Tuesday, January 29, 2019

Herbarium sheet maintenance

In college as an undergrad I took two classes in the Forestry department to study Dendrology, or the study of woody plants. We prepared a collection of herbarium specimens for one of the classes. These were two of my favorite classes in my entire college career.





My herbarium collection has been in a couple of shirt boxes under the bed for many years. I realized last summer that I was going to lose this collection if I did not take care of it. I bought archival boxes to store the sheets. Amazingly, most of the plant material was still in decent condition.



There was an additional step to take that I thought could wait until winter. I found a great resource from the National Park Service on maintaining herbarium sheets here.



Like most people with a small collection, I do not have enough freezer space to put the boxes into storage for a week to kill any pests. But I do live in a cold climate during the winter, and we are in the middle of a real cold snap. So, I am putting the boxes into a garbage bag, and the garbage bag into a big storage tote, and it is going in my garage, where the temperature should be close to freezing (will verify with a thermometer!). First, though, I am letting the tote acclimate to the cold to try to cut down on any condensation forming and dripping onto the boxes.





I love looking back through these. How in the world did I misspell paniculata? I lost two points for that. :)


Some trees in this collection were young when we took the samples. A few years ago, I went back to one of the parks where we had collected them, and I didn't recognize any of the trees there. They had grown. A lot... as trees do. And I would not be surprised if some of these trees are long gone. I have a new appreciation for a collection like this, a window on a particular place at a particular time. Forests (even urban ones) are not stagnant. They are ever-changing, and the species makeup and the number of trees can be very different in a matter of decades.


Anyhow, this is a nice way to spend a very cold winter day. I will try to update with how this experiment goes.