Integrative Biology 335:
Systematics of Plants
Preserving and Collecting Plants
Announcements:
A plant collector into her work
Text and Web Resources:
Judd et al., Plant Systematics: A Phylogenetic Approach. Read Appendix 2, Specimen Preparation and Identification (pp. 553–563).
REMEMBER: This is REQUIRED reading (and you will be examined on it).
Field Techniques used by the Missouri Botanical Garden
A Herbarium from Fun Science Gallery
"U Presum," Advice on Collecting Plants
The Value of Flattened Flora, from UC Davis Magazine (This is a particularly good article, so if you want to read just one of these articles, read this one!)
The price of collecting life, PDF from Nature
What Henslow taught Darwin, PDF from Nature (Shows the earliest-known herbarium specimen collected by Darwin!)
Using herbarium specimens to document global warming, PDF from American Journal of Botany
General Objectives:
After studying this material you should be able to:
- Know how to make a plant collection. Specifically, you should know how and what to collect, the type of data to be recorded at the time of collection, how to press and dry the specimen, and how to make a herbarium specimen complete with label.
- Know the various resources available enabling you to identify the specimens.
- Explain what a herbarium is, how and when it originated, and what is its function.
- Understand what a voucher specimen is and its importance in a scientific study.
- Know the size and location of the largest herbaria in the world and the US.
- Know how to properly handle herbarium specimens.
Making a Plant Collection
Equipment
- Be prepared
- Can be quite basic (e.g., a digging tool, pruning shears, plastic bags or a plant press, notebook)
Collection of Vascular Plants
Selecting the specimen
- Select the complete plant (if possible) or choose critical pieces
- The material collected should be representative of the population (be conscious of variation)
Collecting the specimen
- This is dependent upon habit and size of the plant (trees vs. herbs vs. succulents vs. aquatics)
- Collect critical material (flowers, fruits, underground structures)
Quantity of material to collect
- Enough to fill a herbarium sheet
- Depends upon purpose of collection (to document the presence of a species or to quantify amount of variation in a species or population)
Data to be recorded for adequate labeling
- A specimen is useless without supporting data. Be sure to include:
date of collection, distance and direction from nearest permanent landmark, state and county, habitat and associated species, odor, color, height, collection number. This information is necessary for adequate labeling of the herbarium specimen.
- It's not necessary to indicate the name of the plant, but you may wish to use some descriptor (such as compound umbel-bearing plant, damn yellow mustard, weird orange composite)
- Record all of this information in your notebook at the time of collection. Do not trust your memory!
Pressing and drying the specimen
Mounting specimens on herbarium paper
- The specimen is glued, taped and/or sewn down
- Leave some structure free for subsequent removal (if necessary)
- Preserve small or loose parts in a small envelope that is glued onto the herbarium sheet
- Attach a completed label
Preparing the label
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Click
here for examples of herbarium and annotation labels.
Plant Identification
Many sources are available to help identify your plant. Guides are available for edible plants, wild flowers, weeds, woody plants, and various ornamental and cultivated plants. References are also available for plants living in special habitats and for specific plant groups. Consultation with experts (e.g., taxonomists at herbaria, botanic gardens, universities, arboreta, and various state and federal agencies). Floras and manuals, however, are among the most widely used sources of taxonomic information.
Some Floras and Manuals appropriate for our region:
- Gleason, H. and A. Cronquist. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. New York Botanical Garden, Bronx, NY.
- Mohlenbrock, R.H. 1970-2000. The illustrated flora of Illinois. S. Illinois University Press, Carbondale, IL. 11 volumes published so far.
- Mohlenbrock, R.H. 1986. Guide to the vascular flora of Illinois. S. Illinois University Press, Carbondale, IL.
- Swink, F. 1990. The key to the vascular flora of northeastern United States and southeastern Canada. Plantsman's Publications, Flossmoor, IL.
- Swink, F. and G. Wilhelm. 1994. Plants of the Chicago Region, 4th edition. Indiana Academy of Science, Indianapolis, and The Morton Arboretum, Lisle, Illinois.
