The only herbarium in Baja California celebrates its 35th anniversary

Tiempo de lectura | Reading time: 5 minutos

By Antonieta Valenzuela


What is a herbarium? It’s a scientific plant collection for preservation that is used to identify and catalog plants; in a few words, it’s a plant library.

“Herbaria are important collections because they work as evidence of plant species in different places, in this case in Baja California,” said José Delgadillo, PhD in an interview for this section of Terra Peninsular.

Delgadillo is a Botanic professor at the University of Baja California (UABC); he’s also in charge of the BCMEX Herbarium, located within the Faculty of Sciences of the same university. This past March the herbarium celebrated its 35th anniversary.

He studied Biology at the University of Guadalajara (UAG), and he obtained a PhD in Vegetal Sciences; besides being the curator at the herbarium, he also founded it. A little more than thirty five years ago he decided to begin a scientific plant collection, starting from the basic notion that every territory must have evidence of the presence of plants and, therefore, have exact information of each species.

The herbarium began its operations in 1981 with the purpose of having a plant collection in Baja California, one that included native and exotic species. This has been achieved since it’s the only herbarium of vascular plants in the state to date. The Boojum tree, as a representative plant of Baja California, is part of the official logo of the BCMEX Herbarium since 2013.

Delgadillo mentioned that in the herbarium the plants are numbered and each plant that becomes part of the collection has a unique ascending registration code.

“Nowadays, we have over 15,000 registration codes. If we take into account that there are 2 species per code, then we’re talking about over 30,000 plants in the herbarium including native, exotic, exchanged and donated plants from other states.”

“Inside the herbarium there are currently about 2,000 species from Baja California and its islands, those species in the collection probably represent the 60 per cent of the peninsula’s flora,” he added.

The professor commented that the oldest specimen is from 1934; it’s a type of grass from Arizona, US that remains in perfect condition within the herbarium to date.


Registered locally and internationally, including at the Secretariat of Environment and Natural Resources (Semarnat), the herbarium has a data base that serves the purpose of improving the knowledge of the flora of Baja California and Mexico. In the same way, the BCMEX Herbarium has an alliance with other herbaria in the region, and therefore, a joint data base.

Besides conserving specimens of flora species, Delgadillo emphasized that one of the main functions of the herbaria is to work as a reference tool, and in the case of BCMEX, mainly for academic purposes.

About the process of preserving a plant, he explained that before a specimen becomes part of the collection and it’s included in the data base, first it has to pass through a precise dehydration process, then a preventive fumigation and, at the end, remain inside a refrigerator at minus 15 degrees Celsius (5 °F) between 4 and 5 days to kill the majority of insects.

Some associated researchers from Terra Peninsular, like Sula Vanderplank, have contributed with species for the herbarium, including some plants collected from the Valle Tranquilo Nature Reserve. As he explains, all foreigners must duplicate by law all the collections obtained during field trips.

Delgadillo is passionate about the flora from Baja California. He has collected plants for the herbarium during his filed trips and whenever it’s possible. He told us that being a curator requires patience, work and passion. After 35 years of being in charge of the herbarium, he added that it’s a project of relevance for science and the state, and that there’s still a lot to do.

Even though the BCMEX Herbarium doesn’t have an official website, Delgadillo manages the website Baja Terra Ignota, where he publishes about flora species and related topics.

The people interested can visit the herbarium and consult the data base, only with academic purposes. For more information, please contact Dr. José Delgadillo via email:

Coming up soon, Dr. Delgadillo and Terra Peninsular will work together in a plant sampling and collection in relevant conservation places in Baja California.