- Massey JR. 1974. Chapter 31: The herbarium. In Radford AE, Dickison WC, Massey JR, Bell CR. Vascular Plant Systematics. Harper and Row Publishers. Retrieved from http://herbarium.unc.edu/chpt31.html
When you first learn about stacks of plant specimens housed in herbaria, it is tempting to envision these collections as quiet, inanimate storage spaces. You can imagine the smells of paper and dust, the quiet hum of florescent lights, and imposing rows of tightly shut cabinets. Indeed, many California herbaria are currently fated to this state with the shelter-at-home order still in place, but this was not always the case. Herbaria can be bustling hubs of creating, tending, discovering, and learning, and without constant care and curation, years of hard-earned data can be imperiled. Even when students learn from home and researchers keep to their desks, herbaria still require resources and attention.
Herbarium specimens are like delicate archival books: subject to rot, insect infestation, and general decay when not properly cared for. This is particularly important in warm environments, where heat and humidity can accelerate deterioration, the growth of mold, and the proliferation of pests. In California, one such infamous pest is the cigarette beetle, a tiny but destructive creature that can consume all plant matter on an herbarium specimen (and leave holes in the mounting paper, to boot!). Book lice are even smaller pests—about the size of a grain of sand—that nevertheless have huge appetites and can munch through herbarium specimens at startling speed. Flowers and fruits, perhaps the most important features for conclusively identifying most plant species, are often the first parts to be targeted.
Controlling pests is a continuous battle. Historically, curators and collections managers used pesticides, but since these substances are often toxic to humans as well as pests, modern managers typically rely on integrated pest management: maintaining an environment that prevent pests and controlling outbreaks by freezing infected specimens. While safer, this approach takes a lot of work. The environmental conditions of the herbarium must be monitored for appropriate temperature and humidity, and cabinets must be constantly checked for new infestations. Once an outbreak is discovered, the cabinet must be sanitized and its entire contents frozen for several weeks. Without regular and careful observation, major and irreversible damage can occur in a relatively short amount of time.
Herbarium curation also includes repairing damaged specimens, organizing specimens that were pulled for research or other use, and—in most collections—keeping up with the backlog of specimens that have been deposited in the herbarium over time. (The latter task can be surprisingly formidable; large herbaria may have full-time staff whose sole responsibility is to mount specimens!) In addition, when not sheltering-at-home, herbarium staff lead tours of students and naturalist groups, and they help researchers, land managers, and the public find the botanical resources they need. All in the day's work for a curator of one of the world's most important sources of botanical data.
Don't let the tall, steel doors and stacks of papers fool you; herbaria are active spaces that need constant, careful support to preserve the irreplaceable data held within. These institutions safeguard centuries of botanical knowledge and hold the keys to countless future discoveries.
While many herbarium collections across the state are sitting in silence, their curators, data managers, technicians, and volunteers are doing quite the opposite. Herbarium databases are a flurry of activity as faculty, staff, and citizen scientists take advantage of the past years of digitization efforts to create and expand herbarium specimen data. Thousands of the >560,000 specimens imaged by the California Phenology Network since January 2019 still need to have their label data entered in the database. These and many thousands more still need to be georeferenced—assigned latitude and longitude coordinates from the location data on the label. Each of these tasks can be done remotely, thanks to the California Phenology Network's online database (CCH2.org) and citizen science platforms like Notes from Nature.
Volunteers have especially showed up during these difficult times—a true testament to the passion and determination of hundreds of citizen scientists across the globe. (A few extra hours to spare can't hurt, too!) The graph below shows the daily number of transcriptions (specimens that have had their label data entered) on Notes from Nature since mid-February. Since the beginning of the shelter-at-home order in California (red line), transcription numbers have shot up and now remain consistently higher than before.
Students and staff who previously spent hours imaging specimens now find themselves at the computer, learning to transcribe label data and georeference specimen records. Weekly "Zoom office hours" bring these dedicated workers together from across the state to check in, ask and answer questions, and build synergy. In the words of the project manager: "We may be isolated, but we're not alone."
As California begins the long road to re-opening, on-site digitization activities at herbaria will slowly resume at a currently unknown rate. One thing is for sure: the herbarium community and plant enthusiasts are certainly not putting their time to waste.
To learn more about getting involved in at-home digitization activities, contact the CAP project manager, Katie Pearson.