page_title: Plant press
section_title: Construction
hierarchical_section_title: Plant press / Construction
caption_attribution_description: Drying herbarium specimens with a gas cooker and a wooden construction. Design of the Herbier de l'Université de Ouagadougou, Burkina Faso
context_page_description: A plant press is a set of equipment used by botanists to flatten and dry field samples so that they can be easily stored. A professional plant press is made to the standard maximum size for biological specimens to be filed in a particular herbarium. A flower press is a similar device of no standard size that is used to make flat dried flowers for pressed flower craft.
  Specimens prepared in a plant press are later glued to archival-quality card stock with their labels, and are filed in a herbarium. Labels are made with archival ink and paper, and attached with archival-quality glue.
context_section_description: A modern plant press consists of two strong outer boards with straps that can be tightened around them to exert pressure. Between the boards, fresh plant samples are placed, carefully labelled, between layers of paper. Further layers of absorbent paper and corrugated cardboard are usually added to help to dry the samples as quickly as possible, which prevents decay and improves colour retention. Layers of a sponge material can be used in order to prevent squashing parts of the specimens, such as fruit. Older plant presses and some modern flower presses have screws to supply the pressure, which often limits the thickness of the stack of samples that can be put into one press.
caption: Filled plant presses arranged on a gas-fired heater, with air circulation upwards through the layers
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