Virtual Tour of a Typical Herbarium Specimen

Barcode: A unique code is applied to every specimen entered into WIS’ central database.  In this case ‘v’ indicates that the specimen is a vascular plant, and WIS is our herbarium’s official acronym.  No two specimens anywhere in the world will have the exact same barcode, which minimizes confusion and makes retrieval of this specimen much easier than it would have been in the past.

Color Card: Since many of the Herbarium’s physical specimens have been digitized (photographed with a digital camera) and will be viewed on the internet, it is important that every specimen image contain a standardized color card.  The card is not mounted on the physical specimen, but simply set down on the specimen when it gets photographed.  Different computer monitors, software, and web browsers display colors differently.  The color card can be used to calibrate a computer monitor or make color adjustments if the specimen image is printed.

Pressed Plant: Of course the main object on a herbarium specimen sheet is the pressed plant specimen itself.  These are collected in the field, pressed in a standard herbarium plant press (usually between pieces of newspaper), dried at low temperature, then carefully arranged and glued to a heavy sheet of acid-free paper.  In some cases specimens may even be sewn onto the sheet with needle and thread.  Plant mounting is an artform unto itself, and a good plant mounter takes a little extra time and effort to arrange the specimen so that the top and bottom of leaves is visible, the specimen is not crowded on the sheet, but leaving enough white space for additional items to be mounted with the specimen as well.

Ruler: All digital images of herbarium specimens should have a standard ruler or scale bar added to the image.  These are not part of the physical specimen.  Scientists who download a specimen image use the ruler to calibrate their own software for taking measurements, or use the ruler as a scale so that they can enlarge the specimen image to it’s actual size.

Handwritten Annotations: In most cases the modern specimen labels are typed and indicate the original identification of the specimen.  Here we see that the plant was identified first as Dryopteris colombiana.  However, scientists who inspect the specimen at a later date may ‘annotate’ the specimen with a different species name.  The reasons for doing this vary.  In this example, a botanist changed the name on the specimen to Thelypterisoligoarpa, and also indicated that the specimen is an isotype of Dryopteris colombiana.  He or she did this by writing directly on the herbarium sheet, a practice that is discouraged, but not uncommon.  Interpreting old handwritten script can be a challenge for the modern herbarium curator!

Typed Annotation Label: The preferred method for annotating a specimen (i.e., updating information on the sheet) is to glue a small paper label to the specimen.  In the event that the specimen gets damaged and needs to be repaired, this label can be removed and added to a new sheet.  In this case we see that the isotype status of the specimen was verified by M.A. Wetter in September of 2008.

Herbarium Stamp: Most herbaria stamp the specimens in their collection with the herbarium’s name or a logo.  WIS makes use of the university’s mascot Bucky Badger.  If this specimen is ever loaned out to another herbarium, it is more likely to be returned to WIS because the stamp identifies its owner.

Number Label:  This is not a common practice, but some collectors will add a label to their collections which have been numbered by them.  We infer from this piece of paper and the typed specimen label that this specimen is number 998 of a set collected by Herbert M. Smith.

Specimen Label:  Other than the specimen itself, the label is the next most important part of a herbarium sheet.  Here the collector should provide as much information s/he can concerning who collected the specimen, what number has been assigned to this collection, where it was collected, when, a brief description of the plant, habitat, GPS coordinates, other plants gowing in the vicinity, etc.  The example provided here is a rather poor quality label since it provides only minimal information.  However, the collector has at least told us the most important facts about this specimen: it is number 998 of a series identified as Dryopteris colombiana and collected by Herbert M. Smith on an expedition to Santa Marta, Colombia between 1898-1901.