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Activity: The Botanical Survey
Collecting plant specimens is a key component of any ethnobotanical research project. It provides both a frame of reference for understanding and analyzing indigenous knowledge of plants. Properly collected specimens
are essential for obtaining taxonomic identification. In addition, these specimens provide a permanent record of information that can be reviewed or assessed. Herbarium specimens are the main tools for taxonomic
identification and in most cases determinations are only as good as the specimens on which they are based. Collecting sterile (lacking flowers or fruits), insufficiently annotated, or poor quality specimens is a
waste of time and space any may result in incomplete or unreliable determinations.
The Herbarium Specimen
A good herbarium specimen consists of a dried, pressed section of a plant containing well-preserved vegetative and reproductive (flowers, fruits) structures. Plant specimens are
mounted for permanent storage on sheets of standard bond paper measuring 11 1/2 and 16 1/2 in. In the bottom right hand corner of the sheet there is a label containing information on the plant, a description of its
appearance, and the area where it was collected. A small paper pouch attached to the herbarium sheet is used to keep small pieces of the specimen that might have become dislodged with time as well as extra flowers
or fruits purposely collected. Herbarium sheets may also include photographs of the live plant or its parts, maps of the collection area, and hand-written annotations by taxonomists.
Collecting Specimens
Tools and Equipment;
Pruning Shears Pocket hand lens (10X)
Trowel Masking and Duct Tape
Collection notebook Plastic Waterproof Jars
Paper tags Measuring tape
Pencil or waterproof pen Camera (optional)
Newspaper
Large, heavy-duty plastic bags
Sealable plastic, cotton and brown paper bags First-aid kit
Procedure:
1. The sample chosen for pressing should be representative of the size, variation and general appearance of the plant or population being studied. Usually three sets are needed. One class
set for reference, one set for the student and one for the library. Whenever possible, the whole plant should be collected and pressed in between the pages of newspaper. Before pressing herbaceous plants, shake the
roots or wash them to remove any mud or sand. Please note that collecting plants in national state parks is illegal, some states have various laws on plant collecting, check with your local authorities.
2. Each specimen should be labeled with masking tape or a paper tag with its respective collection number. All samples of the same collection should be carefully bundled and gently pushed
to the bottom of a collecting bag. Delicate plants or plant parts, as well as loose material should be placed separately in labeled bags. Plants collected in a plastic bag should be pressed as soon as possible.
3. Field notes should include the following information:
Have the students draw the plant as it appears in nature focusing on the above mentioned characteristics.
4. Correctly arranging the specimen in the newspaper is very important; dry specimens are brittle, and their parts cannot be arranged without breaking off. Place the specimen over the
newspaper and cut excess length or fold the stem to insure a portion of the base is intact. Both surfaces of the leaves and reproductive structures should be visible, so at least one leaf and one flower should be
turned over. Some flowers should be pressed open, some closed. If possible, one flower should be dissected to show internal structures.
5. Do not leave any plant part projecting out of the newspaper; these will break off when dry. Parts that may not stay flat can be held in place by strips of newspaper that is taped to
the paper and not the plant.
6. Plants kept too long before drying may mold and the leaves abscise. It is possible to dry small numbers of specimens by leaving them in the sun encased in newspaper, replacing moist
paper with dry ones each day. Placing the specimens underneath books helps to flatten the specimen and speed drying.
7. The finished product will consist of the pressed plant properly mounted (this may be done by gluing the plant directly to the paper with Elmers Glue). It is not necessary to use 111/2
by 161/2 paper, standard 111/2 by 81/2 in. will do just as well. Good quality black and white or color photographs may be included on the same page.
8. The label is placed in the lower right hand corner of the page with the following information:
- The project title
- Genus, species
- Family
- Locality
- Habitat
- Collector
- Date of collection
9. Placing the mounted specimens inside a plastic sleeve and taped shut may preserve the herbarium. An alternate method may be to use a photo album with magnetic pages.
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