Herbarium

What is a 'herbarium'?

"A herbarium is defined as a collection of plants and their parts that have been dried, pressed, and preserved on a sheet of paper and arranged according to any accepted system of classification for future reference and study."

Herbarium preparation
A standard herbarium (available at Herbarium of the Department of Botany, KNIPSS, Sultanpur)

Method of preparation of herbarium specimens

Following steps are there to prepare a herbarium:
  1. Field visits
  2. Collection of specimens
  3. Pressing and drying
  4. Mounting on a herbarium sheet
  5. Labeling
  6. Preservation and storage (maintenance)

1. Field visits

A complete plant specimen in all senses carries roots, shoots, flowers, and fruits. In most of the plants, flowering is seasonal and varies from plant to plant. Therefore, regular field visits round the year (at least three seasons) are necessary to obtain information at every stage of growth and reproduction of plant species.


2. Collection of specimens

The person who collects the plant materials is the 'collector'. A collector should carry following tools while going for collection.
  • Plant cutter (pruning secateurs): for cutting the twigs.
  • Trowel (digger): for digging out herbaceous roots.
  • A long stick with hook (sickle): for collecting parts of tall tree.
  • A field note book: for recording the necessary information in in-field.
  • Old news paper: for protecting the collected materials.
  • A vasculum (specimen box): for transportation of collected material without damage or wilting.

3. Pressing and drying

The collected specimens are spread out between the folds of a blotting sheet or absorbent newspaper. The larger specimens should be folded in 'N' or 'W' shape. These are stalked upon each other by placing some more blotting sheets or absorbent newspaper in between and placed in the plant press for drying. Pressing may be done in a wingnut plant press or plyboard tightened with two straps. The plant press should be kept in proper aerated places.

4. Mounting on a herbarium sheet

Well-dried plant specimens are fixed on a herbarium sheet. A herbarium must be of standard size, i.e., 41 × 29 cm. Specimen is mounted on herbarium sheet with the help of thread, adhesive, glue, or tape.
Seeds and other bulky materials are kept in a small envelope and attached to the lower-left corner of the sheet as 'fragment packets'.

5. Labeling

A label should carry information about the common name, scientific name, locality, habit, habitat, etc. The label may be printed or pasted on the lower right corner of the herbarium sheet.

6. Preservation and storage (maintenance)

The mounted specimens are sprayed with fungicides. 2 % solution of mercuric chloride (HgCl2) well servers the purpose. The prepared herbarium specimens are placed in the cupboards at their proper position according to any accepted system of classification. In most of the renowned herbaria of the world Bentham and Hooker’s system of classification is used.

Virtual herbarium

It is a database of dried plants (herbarium) that maximizes the usefulness of the collections by making them available on World Wide Web (www).
Example: Indian Virtual Herbarium of the Botanical Survey of India available at: https://ivh.bsi.gov.in/. It has 4,701 Specimens of Cryptogames and 1,00,228 Specimens of Phanarogames.


First published on 24-09-2024
Last updated on 24-09-2024