Green scene

Herbariums help us travel through time


While further researching the New York Botanical Garden’s exhibit “What in the World is a Herbarium?” I was privileged to speak with Matthew C. Pace, the assistant curator of the William and Lynda Steere Herbarium.

I chanced to ask him what he felt the most exciting part of his job was. Without blinking, he replied that working in a herbarium is “like being in a time capsule” where you are actively involved in work begun by botanists from many different time periods in many different parts of the world.

This is not some musty library where materials sit forever undisturbed, but instead are part of an ongoing search for relationships between plants, between plants and the rest of the natural world, and between plants and humans. Very often the sheets were submitted with notations on the margins or together with journals from a collecting expedition making it feel “as if I were having a conversation with these explorers.”

Last week’s column did not touch on the uses of a herbarium, and so I must return to that issue today.

First, it is important to create a baseline of all of today’s plants. Plants as well as animals become extinct, and we need this information to fully understand climate change, reasons for habitat loss, and the activity of invasive species. Also, plants tend to grow in communities, and understanding these interactions is important for ecological health.

Ethnobotany is the study of how indigenous people — indeed, all people — utilize the plants in their environment as food, medicine and materials for clothing, housing and other needs. The botanical garden’s Michael Balick cofounded the Institute of Economic Botany in 1981 and has studied peoples all over the world in tropical, subtropical and desert environments.

Ina Vandebroek, also at the garden, studies Caribbean communities in New York City. Each indigenous community contributes vast amounts of botanical knowledge about their local flora.

Most life on this planet depend on plants — the exceptions being various bacteria and archaea, which inhabit extreme environments like boiling black smokers on the ocean floor which do not require oxygen for their metabolism. This being the case, we must understand the plant physiology with an eye to adequately caring for a densely populated world.

Modern DNA studies are elucidating evolutionary history and relationships far better than the older method of depending on structural similarities. For example the once large lily family — including what we still call lilies, asparagus, onions and agave — are really 16 different families.

Just as people are not identical, so too, plants show some variability in the structure of leaves and flowers. Researchers, using multiple herbarium sheets of the same plant, can establish what are known as type specimens. These become the yardstick for the expected appearance of a particular plant, and in turn, become the standard used for guidebooks and botanical illustrations.

Dating materials from archeological digs can be tricky. But now, pollen grains, seeds and plant vestiges also are routinely surveyed. Herbarium studies can help identify plant remains, which aids dating as well as ancient plant usages.

Forensics also require accurate plant data. Plant remains from a suspected crime scene can yield valuable information about the actual site of a crime as well as the time of the year that a crime had occurred. I might read too many detective novels!

Botanists frugally used whatever paper was at hand to create specimen packets to hold seed or plant fragments. Cultural historians can find old advertising, ballots and other materials to broaden their understanding of a past era.

Chemical analyses of plant fragments from bygone eras can elucidate past environmental conditions. Studies on lead and other pollutants as well as information about changing carbon dioxide levels in the air all are vital.

Herbariums act as an educational resource providing accurate identification of local species, garden club material, acting as a conservation center, and providing samples for museums and educational exhibits.

If the possibilities of this work excite you, volunteer opportunities exist from the comfort of your home. The older labels were handwritten and must be transcribed to a typed format before digitization. 

You can visit, and after a short training video, view handwritten labels uploaded sequentially to your computer, and you can enter the information on a template.

Safeguards in the program ensure the accuracy of the new transcription. Digitization cannot progress without these transcriptions, so the work is invaluable as well as interesting.

Visitors are invited to see the exhibit at Ross Hall and actually enter the herbarium on Earth Day, April 22 at noon.