Wild About Herbariums

When I was a kid, one of my hobbies was collecting specimens of local wildflowers. Any time I went out exploring I’d tuck an old grocery bag into my pocket so that I could gather any new plants that I discovered. With my dad’s help, these new specimens would be carefully identified using a botanical key before I pressed them to dry and mounted them as part of my collection. 

My little childhood plant collection couldn’t compare to the contents of a real herbarium, but the desire to catalogue and understand the natural world creates a common thread between them. 

Herbariums, which are kind of a cross between a library and a museum, can be found at many universities and other institutions such as botanical gardens and museums. In the herbarium, each plant specimen is pressed and dried before being mounted onto a large sheet of acid-free paper. A label is attached that documents not only the name of the species, but the name and date of the collector, the specific location it was collected, along with information about the plant’s habitat and any associated species. Once complete, each sheet is placed into a folder or box containing similar species. Even a small herbarium will contain thousands of specimens.

The first herbariums date back hundreds of years to the Italian Renaissance when they were established in the mid 16th century as teaching resources for Italian universities. While those original specimens have been lost, some collected shortly after the herbariums were established still survive. Under proper conditions, plant specimens can last for hundreds of years. 

At world-renowned Kew Gardens, the earliest specimen dates to 1696, more than 150 years before the Kew Herbarium was established. This mismatch in dates is not unusual as herbariums frequently acquire private collections. As well, herbariums share specimens between different institutions in response to research requests so a plant that was collected by one herbarium may make its way around the world to another location. 

Herbariums are more than a catalogue of plant species. They represent a time capsule that provides a glimpse into changes of species distribution and abundance. Data collected as part of the sampling process also offers an understanding of habitat and geomorphology. Even more critically, herbarium records offer documentation of species that are endangered, extirpated, or extinct. Most importantly, they provide us with an understanding of biodiversity through time.

It’s easy to think that herbariums might be obsolete in an era where citizen scientists are able to instantly document and upload plant sightings to sites such as iNaturalist. Without question, digital catalogues are important and have provided new resources for scientists. However, an online photograph cannot replace a herbarium specimen. Firstly, identifications from photographs are difficult, especially for plant species where identifying features may be small and specific. Secondly, while iNaturalist observations are geolocated, observers are not providing detail into habitat types or associated species in the same way as a herbarium collection would. While both tools are important, research supports the conclusion that the wealth of information captured by herbarium specimens cannot be replicated by online observations. 

This value is demonstrated as genetic research into species taxonomy, evolution, and ecology has increased in recent years. I love iNaturalist and as an amateur, it satisfies my desire to collect and identify my local species, but even the best photograph cannot be sent for genetic analysis. Today, herbariums around the world contain 406 million plant specimens, each one preserving genetic material that can aid future research into issues such as climate change.

Herbariums are a product of western science and consequently, Indigenous voices are often absent from these collections. However, some institutions, such as the University of Victoria, are making efforts to include Indigenous names and other connections through their herbariums. 

All is not well in the herbarium world. In 2024, Duke University, which is home to the second-largest herbarium in the United States, announced it would be closing its herbarium due to expensive operating costs. While the specimens that Duke holds are expected to be dispersed to other institutions, the closure represents a loss of knowledge and institutional memory. 

Although Duke is not alone in closing its herbarium, many other institutions, including Kew, are moving in the opposite direction, working to make their collections more accessible by digitizing them and hosting them online. With collections comprised of hundreds of thousands of specimens, this effort is no small task and is expected to take many years. As a result, many herbariums are relying on volunteers, either in-person (ask your local herbarium if they need help) or online, where volunteers can help catalogue specimens through their home computers. 

It’s been years since I collected any plant specimens of my own. Today, all of my collecting is done with a camera. But there continues to be something magical about herbariums and knowing that a hundred years from now, plant specimens that were collected today will still be available for botanists to learn from as a time capsule that extends across centuries.