The Plant Press

From The Plant Press, Vol. 26, No. 4, October 2023.

A guide to collecting plant specimens for the US National Herbarium

By Jillian Vallance

A specimen is a single plant that can be used as an example of a particular species to be examined by scientists, historians, and artists. Botanists collect specimens to assist in current research, aid in future research, or fill in a botanical blackhole. A botanical blackhole is when there is a location that is largely undocumented or unstudied. 

Scientists are not the only ones who can collect specimens. Citizen scientists describe anyone collecting specimens in a non-professional capacity. They may collect to fill a gap in the botanic record, aid in research that is being conducted by a scientist, or for their own personal collection!

Citizen science is a great way to increase scientific knowledge and engage more of the public in the scientific community. If a citizen scientist has a collection of flora and they have received approval from the Department of Botany’s collection manager, they are welcome to send their specimens to the Smithsonian to be mounted and added in the US National Herbarium. For the specimens to be accepted by the museum, the collector must have permission from the landowner to collect, must supply copies of permits, and must provide a formal signed and dated Deed of Gift. The plant should not be on any threatened, endangered, or rare list. Plant apps, such as SEEK and iNaturalist, can be used to obtain an identification in the field.

Please keep in mind the Smithsonian’s botanical collection is exceptionally large and sending in a specimen does not guarantee it will be used for research immediately. 

Specimen collection: good practices

Materials needed (Fig. 1): 

• Pen
• Field notebook or paper
• Hand pruners or clippers
• Newspaper
• Plant press. Learn how to make your own here

Step 1. Record the collection: Once you find the plant you intend to collect, record your name, the date, anyone who accompanies you and a description of the plant (height, flower color, etc.), and specific details on the location in your field notebook. The description of the location needs to be detailed enough for someone to find it in the future; add any roads that may be nearby or special landmarks. If possible, identify the family, genus, and species of the sample collected. If multiple plants are being collected, it is helpful to assign each intended specimen with a field number in your notes (Fig. 2). 

Step 2. Specimen collection: Identify which portion of the plant would make the best specimen; you are looking for parts that express a variety of features of the plant. These parts include fruits, flowers, leaves, and root systems. Multiple collections may be required for a well-rounded specimen. Unless the plant occurs in great abundance in the area you are collecting, avoid cutting off portions of the plant that may affect the future health of the plant (Fig. 3). 

Step 3. Arrange and press: Clip your selected portion and arrange it between sheets of newspaper to feature the most diagnostic parts of the plant. The sample should fit on an herbarium sheet, which is 11.5 inches x 16.5 inches. Use the plant press to secure the sheets of newspaper between layers of cardboard, flatten the plant, and write the plant’s assigned field number on the newspaper. Once the collection is complete, place the plant press somewhere warm and dry, like a car. The plants will need a few days in the press to dry (Fig. 4).

Step 4. Label and mount: If you are planning to mount the specimen—or send it to the Smithsonian to be mounted—construct a label consisting of all the information about the plant recorded in your field notes. The label needs to be included with your specimen if you send it to the Smithsonian (Fig. 5). 

For a personal collection, the plants can be mounted in any way the collector prefers. The Smithsonian mounting process uses specific protocols and archival materials to ensure the longevity of the specimen, which is why any specimens sent to the museum should be unmounted (Fig. 6).

Preparing specimens for the Smithsonian – a checklist:

• Identify an area that is either largely undocumented or botanically significant.
• Contact the Department of Botany’s collection manager <USNH@si.edu> for permission to send specimens and to prepare the appropriate paperwork. 
• Before collecting, verify the plant is not on any threatened, endangered, or rare list.
• Use best practices when collecting specimens of flora. 
  • Get permission from the landowner to collect and keep copies of all applicable permits.
  • In a field notebook, record the collector(s) name, date, field location, and detailed plant description. Include coordinates, elevation, and accurate family identification, if possible. 
  • Press the plant to feature as many aspects of the plant as possible. All components of the specimen will need to fit on a 11.5" x 16.5" herbarium sheet.
  • Let the sample dry inside the plant press for a couple of days, and ensure the press is kept dry and warm. 
• Make a label to match each sample, this label should include:
  • Initial field identification to family, genus, or species, if possible.
  • Collector’s name and whoever accompanied them. 
  • Collection date.
  • Specific location of where the sample was collected, including coordinates and elevation, if possible.
  • Specimen description. 
  • Field number if multiple specimens are collected to match the label to the sample. 
• Specimens are ready to be sent to the Smithsonian only if the following are included:
  • Unmounted, completely dried specimens still in newspaper. If multiple specimens are included there needs to be an indication of assigned field number.
  • Completed labels for each sample.
  • Appropriate permits.
  • Deed of gift to the Smithsonian.
  • Itemized list of specimens sent for donation.