This is the largest collection in the Herbarium BCN and it currently has over 350,000 specimens. There is a good representation of materials from the Pyrenees, the Ebro Valley, North Africa and some tropical areas of South America. In terms of taxa, there is a broad representation of the genera Artemisia, Delphinium, Dianthus, Euphorbia and Thymus. There are also a number of historical collections, such as those of P. Font i Quer, T. M. Losa, J. Planellas, Fr. Sennen and J. Texidor. In addition, there is a complementary collection of fruits and seeds, and ethnobotany collection and a teaching herbarium that can be consulted at the CRAI library of Biology and the CRAI Pharmacy and Food Science Library (Diagonal Campus) and also at the virtual herbarium.

 
The plants are dried and stored on herbarium sheets labelled with the correct identification. The sheets are then put in lined cardboard boxes. With the exception of some historical collections stored separately, the sheets are arranged in alphabetical order by species.

This is one of the basic reference herbariums in the Flora Iberica project and it plays an active part in the ORCA project, which addresses the mapping of plants in the Catalan-speaking territories (Catalan Countries). 

In the early nineteen-nineties, the first steps were taken to computerize this collection and now a significant part of this information can be consulted at the database.

Moreover we are proceeding on the digitization of type specimens, some of the historical collections and specimens of threatened species or from protected spaces. These images can be consulted as a part of the virtual herbarium.