A trip to the herbarium and the mounting room

Yesterday Daniel gave me a look at the progress of some of the specimens we co-collected this year.  Getting from the field to the herbarium is a long process.  We looked at specimens that we collected in Texas in April 2011.  Here are some:

It's interesting to look at specimens after fieldwork since each one triggers a memory of a unique ecosystem.  Many we collected were from Balstrop, TX which you will recall burned this summer.  We guess that many of the trees and flowers we collected were burned in the recent wildfires.  This plant, an Onosmodium helleri is endemic to Travis and surrounding counties of Central Texas.  It was found on a friend's property.  In the herbarium there were only six other specimens of this plant, most from the late 19th Century.  So this was a good addition to the collection.  Thanks Malcolm and Charlie. 

The process of preserving and mounting botany specimens takes months. 

After collecting, pressing and drying them, the specimens were placed in a freezer for three days to kill any bugs.  Bugs are the  enemy of any herbarium - they can devastate a collection.  Then the preliminary in-field identification is verified or corrected which can be an easy task or a time-consuming process involving research in books and/or in the herbarium.  Once identified, a detailed label is created naming the plant genus, family and species, telling the location (State, county, road, GPS coordinates, description of terrain and other relevant information), the dates of collection and identification, the botanist who ID'd the plant, and the collector(s).  In the mounting room it all comes together, the plant specimen, the label and a unique bar code.

Here is one I was happy to see because it made me recall the nearby town, the river and the beautiful cottonwood trees that were filling the air with cotton.  The branches were way too high to reach but luckily there was some recent windfall which yielded a rather lovely specimen:

Pretty isn't it?  I like knowing that it will be in the herbarium in perpetuity for scientists anywhere to access and study. 

Here is how the specimens are mounted before they are stored.

Glue is drizzled in a fine stream all over the back of the specimen.  Then using tweezers it is carefully placed on a sheet of acid free paper.  The label and bar code are affixed, as well as a packet for seeds.  The label always goes in the lower right hand corner.  In the field we try to keep that in mind when cutting and pressing a specimen.  It helps to leave room for the label.  Then the specimen is covered with wax paper over which weights are placed.  These are removed when the glue is dry.

Only then does the specimen get filed.  The herbarium consists of several floors of temperature-controlled sealed rooms full of huge cabinets.  The cabinets are in deep columns.  To enter a stack you have to crank an opening and then walk in to the long row of cabinets.  All flora are arranged by family, then genus and finally by species.  Dates are irrelevant.  In one file folder of cottonwood, for example, there might be specimens from the 1800's mixed with specimens from this year. 

And that is today's herbarium tour.  Any questions? For more on how specimens are pressed and dried see the June 20 entry on A Primer on Preserving Specimens.