Mounting Specimens on Herbarium Sheets

Mounting is the process of affixing a dried pressed plant and its label to a sheet of heavy paper. This allows the specimen to be handled and stored with minimum damage.

Supplies Needed:

  • Dried, pressed plant specimen WITH label.
  • Glue: There are special glue products for herbarium specimens. We often use white Elmer's glue. It should be a consistency of heavy cream.
  • Mounting paper. The weight of the paper used in herbaria varies, but it is always acid-free. Size, 11 ½ x 16 ½
  • Smooth surface like a thick piece of glass, plastic, cookie sheet about 18" square.
  • Paint brush(s), small glass dish to hold glue or a squeeze bottle for applying glue; weights
  • corrugated cardboard or foam, wax paper (all size of herbarium mounting paper).
  • fragment packets, tweezers, paper towels or sponges.

Gluing the Plant Specimen:

Arrange the plant and label on the mounting paper before gluing anything down. Labels are placed in the bottom right corner.  

Gluing Steps:

  1. Gather and arrange the supplies (listed above) on a roomy clean table or similar surface.

  2. Paint a smooth, light coat of glue on the entire back side of the label. Affix the label in the bottom right corner, smooth it down.

  3. Apply glue to the specimen.

    Each plant will need a different amount of glue. Put more glue along the stems, less glue on the leaves and the least glue on the flower and fruiting parts. There are two methods for applying glue to the plant depending on how delicate or how robust the plant specimen is. Often the decision is to use a combination of both. The general rule is use glue sparingly to attach the plant. Too much glue may obscure the flowers and fruits after drying and make identifying characters difficult to see.

    Method 1: For many plants, place about 2 tbsp glue in the center of the piece of glass. Spread to an even, thin layer of glue with the brush.

    Carefully place the plant or part of the plant on to the glue and gently press the stem, leaves, peduncle and/or flower receptacle in to the glue. Remove the plant by slowly pulling it toward you while lifting at the same time.

    Turn over the plant and inspect it to make sure the specimen has a sufficient amount of glue. Sponge away excessive glue or, if not enough glue, use the brush or squeeze bottle to apply where needed, especially on stems.

    Place the plant on the herbarium sheet the way you had previously arranged it.

    Method 2: Some plants are too delicate or have too much material for the method above to work. In that case, hold the side to be glued face up and brush or squeeze glue on to the specimen, turn over and place on herbarium sheet.

  4. If there is a fragment packet, affix that in a similar way as the label.

  5. With a damp sponge, gently wipe up any stray drops of glue.

  6. Apply gentle pressure to the specimen while the glue dries. There are two ways of doing this. If you are gluing only a few samples, you can just put small weights on the sample to press the glued surface to the paper. If you are mounting multiple specimens, you may need to stack specimens as they dry. If that is the case, form stacks of items in the following order (from bottom up): cardboard, mounted specimen, wax paper, foam, another cardboard, another mounted specimen, etc. The wax paper is used to prevent the wet glue from sticking to the foam and cardboard. In a few cases, if the stem(s) are heavy, a few weights can be placed on the wax paper before stacking another plant on top.

The glue dries in 8 hours or less (overnight). Remove the specimens from the stack. They are now ready for storage.

 

Web Pages

University of Florida Herbarium Specimen Preparation Guide: https://www.floridamuseum.ufl.edu/herbarium/methods/mountingguide.htm

Preparation of Plant Specimens for Deposit as Herbarium Vouchers: https://www.floridamuseum.ufl.edu/herbarium/voucher.htm