Services and Policies


Location: The Ada Hayden Herbarium is located on the third floor of Bessey Hall, rooms 344-360, on the campus of Iowa State University (Maps of ISU)
Hours: 8 a.m. to 5 p.m. Monday through Friday. Closed on University Holidays.
Contact: Deb Lewis, Curator, Tel. 515-294-9499 or

Access to the Collection

Photo of Herbarium WorkstationUse of the specimens is limited to bona fide researchers (including graduate students and qualified undergraduates) and must be approved by the Curator or the Director. Training in the handling of specimens will be provided for those who are unfamiliar with standard herbarium procedures. Users who need assistance in retrieving specimens due to a disability or other condition should make prior arrangements with the Curator. Access to the herbarium is free of charge. Information from the specimens is available to researchers and to the general public at no charge. Some restrictions may apply to information about species with special conservation status. The herbarium staff can usually answer simple queries, but researchers should make arrangements for personally acquiring the data if the needed information is extensive or requires special expertise. The herbarium staff provides tours and demonstrations for ISU classes, school groups, clubs, or any other organization as well as members of the general public at no charge. Please contact the Curator well in advance of your visit so that we may best accommodate everyone's schedules. Dried plant material must be frozen for at least a week before it can be brought into the herbarium. Exceptions for some plant groups may be made. Visitors should plan for this or send their specimens in advance.


Loans of specimens are generally made in support of systematic research. With few exceptions, loans are made to institutions, not individuals. Loans for other purposes (e.g., display, demonstrations, reference for illustrations) are considered on a case-by-case basis. All loaned specimens should be carefully handled and properly stored, consistent with standard herbarium practice, and should not be removed from the borrowing institution. We normally do not restrict the size or duration of loans, but reserve the right to do so in special cases. In the case of large loans, partial returns are acceptable. Transfer of loaned specimens from the borrowing institution to a different institution is acceptable only with the written permission of ISC and the agreement of all parties concerned.

Specimens sent out on loan should be annotated before they are returned. We particularly appreciate notification, by annotation or other means, of any unmarked types found in our collections. Annotations should be made on a separate label of 100% rag paper or comparable quality stock; size should be approximately 1" x 3-4" (2.5 x 7.5-10 cm). Annotations should be written with indelible or permanent ink, never with a ballpoint or felt tip pen; if printed from a computer, a high quality ink system is preferred. The accepted name of the taxon, the name of the researcher, his or her institution (herbarium acronym is acceptable), and the date should be included. The annotation label should be glued in a horizontal position (if at all possible) without obscuring the label or previous annotations. Annotations of type specimens should include the basionym, citation of the protologue, and kind of type. Specimens erroneously labeled as types should be annotated as "Not a Type".

We request a reprint or a copy of any publication resulting from studies of our collection, particularly those in which ISC specimens are cited. If this is not possible, the relevant reference citation would be greatly appreciated.

Destructive Sampling

Reasonable dissection of floral or vegetative parts is normally permitted, but all material should be returned to the specimens. If the specimen does not include a packet already, a small packet of 25% rag paper or higher quality stock may be attached. Prior approval must be obtained from the Curator or Director before removal of material for destructive sampling (e.g., DNA extraction, anatomical preparations). Samples may be removed only from specimens with adequate material, and additional damage to the specimen should be carefully avoided. Removal of samples from type specimens is prohibited, except in unusual circumstances and only with prior approval. Annotations of specimens from which material is removed should so indicate, and the nature of the study should be indicated. The herbarium maintains no records on the history of specimen collection or treatment methods, although these methods may affect the results.


We acquire specimens through field or laboratory work by ISU faculty, staff, and students as well as through gifts and exchanges. No funds are available for the purchase of specimens or collections. We reserve the right to send specimens to other institutions if that is more appropriate, and to decline or discard improperly prepared specimens. Labels must be included with specimens deposited at ISC (check with the herbarium staff if unsure of label data content, or quality of paper and ink). We serve as the principal repository for Iowa plant specimens. We also are interested in specimens of Poaceae, especially Bambusoideae, as well as the New World flora generally, but also welcome representative collections from other parts of the world.

Specimens deposited at ISC should have been collected with the proper permits. Documentation may be required, especially for specimens collected in national parks or other conservation entities. Specimens may be deaccessioned if they are duplicated, and be distributed to other institutions. Specimens lacking parts critical for satisfactory identification or lacking useful label information will be deaccessioned and either destroyed or transferred to the teaching collection as appropriate.

Requests for Identification

Unidentified Iowa plant samples may be sent to the herbarium for identification. Samples should be either pressed and dried or wrapped in slightly damp paper towels and placed in a plastic bag. If the latter method is used, the sample should be mailed and received at the herbarium as quickly as possible. Information sent with the sample should include the locality where the sample was collected, if it is cultivated or wild, and a description of the habitat (e.g., roadside, partial shade, weedy in flower bed, etc.). Other notes about the plant that may not be obvious from the sample (e.g., plant height if only a part is sent in, smell, or flower color that may fade during shipment) may be helpful in its identification. There is no fee for individual identification requests, but fees may be assessed for extensive identification assistance associated with a project. Submitted samples will not be returned due to time and cost considerations.

For further information, contact Deb Lewis, Curator, e-mail