botanists. The visit of a specialist allows material that has not been mounted or accessioned, together with unidentified material, to be reliably (one hopes) identified and so used as reference for future identifications.
For the specialist, herbarium visits are incredibly important as they enable us to see material that could not be requested on loan because it has not been accessioned or mounted. This can include potentially new species. It also enables us to make contact with local botanists and to meet and advise students. In my case there was too much material fro me to look at in the two days that I had so I focussed on a group of nettles that I know relatively well, Urera. It consists of only a few species so I knew that I would be able to see most of their material. I was very surprised to find a number of collections of at least two species that may be new, one from the wet Savannah’s and another from the dry forests of the south east.