herbarium sheet

Collected on this Day in 1946

It is that time of year when old fields across western Pennsylvania are painted yellow.  

Collected on September 15, 1946, this specimen was found in New Baltimore, Somerset County by an influential curator of botany at the museum, Otto Jennings. There are many species of goldenrod (in the genus Solidago) in our region. They are often associated with runny noses and sneezing from fall allergies (hay fever), but don’t blame the goldenrods!

Their relatively heavy pollen rarely becomes air-borne, but rather these plants are insect-pollinated. Wind-pollinated species, like ragweed, are more likely your culprit. This specimen pictured here (split between two herbarium sheets) is Canada goldenrod (Solidago canadensis).  

Canada goldenrod is a fall-blooming, native species common throughout western Pennsylvania. However, it was introduced to Europe and Asia for use in floral arrangements and gardens and has since become an invasive weed in other parts of the world.

Botanists at Carnegie Museum of Natural History share pieces of the herbarium’s historical hidden collection on the dates they were discovered or collected. Check back for more!


Utah Valley State College Herbarium

The Utah Valley University Herbarium (UVSC) was established in 1987 as a research and teaching facility. The initial herbarium collection consisted of botanical specimens collected by Dr. James G. Harris, Professor of Biology, whose research focuses on a wide range of habitats including the deserts of the San Rafael Swell, high elevation mountain peaks (i.e. Mt. Timpanogos, Mt. Nebo, and the Deep Creek Range), as well as arctic regions of North America and Greenland. Currently the herbarium houses over 17,000 accessioned herbarium sheets, with an average of 1,500 specimens being added to the collection each year.


I found this pretty entertaining. Drosera is a genus of carnivorous plants that catch insects in a sticky inescapable mess. You should look up photos of live ones because they can be quite spectacular. But when their ready to flower, to cater to pollinators (as opposed to killing them) the flower on a stalk rises high above the danger. But I guess whoever mounted this didn’t notice the difference and mounted stalks of other plants to the base of these drosera. Talk about botanical stowaways.

For my BFA thesis, I’ve been Illustrating and writing a guide to aquatic invasive plants. My process for each illustration usually starts with an herbarium specimen. I don’t have access to living plants right now, so herbarium specimens are the next best thing.

An herbarium specimen is a dried pressed plant used as a historical account of what plants were growing where at what time and what they looked like. For my purposes, I am most interested in what the plants look like. I need to get a close look at all of the identifying characteristics.

First, I will leaf through (pun intended) all of the available specimens of a particular species. Sometimes there are a hundred or more specimens. This plant, Egeria densa, actually only had one specimen available at the Cleveland Museum of Natural History, where I’ve been working on my thesis. After picking out specific specimens and deciding which pieces to draw from on each herbarium sheet, I sketch out the plant.

In this example, the herbarium specimen was covered in dirt and sand, which made it hard to see the details. While sketching, I mainly just wanted to figure out how many leafs were where and in what shape. I also may simplify the original plant specimen, cutting out extraneous details.

After the initial sketch to help me figure out what I’m looking at, I make a clean pencil line drawing. In this step, I reconstruct the plant, making it look more alive and fresh, instead of dead and dried up. I also add structural details, like a flower, that may have been missing in the specimen.

After I’m happy with the line drawing, I move to ink. I place the pencil line drawing under a sheet of vellum and ink the line work with a 005 micron. When the line work is done, I remove the pencil drawing from underneath the vellum and start stippling. The stipples build up value to show texture and light on form.

The ink drawing shown above is almost finished. I still have to add the flower! When it’s all done, I’ll scan it in, clean it up in photoshop and place it in the layout for the guide.

So that’s what I’ve been working on for the past few months! I have to draw 37 of these things all together. I have A LOT of work to do! Hopefully it all gets done by May 5!!