School of Sciences, Lautoka Campus
BIO509 Botany Lecture 37: Herbaria and
Plant preservation
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Herbaria
• Libraries of dried, pressed (and/or
liquid-preserved) plants, algae, and
fungi, arranged and labeled so that
specific specimens can easily be
retrieved.
• Some have millions of specimens.
• Specimens are stored in airtight
cabinets.
• Collections must be kept bug free.
Methods of Preparing Herbarium Specimens
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Materials for pressing:
Hardwood plant press.
Strong straps (2).
Cardboards (or aluminum
corrugates).
• Old newspapers.
• Blotters.
• A representative sample
(with stem and leaves,
flowers and fruits) is
selected to fit on the
newspaper.
• The specimen is put into
the newspaper, arranged
to show both leaf surfaces.
• If the plant is too big, use
a representative sample.
• One specimen per newspaper,
one number per species.
• A field number (your own
numbering system) is written in
pencil on the outside of the
page.
• Keep notes in a field book about
location, habit, color of fruit or
flower, habitat, date and the
specific number.
• It is helpful to keep specimen
records in a record book.
• Cardboards and blotters are
added.
• The press is tightened to
compress the specimens.
• The press is put into a drier
(the sun does not work in the
tropics).
• The press is checked daily and
tightened as needed.
• Drying may take one to
several days.
• Use herbarium paper, which has a high rag content,
for long life.
• The paper should be 29 x 42 cm.
• Water soluble glue is usual, but some people use
plastic glue.
• Put specimen into glue on
a glass and transfer it to
the paper.
• Or, put specimen on the
paper and strap down
with gummed strips or
globs of blue, with
weights to hold it in place
until it is dry.
• Leave the bottom right hand
corner free with enough space
to put a label approximately
8 x 13 cm in size.
• Add a label, with typed information, including family,
scientific name, location, date, collector, and date.
• Storage of Herbarium Specimens.
• Specimen is then best put into a
plain newsprint folder.
• These are stored in manila
folders, arranged in alphabetical
order in the genus, in the family.
• The families are put into
alphabetical or taxonomic order.
Questions??