A flora of Manila - Rainforestation

PREPARATION OF SPECIMENS 23
the specimens are arranged or the stack gets too high for convenience, the
whole should be placed under pressure, usually from 20 to 30 kilos being
sufficient.
The most convenient method of applying pressure is by means of a
press which is best made of split bamboo, either nailed together or fastened
by rattan, wire, or string; the cross-slats should not be more than 3 or
4 cm apart. The press frames should be a little larger than the sheets
used for driers, a convenient size being 50 by 35 cm. Pressure can be
applied by straps, or better by means of stout cords attached to each
corner of the lower frame, to be fastened to the corners of the upper
frame as pressure is applied. Presses are not essential as pressure can
be applied by other means. The driers with specimens to be dried can
be stacked in piles up to 60 cm or so in height, and a board placed on the
stack, pressure being applied by means of stones or other weights.
Presses containing drying plants should, so far as possible, be kept in
the sun in a breezy place during the day but should be placed under cover
at night and in damp or rainy weather; during the rainy season, or during
protracted rains they should be placed near or over a fire.
As a rule the oftener the driers are changed, the better, and this
should be done at least once each day, otherwise the specimens are apt to
discolor badly, become mouldy, or even decay. In changing driers remove
the specimen sheet with the enclosed plant or plants to fresh driers
ivithout disturbing the drying plant itself. The damp papers (driers)
should be thoroughly dried befoi'e using again, either by spreading them
in a sunny place or drying them by fire. Better results will be secured
by replacing the damp driers with warm or hot dry ones.
Extra flowers, and especially very delicate ones should be placed in
packets of thin paper in drying, and parts that become detached in drying
such as flowers, fruits, etc., should also be so treated.
The length of time necessary properly to dry specimens varies very
greatly, some species such as slender grasses and sedges, most ferns, etc.,
drying well in from one to three or four days according to the number of
times the driers are changed, and whether or not artificial heat is used, etc.
Other species are more slow in drying, and some succulent plants, like most
orchids, dry very slowly. In such cases it is advisable first to kill the
plant by plunging it in boiling water for a moment, being careful, however
not to immerse the flowers; the plant thus killed will dry much quicker
than if not so treated.
When the specimens are thoroughly dried they can be removed from the
press and" stored in well wrapped bundles until desired for study or for
other purposes. To protect the dried specimens against the depredations
of small insects it is almost essential in this country that a small amount
of naphthalin or some similar repellant be sprinkled over the specimens.
Notes on specimens to be preserved should be as full as circumstances
permit. To be complete they should show the locality, habitat, altitude,
date of collection and collector, size of the plant, if not shown by the
specimen itself, habit of growth, color of the flowers and its parts, odor
if any, color and any particular characters of the fruit that would be
destroyed in drying, local name, economic uses; in short all data that are
not shown by the dried specimen itself. The label bearing these data should
be attached to the specimen or preserved with it.