Using the Plant Press

Press a plant in the field or shortly after collecting as possible. Specimens are pressed in a plant press. This process involves alternating ventilators (corrugated cardboard), felt blotters and individual specimens carefully arranged and placed inside a newspaper. (See figure 5 below).

 

Organization of plant press
Organization of material in a plant press

  • The press is a rigid frame, usually made of wood.
  • The corrugated cardboard ventilators allow air circulation through the press.
  • The blotter paper absorbs moisture from the plant, and
  • the newspaper holds the plant material in place during the drying process. If the plant is not tagged, the collection number is written on this sheet of newspaper.

Arrange the plant so that it will fit on a standard herbarium sheet (11.5" x 16.5"). It is difficult to rearrange the specimen after it is dry and stiff.

Arrange the plant so that all all parts necessary for identification will be visible after it dries and is glued to the sheet. The plant should look semi-natural, but it is best to be able to see the abaxial sides of some leaves, the adaxial sides of others, different views of flowers, etc.

Placing plants in the press is like building a layered sandwich:

  1. carboard ventilator,
  2. blotter,
  3. folded newspaper containing plant,
  4. 2nd blotter and 2nd ventilator on top of the plant-containing newspaper.

Stack remaining plants in this manner and place the stack between the two frames. The plant press is tightened using straps or cords. The objective is to extract moisture in the shortest period of time, and to yield material that can be mounted on herbarium paper for storage in an herbarium.

Pressing without a press

Pressing flowers has been a hobby for a long time, and it can work well. You just need a big book, something absorbant (like paper towels), and the plant.

Hobby pressing

The main thing missing here is ventilation. Moisture will move from the plant into the paper towel, but it cannot leave the book rapidly. You can remove moisture by repeatedly changing the outer layers of paper toweling (not the inner one that encloses the plant).