I am a co-op student starting my fourth and final work term. This term, I am working at the Canadian Museum of Nature. One of my favourite things about being a co-op student is the opportunity to gain an understanding of how different jobs contribute to society, science and our understanding of the world. In previous terms elsewhere, I learned about innovations in pest management, environmental monitoring methods and how products of biotechnology are regulated to ensure the safety of Canadians and the environment. Now I work at the Canadian Museum of Nature in the National Herbarium of Canada.

A woman stands in an aisle between cabinets, waving.
This picture represents about half of the herbarium. Cassandra Robillard, a botanical illustrator and former intern at the herbarium, provides a sense of scale among the cabinets. Image: Tera Shewchenko © Canadian Museum of Nature

The herbarium is like a library of plant specimens. I was immediately impressed by its size; it’s pretty big. There are hundreds of cabinets taller than I am that are filled with folders and folders of specimens. Travelling around the herbarium to find specimens of different species is good exercise!

A specimen of Castilleja raupii (CAN 230262) on a herbarium sheet.
This Castilleja raupii specimen (CAN 230262) was collected in 1854 and still retains some its red colouring. It was collected near York Factory, a small settlement in northern Manitoba. Image: Tera Shewchenko © Canadian Museum of Nature

The herbarium houses a cornucopia of specimens that represent a multitude of different species from across Canada and around the world. I was amazed to see that some of these specimens were collected as long ago as the 1800s and still retain their shape and even some colour. It is truly remarkable to see blue flowers or red leaves on a plant that was taken out of the ground 150 years ago.

All plants in the herbarium have an identifying number (called a CAN number in reference to its prefix), and a label. The label is very important because it includes the species name of the plant, where and when it was collected, who collected it, and sometimes a description of the habitat it is collected from. This allows people who may in the future use the specimen for research to easily obtain information on the specimen they need. I also often make use of this information when looking through the herbarium for requested specimens, and have a good appreciation for a detailed label.

Tera Shewchenko.
Tera Shewchenko in the herbarium. Image: Fatima Omar © Canadian Museum of Nature

The herbarium is an incredible resource for research.

It can be used as a historical record of what plant species grew where and when. Comparisons can be made between specimens found across time to see how changes to an area are affecting it. These changes can be anything from global warming to the construction of a new neighbourhood in a previously preserved area.

It is also used by researchers before they go out into the field as a way of getting familiar with different plant species they may encounter. They are able to look at specimens in the herbarium and learn how to identify them out in the field.

When people come back from the field with plants they have collected, it also serves as a reference for them be sure they have correctly identified a plant as a certain species.

It is also a good tool for education. From working here, I have gained a new understanding and appreciation of the diversity of plant species and their distribution. Before working here, I never would have thought that there was such a diversity of plant species in the Arctic!

I have also learned that plants come in all kinds of shapes and sizes. The shapes of plants are really fascinating. Some of my favourite shapes are the fan-shaped Ginkgo biloba leaves and the tranquilizer-dart-like flowers of the pretty shootingstar (Primula pauciflora).

A specimen of Taraxacum officinale (CAN 591805) on a herbarium sheet.
This common dandelion (Taraxacum officinale, CAN 591805) is special because it is fasciated: the plant has flowers that are two-headed, and have a crested shape and thick stems. Dandelions sometimes do this; no one knows why for sure, but it may be caused by a bacterial or viral infection. It’s another neat thing I learned at the herbarium. Image: Micheline Bouchard © Canadian Museum of Nature

I also found the crested shape of the flowers of a fasciated common dandelion specimen very neat (see the flowers shown at right on the thick stems). Most dandelion flowers do not take this form, in which the flower is shaped more like an oval than a circle. The shape is caused by an anomaly in the flower’s development known as fasciation, which is thought to be caused by a bacterial or viral infection of the plant. The condition also causes the stem of the plant to become thicker and may cause multiple fused flowers to form from a single stem instead of a crest. I have a lot of interest in both development and disease, so I found this condition intriguing.

Smaller plants have interesting shapes as well, though you often have to use magnification to see them. Mosses reproduce sexually through capsules that release spores. These capsules come in several different shapes. Some are sac-shaped, some look like umbrellas and still others look like golf clubs. The varying shapes can be used to differentiate between different mosses and are very beautiful to look at. I find they give the moss a very alien and elegant appearance.