Visitor Info

We welcome all Penn State faculty, staff, and students as well as the interested public to check out the PAC Herbarium

Hours of Operation

We are open the following days during the Academic Year:

  • Monday, Wednesday and Friday: 9:30 am – 5:30 pm
  • Tuesday and Thursday: by appointment

It is advised that you call or email before your visit to ensure that someone is here. Appointments to visit at other times may be made by contacting Curator Sarah Chamberlain.

Phone: 814.865.6201

How to Find Us

The PAC is located in 10 Whitmore Lab on the Penn State University Park campus. Whitmore is the next building south of Mueller Lab. To enter Whitmore, there are a number of doors, but as PAC is in the NE corner of the basement, the north entrance directly across from Mueller is the best. Go down the stairs to the basement and turn left to Room 10. Between the doors at the bottom of the herbarium stairs and Room 10 is the men’s restroom. The women’s restroom is immediately to the right as one goes through the doors at the bottom of the stairs. Handicapped persons can reach the herbarium by using the main entrance on the west side of the building. There is an elevator on the first (ground floor) at the very end of the hallway. Go down to the basement level and proceed to the extreme other end of the basement to Room 10.

The PAC has an air-conditioning system that keeps the temperature at 69 degrees F with low humidity. This has the purpose of retarding mold and insect depredation. Users are advised to bring a sweater – especially in the warm weather months when light-clothing is the norm.

Organization of the Herbarium

General Organization

Seed plants in PAC are arranged more or less according to the family system of Engler and Prantl which gives each plant family a number. Staff can assist you in locating the appropriate number(s) for the plants you’d like to view. Pteridophytes (ferns, lycopods, etc.) have a separate numbering system for families, but the color-based system for folders, etc., is the same as for spermatophytes (seed plants). Bryophytes (mostly mosses and liverworts) are arranged by family according to a recently published numerical system. They will be found, along with algae and lichens, in a case near the entrance to the herbarium. The family numbers for bryophytes are in a notebook on the main work table at the rear of the herbarium.

Geographic Areas

All vascular plants (seed plants and pteridophytes) are organized as follows:

  1. Plants from Pennsylvania: in buff (“manila”) folders. Plants are filed alphabetically by genus, then alphabetically by species. Within a species, the plants are filed alphabetically by county, Adams County first, York County at the end
  2. Plants from North America, north of the Rio Grande, except for PA, are in red folders, organized alphabetically by genus first, then by species. Within a species Canada plants are first, filed alphabetically by province, then USA plants, alphabetically by state
  3. Plants from Eurasia, Indonesia area, Australasia area, Oceanic Islands, etc. are filed in orange folders, alphabetically by genus, then by species, and within a species, alphabetically by country
  4. Plants from Latin America, North America south of the Rio Grande, Central America, South America, all Caribbean islands, are filed in green folders, alphabetically by genus, then by species, and within a species alphabetically by country
  5. All cultivated plants are filed in blue folders, alphabetically by genus, then by species, without regard to geography
  6. Plants from the botanical gardens and arboretum of PSU are in yellow folders, directly under the blue folders for other cultivated plants

N.B.: The order of the folders within a genus in the herbarium cases is always the same: Buff on top, then red, then orange, then green, then blue, then yellow on the bottom, as in the 1-6 listing just above.

Removal of Material from Sheets or Packets for Research Purposes

Removal of sub-samples from the herbarium specimens for scientific purposes, such as anthers or sporangia for pollen or spore preparations, or pieces of leaves for DNA analysis, is permitted but must be done under supervision of the Curator, the Emeritus Curator, or the Director. Some hundreds of the existing sheets show removal of material for pollen or spores, and such annotation should be added to all sheets sub-sampled.

For pollen and spore sub-sampling, there are important directions in the book, Paleopalynology, 2nd Ed., 2008, pp. 619-620.