1. LAB 2
Collection and Preservation of Plant materials and Herbarium preparation

2. Plant Collecting and Documentation
Collections:
Samples of plants
Dried or liquid preserved.
Kept alive, grown in greenhouse or garden

3. ѴPreservation is of types:
1. Dry Preservation/Herbarium: A collection of dried plant specimen mounted on sheet is known as Herbarium.
2. Wet Preservation: Very fleshy and delicate structures, including small algae are best preserved in air tight Glass jars with liquid preservatives.

4. Wet preservation:

5. Ѵ Why collect?
Provide resource material for plant systematics studies.
Serve as a reference collection for named taxa, known as a voucher specimen.
a) Type specimen in formal naming
b) Reference for the identity of a taxon
-in systematic studies
-in field studies, e.g., floristic surveys
3) Provide information about the plant in a native habitat: put info. in database

6. Ѵ Should you collect? What to collect?
Generally DON’T collect “listed” taxa: rare, endangered, or threatened
Must know ahead of time which these are!
When you collect, use “1 to 20” rule:
– For every herb you collect, make sure there are at least 20 in the population.
– For every branch of a shrub or tree, make sure there are at least 20 more.

7. How to collect?
Herbs: Must dig up at least one entire plant to show root or rootstock (e.g., corm, bulb, rhizome)
Shrubs, trees, vines: One branch sufficient.
Collect a representative specimen that shows vegetative and reproductive parts (in flower, fruit, cone, with sporangia, etc.)

9. Plant Press Cardboards: ca. 12” x 18” Newspaper, ca. 11.5” x 16.5”
Tighten straps
Place in plant drier, 2-3 days
Remove and check if dry (if it feels cool, not dry)

10. Liquid-Preserved Collections
Anatomy, embryology, palynology, etc.: FAA (Formalin - Acetic Acid - Alcohol (ethanol)
Cytology (chromosome numbers): Carnoy’s (100% ethanol : glacial acetic acid)
Living Collections :
Grow in greenhouse or botanic garden
Valuable for long-term studies

11. Ѵ How to make a Herbarium?
1) Collecting the plants
2) Pressing and Drying
3) Mounting

12. 1) Collecting the plants
Choose good representatives of the plants species
Be careful that these plants must include root, stem, flower and fruit
Take notes and record by taking photos in the field at the time of collection,
Note these factors below:
“Date, collection number, location, habitat, habit, special characteristics”

13. 1) Collecting the plants
Choose good representatives of the plants species
Be careful that these plants must include root, stem, flower and fruit
Take notes and record by taking photos in the field at the time of collection,
Note these factors below:
“Date, collection number, location, habitat, habit, special characteristics”

14. Collect specimens in dry conditions, a good time being mid-morning, after the dew has dried but before the heat of the day causes plants to wilt.
If specimens are at all wet or you need to wash soil off the roots then dry them carefully before pressing.
Use a pencil for these notes rather than a pen because any damp/wetness can cause ink to smudge and be unreadable

15. Materials for plant collecting:
Plant press
Plastic bags or nylon bag
Garden secateurs & trowel
Small note book & pencil
Jeweller’s tags (optional)
Camera (optional)
GPS & altimeter (optional)

16. PRESSING AND DRYING

17. PRESSING & DRYING - Plants must be clean before pressing
They must also be put in a plastic bag or nylon bag, if it is hot they must be watered to be fresh
Place your plant between folded-out sheets of newspaper, although flimsy or greaseproof paper is preferable for delicate material
Arrange the plant carefully, trying to avoid overlapping.
When you have finished arranging the specimens within the newspaper sheets (or whatever combination of papers you have chosen), you then need to intersperse them between corrugated card sheets to aid ventilation.
Finally place everything in your press and tighten well.

18. For the first two to four days you will need to check daily and change the blotting paper and/or other surrounding papers, and retighten the press, but as the plants dry these checks can become less frequent.
Warmth may be used to improve the drying rate, An oven set at 50°C may be used but the heat must be no higher, otherwise the specimen will become very brittle and damaged.

19. Pressing:

20. Pasting:

21. MOUNTING Cartridge paper for mounting your specimens should preferably
be A3 size and acid-free; the
weight should be a minimum
180g/m2, and ideally with a rough
textured surface
Using only one side of your thick A3 cartridge paper, arrange your specimens carefully, making sure that they represent the way the plant grows naturally

22. Example Herbarium Label
Scientific name: Ranunulaceae, Ranunculus ficaria (family, genus and species)
Vernacular name(s):  Lesser Celandine, Pilewort
Collector’s name and specimen number: Lawrence 1
Date of collection:  20th March 2003
Locality:  Orleans House Gardens, Twickenham, England
Habitat: damp, clay soil, 20 yards from riverbank, growing in dappled shade on the edge of deciduous woodland; nearby plant is Dock (Rumex obtusifolius).
Habit: perennial herb, up to 20 cm tall, with stems creeping and rooting
Characteristics: leaves hairless glossy green, flowers bright glossy yellow, turning white with age

23. Herbarium sheet:

24. Herbarium card

25. Exercise 2
Prepare 2 herbarium sheet with their description.