BIO
201: Botany
THE HERBARIUM
HERBARIUM = A collection of pressed and dried plant specimens developed for research purposes
1) Reference collection for identification of plants
2) Specimens provide information on the location and time a plant grew in the past
information can be used to assist in the predicted future for a plant species
3) Vouchers for flora projects
a) distribution of a species
b) information on what species at a location
4) Voucher specimens of research projects
a) ecological surveys
b) anatomical and morphological research
5) Reference collection for teaching botany classes
Over 350 herbaria in the world
The oldest herbarium is: University of Bologna, Italy (1570)
Most herbaria are at universities and colleges
Others are located at Museums:
world's largest at Paris Museum – 7 million
In South Carolina we have:
Clemson University - 60,000 specimens
University of SC - 100,000+ specimens
Newberry College - 20,500 specimens (3rd largest in SC)
About 20 other herbaria around the state
VALUES OF A PLANT SPECIMEN
1) The specimen can be verified as a particular species.
2) Provides a permanent record of the presence of a plant in time and space.
date of collection important (ex documenting global warming)
place of collection important (can return at a later date to see plant)
3) Together the plants provide ecological information.
Part 1: Collecting in the field (ideally)
1) find representative plant or branch
2) need to collect with flowers and/or fruits
3) avoid specimens with heavy insect or other damage
4) collection large/small enough to fit within newspaper
5) can press immediately or put in bag with water for later
Part 2: Drying the specimen
1) press into newspaper in press
2) have several leaves facing both upward and downward
3) press need to have mechanism to allow air flow through
4) use dry air at (best temp) 55oC
5) drying takes 1-4 days
Part 3: Identifying your species - resources may include:
1) you already know it!
2) use a taxonomic key
3) the herbarium: specimens in the collection
4) make use of your nearby botanist
Part 4: Quality specimens need a label
1) specific location that can be found with a map
2) date of collection
3) collector
4) scientific name of plant
May also include information on:
5) habitat information, including soil and moisture
6) habit of plant
7) collection number
Part 5: Producing a quality herbarium specimen:
1) Specimens glued on sheets of 11x17 paper
a) make specimens so they can be reviewed
b) keep all material together, yet visible
c) include information on the collection
2) Include a label so specimen has history
3) Databasing specimens allow for access via the internet
* this is a new development
Several concerns relative to maintaining a collection
Have it organized so specimens can be found quickly
a) alphabetical order by family, then alphabetical by genus
b) families in systematic order; evolutionary scheme
Preserve to prevent damage -- store in cabinets
a) specimens loose color when exposed to light
b) changes in humidity can hurt plants and glue
c) insect damage can be severe (eat specimens)