Pertinent Courses at UIUC:
World Wide Web:
See your textbook, pages 560-562, for a wealth of resources on the WWW.
International Field Guides, by Diane Schmidt from the University of Illinois Biology Library
The Herbarium
- 
Click here for another view of this herbarium
Definition and history
- A collection of dried plant specimens
- The collection can range in size from several specimens to millions
- The specimens are arranged in some system of classification (even alphabetically)
- The specimens are made available for systematic research
- They form the basis for most of our understanding of the pattern of variation in nature
- The concept began in the early 1500's, and the oldest extant specimens date back to 1532
- A herbarium was originally bound into volumes and dealt solely with medicinal plants
- By the time of Linnaeus, specimens were mounted on single sheets and herbaria were abundant
- By the mid-1800's there were several large herbaria in the US
Check out these nifty herbarium specimens:
- Darwin specimen This herbarium specimen, of the fern Asplenium magellanicum, was collected by Charles Darwin on the voyage of the H.M.S. Beagle. He collected this specimen in Chile in December 1834.
- Banks and Solander specimen This is a herbarium specimen of Solanum paniculatum, a member of the Solanaceae, collected by Banks and Solander, two botanists
that accompanied Captain Cook on his voyage around the world. This specimen was collected at Rio de Janeiro, Brazil in 1768
Why preserve plants? Functions of herbaria.
- Provides a standard reference for identifying plants
- Training of students. Complete specimens are available throughout the year
- Documents the presence of a species at a particular location and provides data on its geographic range. This may be the only record available for a species
- They document the morphological variability of populations, species and higher taxa, and their ecological characteristics, including blooming and fruiting times
- Provides samples of the flora of an area
- Highlights the existence of taxonomic problems
- Provides raw data for many different kinds of taxonomic and evolutionary studies. (DNA can be isolated from old, dried herbarium material, with permission of course!)
- Serves as a repository of voucher specimens documenting a study. A voucher specimen is a permanent record of the identity of a plant cited in a study. It also documents the presence of a species at a particular locality at a particular time.
Sizes of herbaria
The largest herbarium in the world is in Paris, France with over 9 million specimens. The largest herbarium in the US is found at the New York Botanical Garden with 7 million specimens. Considering all known 1,800 herbaria throughout the world, approximately 250,000,000 specimens are housed.
| LOCATION OF HERBARIUM |
NUMBER OF SPECIMENS |
| Museum of Natural History, Paris, France |
9,500,000 |
| Royal Botanic Gardens, Kew, England |
7,000,000 |
| Komarov Botanical Institute, St. Petersburg, Russia |
5,770,000 |
| Swedish Museum of Natural History, Stockholm, Sweden |
5,600,000 |
| New York Botanical Garden, Bronx, New York |
7,000,000 |
| British Museum of Natural History, London, England |
5,200,000 |
| Conservatory and Botanical Garden, Geneva, Switzerland |
6,000,000 |
| Harvard University, Cambridge, MA |
5,005,000 |
| Missouri Botanical Garden, St. Louis |
5,400,000 |
| US National Herbarium, Washington, DC. |
4,500,000 |
| University of Montpellier, France |
4,000,000 |
| The Field Museum, Chicago, Illinois |
2,600,000 |
Ethics of Plant Collecting
- Get permission to collect from the owners of private property
- Obtain the necessary permit(s) beforehand
- Collect the specimens away from areas frequented by the public
- Refrain from mass collecting (especially of rare plants). When in doubt, don't collect.
- Be aware of laws that restrict or regulate the collection of some plants
Procedures for Handling Herbarium Specimens
- Follow the instructions provided by the herbarium curator
- Do not bend sheets, and keep them flat and supported when carrying
- Keep food and drink away from all herbarium specimens
- Carefully remove folders containing specimens from herbarium shelves and cabinets
- Do not turn specimens like pages in a book but lift off each specimen individually
- Study the specimens on a flat surface using a long-armed microscope
- If specimens are cared for properly, they can last almost indefinitely.
So, you want to build your own herbarium?
Click here to get home!
