Department of Ecology, Evolution, and Organismal Biology

Ada Hayden Herbarium (ISC)

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Got a question or comment? Contact us at (515) 294-9499 or

herbarium logo
Logo design by our friend and colleague Anna Gardner (1958-2006).

The Ada Hayden Herbarium

has the largest collection of Iowa plants and fungi, containing over 600,000 specimens of vascular plants, bryophytes, fungi, and lichens. Functioning primarily as a research facility important for taxonomic studies (occurrence, distribution, and relationships of plants), it is also used for identifying unknown plants. Specimens are loaned to specialists at other institutions around the world to support research. Loans from other institutions allow our researchers access to other herbaria. Recently, herbaria have become a source of materials to use in molecular studies and to support basic research on biodiversity.

Announcing a big change!

Easily search for the Ada Hayden Herbarium records that were previously accessed here -- and more!

The Iowa State University’s Ada Hayden Herbarium searchable database records that were previously available from the search fields at this webpage have nearly all been migrated to national, plant/fungal-group specific Portals as listed below:

For vascular plants (including grass records that had been linked to the Grasses of Iowa website), go to the Northern Great Plains Herbaria Consortium Portal –

For fungi, go to the Macrofungi and Microfungi Collections Consortium’s Mycoportal --

For lichens, go to the Consortium of North American Lichen Herbaria’s portal --

The bryophyte records that have been available by searching here should soon be available on the North American Bryophyte Herbaria Portal here:

It is easy to access and search these databases:

  1. Go to the appropriate portal for vascular plants, fungi or lichens (or bryophytes when available) by clicking one of the URLs (websites) listed above
  2. From the vascular plant portal and the lichen portal, click on Search Collections on the left. For the fungi portal (and soon, the bryophyte one), click the Explore tab at the top, then click “Search Collections”
  3. When you see the list of herbaria in the portal, click Select/Deselect All
  4. Click the small box to the left of Ada Hayden Herbarium, Iowa State University (you can add any additional collections that you wish to include in the search at the same time).
  5. Scroll up or down, if needed, to see Next on the right side of the screen. Clicking Next will take you to the search page
  6. Enter the terms for which you want to search in the appropriate box. For example, if you want to see the entire list of databased records for Iowa, enter Iowa in the State/Province box in the Locality Criteria block. Any number of fields can be used at the same time to narrow your search
  7. Click Search

This should bring up a screen listing the records. To see more of a particular record, click Full record details for that record If you want to see ALL Iowa records, or all those of a particular species or family, from all herbaria in the portal, omit steps three and four, then enter the search terms in the appropriate place(s) on the search screen.

New records are being added frequently, especially to Mycoportal, so check back often!

Questions? Contact the Ada Hayden Herbarium, (515) 294-9499, dlewis{at}iastate{dot}edu

What would happen without plant taxonomists?

Read The Disappearance by Dr. Duane Isley to find out.

Reprinted from Taxon 21(1): 3-12. February 1972.

Help Wanted

Coefficients of Conservatism for Iowa Plants

What is a herbarium?

A herbarium is a plant library, containing dried and pressed plants.

Gossypium herbaceum L. Collected in the Bessey Hall Greenhouse by J.F. Wendel and T.D. Couch, 1988.

Learn More...

See some examples of herbarium sheets !

Database development and bryophyte curation supported by National Science Foundation grant BRC-0646166