Systematic Biology (Plants) Lecture Notes

Course Information

Lecture: 60%
Term/Final Exams: 30%
Quizzes: 20%
Journal Critique/Projects/Assignments: 10%

Plant Collection and Specimen Preparation

Fundamental aspects of study, training, and research in plant systematics.
Herbarium specimens are permanent records of plant species from a particular place at a given time.

Plant Collection Guidelines

Collect entire, vigorously growing typical specimens.
Avoid collecting insect-damaged specimens.
Collect underground parts (bulbs, rhizomes, tubers) of herbaceous perennials.
Collect specimens that contain flowers, fruits, and seeds.
For grasses, herbs, and other small annuals, collect the whole plant, including rhizomes, tubers, and other underground fleshy parts.
For trees and shrubs, obtain mature healthy branches with leaves, flowers, and fruits intact.
Collect three to four samples per plant/plant colony.
Assign a collection number for each plant.
Record information about the plant (locality, habitat, description, etc.) in a field notebook.
Specimens larger than a single sheet should be divided and pressed on a series of sheets.
Collect plants with leaves intact, as different kinds of foliage prove helpful in identification.
Collect bark and wood samples of woody plants.
The best time to collect plant samples is during the afternoon, except when the weather is rainy.
Put the tagged specimens in separate plastic bags, then drain them in alcohol before pressing.
Never collect the only plant of a species in a locality.

Field Equipment and Supplies

Field Press: A pair of hardwood, metal, or strong plywood frames of 12 by 18 inches.
Driers or Blotters: Heavy blotting papers or moisture-absorbing materials of 11 by 16 inches.
Straps or Ropes: A pair of strong web straps of about 4-5 feet in length used to tighten the press.
Corrugate Ventilators: Sheets of corrugated cardboard of 12 by 18 inches used in between the driers to provide space for air passage and moisture removal.
Field Notebook: Used to record the date, place, locality, habitat, elevation, local name, and collector number of the collected plants.
Digging and Clipping Tools: Trowel, digger, hammer, pruning shears, garden clippers, geological pick, and heavy sheath knife.
String Tags: Waterproof material used for labeling plants that are not immediately pressed.
Vasculum: A container made of tin or aluminum sheet with a hinged light lid to preserve the plant’s freshness for some time.
Collecting Bags: Plastic bags used as containers for fresh specimens.
Collection Bottles: Glass or plastic bottles with leakproof screw caps used for collecting small-sized material to be preserved in liquid preservatives.
Liquid Preservatives:
- Formalin-acetic acid-alcohol (FAA) – common for anatomy materials.
- Chloroform—95% ethyl alcohol & glacial acetic acid: 6:3:1 – used for cytology materials.
Hand Lens: A 5x or 10x lens.
Waxed Paper: Used for pressing viscid or weak-looking plants.
Cardboard Storage Boxes: Used to store dry materials.
Maps: For determining the localities for particular species.
Color Charts: Used in determining the actual color of the parts (flower, leaves) in the field itself.
Camera: For taking photographs in the field.
Others: Compass, thermometer, seed envelopes, insect repellent, psychrometer.

Organization of the Field Press

Hardwood or plywood press
Corrugate ventilator
Drier or blotter
10 sheets of torn newspapers (each sheet will contain one specimen)
Drier or blotter
Corrugate ventilator
Repeat steps 3-6 until 100 specimens (10 groups of 10 newspapers) are included
Hardwood or plywood press

How to Press Plant Specimens

Specimens should be pressed as soon as possible.
Specimens should be placed carefully on a pressing sheet.
Extra leaves or branches are removed if necessary.
Plants too large may be bent into a V, N, or M figure. Specimens should not protrude from the fold of the paper.
Some upper and lower surfaces of leaves must be exposed.
Flowers or inflorescence should be spread out thoroughly.
A few flowers can be cut longitudinally and pressed, if possible.
Each sheet should contain a collector’s number which refers to the notes in the field notebook.
The specimens in the specimen paper are placed in between driers or blotters.
All the specimens are placed for pressing in such a way that the entire bundle is ultimately of almost uniform thickness in the middle and sideways.
The press should be tightly bound with ropes or straps to prevent wrinkling of specimens.

