Specimens on the substrate should be thoroughly dried before mailing; usually air-drying is sufficient. Large fleshy fungi may require the use of a dehydrator. Characteristics that will disappear upon drying, such as the color of fleshy fungi, should be noted and included with the specimens.
Fungi on leaves or other thin substrates should be pressed in a plant press or simply under a heavy weight.
Fungi on woody substrates or twigs should be trimmed to about 12 x 10 cm, dried, and placed in a paper bag or similar container.
Herbarium packets can be used to contain specimens on twigs, bark or leaves. Packets can be made from simple materials such as a sheet of white paper with or without cotton wadding to preserve delicate structures.
100% cotton, acid-free paper is best for making herbarium packets for long term storage.