Mounting Botanical Specimens

One of the things I mentioned in my last post was a trip to the James F. Matthews Center for Biodiversity to pick up specimens that needed to be mounted. Many of you have expressed interest in this task so I figured I would document and discuss some of the process.

Basic set up

Mounting for me at home is fairly easy since I have a studio space. Above you see the basic set up: the plant, a tub of slightly watered down glue, some brushes, a small bowl of water, and to the right a piece of paper on cardboard. To my left out of view is a box of a few handy tools such as small scissors, tweezers, linen tape, some tissues, and a stiff brush for cleaning up dirt. And, of course, the essential radio. Now I know that my artist friends are going to ask what type of glue? We use Ph neutral PVA made by Lineco.

making decisions

So here is the first specimen. Opening the paper up is like opening a gift because I never know what is going to be inside. This is a grass and, as you can see, there are several pieces here and they will not all fit on the paper so decisions have to be made. The most important part of any specimen is the flowers and fruit so I will choose the piece that has the most of those structures. There are also lots of root clumps so it will be important to show that. All the specimens contain the stems and some leaves.

placing the specimen

Here is the piece I decided should be mounted. It shows a good clump of roots, three flowering/fruiting structures, and leaves and stems. I put it on the paper to make sure it fits and then I will need to brush the dirt off the paper and remove the dirt from the roots. It is very important when deciding the place and position of the plant to remember that other things will be put on the paper such as the scientific label, accessioning number, and other information needed for the database. So space is needed in the lower right and left corners and the upper left corner because that is where this information will be placed.

cleaned roots and pouch

Above you will see a stiff brush that was used to brush the dry mud off the specimen’s root clump. There were also some lovely flowering/fruiting structures on the other plants not selected so I cut off two of those and made a side pouch which will also be mounted with the plant. If possible, it is always good to include some additional flowering/fruit structures in a protective pouch because, especially in this type of specimen, they can fall off the mounted specimen if not careful. I have circled the roots and additional structures in red so they stand out easily against the busy newspaper background.

Glue is applied carefully to the larger parts of the specimen and then carefully laid on the paper. The paper used is also a very particular paper especially made for this purpose. It is an archival paper measuring 11.5″ x 16.5 inches.

mounted specimen: Secale cereale

Above is the finished specimen. Notice the pouch off to the side and the scientific label. The label always goes on the bottom right and contains information such as the name of the plant, where it was collected, a description of the surroundings, the date, and who collected the specimen.


Sometimes I get very lucky and a specimen is pretty much ready just the way it was pressed like this Sambucus. These flowers are very delicate and, if you look for the red circles, you will see some flowers have fallen off. I will collect these and make a pouch for them as was done with the grass.

mounted Sambucus

Here is the mounted Sambucus. I marked the pouch with a red x (not really, just in this presentation) and there is also a red arrow pointing to something that I call a bridge though I am sure there is a more technical name. These are made out of archival linen tape. You cut pieces very thinly then wet them ever so slightly with water (this is one of the functions of the small bowl of water with the small brush. The other function is to clean up excess glue that may have gotten on the plant in the process of mounting it). The bridge is to anchor a part of the plant that will not stick to the paper with the glue, such as a woody stem. If you look at the leaf above the pouch you will see that it looks lighter. That is because this is the other side of the leaf. When mounting, you want to try to show both sides so it is always a good idea to turn one leaf over if none have naturally positioned themselves that way.

weighted specimen

The last thing to show is what happens after the plant is mounted. It is covered with wax paper and small weights, which are actually pieces of hardware. Weights are placed to make sure the plant stays put while the glue sets. The plants sit out for a least a day then will be accessioned into the collection.

For the Love of Weeds ~ part 2

Yesterday I spoke of my love of weeds and mentioned that I am involved with collecting wild plants for an organization. So I will talk a bit about this today.

Where I live, the county is steward to an herbarium, which is a collection of wild plants that are preserved for the purpose of research.  I am a member of an organization called Central Carolina Master Naturalists, a group that is trained in different areas of natural history then does volunteer work in a particular field or fields. My main area of interest is botany and I volunteer with the herbarium.

Plant Press
A plant press

One of the most welcoming feelings I had after moving here was going to the herbarium and seeing a plant press tagged with my name for me to use.  Let me take a moment to address something very important: there is protocol for collecting wild plants.   Though I was collecting “weeds” like I used to which were plentiful, I was also collecting other specimens so I had to follow some rules. First, I had to have permission, which came from the herbarium itself. As a scientific entity, I could collect for them as long as they approved of me doing so. Second,if it was an endangered plant, it could not be collected at all. I simply took a photograph of it and logged information about it.  The other thing is there has to be at least ten visible specimens of what you are collecting so there is assurance of not removing something that is not prolific.

So as to the actual collecting itself, you need to try to get as much of the plant as possible which means preferably something in flower (also something that had gone to fruit or seed is good) a few leaves, and roots. The specimen is then spritzed with water and put into a plastic bag and sealed to maintain the moisture. Then the location has to be recorded and now this is done with GPS coordinates as they are the most accurate. Other conditions are noted: the surrounding landscape, other plants in the area, any information added is useful.

A mounted specimen with label. The plant is Clematis virginiana.

When I got the plants home, I had to position them in the press so they would dry out in a way that when they were mounted, different parts of the plant could be studied.  Then, if I did not know the plant (and most times I did not), I had to key it out.  Keying involves looking at very specific aspects of a plant such as flower parts, arrangement and type of  leaves, and a variety of other physical attributes of the plant.  Different guides have different criteria for keying but these aspects are pretty universal.  I was going to talk more about keying in this post but it is so involved, I have since decided to devote a whole post to just that topic so that will come over the next few days.  The name of the plant is added to the notes taken while in the field and placed with the plant in the press. When the press got filled up, I brought it to the herbarium where the plant ID was verified (or corrected) by a botanist, mounted, labeled, accessioned, scanned, and filed. To the right is a plant I collected and I am happy to have learned that this particular plant had not been collected in the county in 50 years. So there is my contribution to local science! 

Field work 2The herbarium is part of a larger resource center containing a variety of natural history items and scientific data collection so there are several projects that go on. Some of the other things I have helped with are forest assessments, moth nights, and endangered species counts. The photograph on the left is one such event where we were preparing to start a count for the Schweinitz’s sunflower (Helianthus schweinitzii).

I will end this post with a brief statement on use of botanical names vs. common names. I know it can be really annoying to be talking about a plant and some showoff has to throw out the Latin name but I cannot stress how important and useful it is.  When I first started to collect, my field partner was talking about a Tamarack and I said that I knew of a similar tree called a Larch. Neither of us knew what the other meant but as it turned out, we were both talking about the exact same tree (Larix laricina).