Drying of Specimens

Specimens should be dried as rapidly as possible.
The press containing the specimens is placed in the sun.
After 24 hours, the press is opened, and the specimens are placed in fresh blotters.
Any large rearrangement of the plant parts may be made at this time.
The press along with the specimens in fresh blotters is now again bound tightly.
The wet blotters are dried in the sun for reuse.
For 3-4 days, the wet blotters or driers are changed daily until the specimens are completely dried.
The press becomes loose when the plants are completely dried.
Artificial heat may also be used for the drying process.
Never to be dried in an oven.
In humid regions or rainy season, the plants may be dried in a drier.

Drier

Made in the form of a wooden box (3 ft in length and 18 inches in breadth made up of 1/10 inch thick boards).
Five light bulbs of 60 watts are fitted inside for producing heat.
Small openings are made at the bottom of the box for the entry of air which gets heated and will dry the plants.
A press containing 100 specimens can be dried in 8-12 hours.

Mounting of Specimens

The process by which a dry specimen is attached to a mounting paper or a herbarium sheet, and a label is affixed at the lower right corner of the sheet.
Herbarium sheet size: 28.75 by 41.25 cm (11.5 x 16.5 inch).
Before mounting, dip the dry specimens in a saturated solution of mercuric chloride in ethyl alcohol to prevent infection of fungi, insects, etc.

Poisoning

12.15 grams mercuric chloride
5.10 grams of phenol crystal
1. 0 liter of denatured alcohol
(CAUTION: HIGHLY CORROSIVE AND POISONOUS CHEMICALS)
Use only denatured alcohol
Use lauryl pentachlorophenate

Mounting of Specimens

A good quality glue or paste is applied to the back of the specimens (Elmer’s glue).
Loose parts (seeds, fruits) and dissected parts are placed in a paper packet and pasted on the same herbarium sheet.

Labeling of Specimens

Label size: 6.5 X 10. 5 cm
Pasted on the lower right side of a herbarium sheet
High rag quality

Labeling Information

A. Heading – institution
B. Family name
C. Local or vernacular name
D. Scientific name – genus, species along with authority
E. Locality – place of collection
F. Habitat – vegetation type
G. Collector
H. Determined by – the one who authenticated the identification
I. Collection number – starting with 1 and continuing throughout the lifetime of the collector
J. Additional Information (color of leaves & flowers, associated plants, economic uses etc.)

Labels

FIELD LABEL and HERBARIUM LABEL
FIELD LABEL – upper left hand corner
HERBARIUM LABEL – lower right hand corner

Label Information (Cont.)

FIELD LABEL – common/vernacular name; scientific name; date; locality; habitat; important plant notes
HERBARIUM LABEL – herbarium no., family name, scientific name, collector, determined by, collector number

Fluid Preservation

Fleshy fruits, large flowers, and other botanical specimens are stored in fluid preservation.
The specimen (whole or sliced) is simply immersed in liquid preservative contained in a properly labeled bottle.

Liquid Preservatives

FAA1 (formalin aceto-alcohol) – 50 parts 95% ethyl alcohol + 40 parts distilled water + 5 parts glacial acetic acid + 5 parts 38% formalin
- Ex. 500 ml 95% ethyl alcohol + 400 ml distilled water + 50 ml. glacial acetic acid + 50 ml 38% formalin
FAA2 – 90 parts 70% ethyl alcohol + 5 parts 38% formalin + 5 parts glacial acetic acid
- Ex. 900 ml 70% ethyl alcohol + 50 ml 38% formalin + 50 ml glacial acetic acid