SRU Herbarium

About the Herbarium

The SRU Herbarium (SLRO) contains approximately 18,000 vascular plant collections. The majority of the collections are from North America north of Mexico (primarily the contiguous United States) with a little more than half of the collections being from Pennsylvania. There are approximately a thousand collections from Canada with more than sixteen thousand collections being from 48 of the 50 states in the USA.

The bulk of the vascular plant collections within SLRO are flowering plants. The families with the greatest numbers of specimens within SLRO are the Asteraceae, Poaceae, Fabaceae, Rosaceae. Within the herbarium, for vascular plants, there are 205 families, 1,111 genera, 3,300 species, 3,667 total taxa (including subspecies and varieties). Antennaria collections make up about 5% of the collections at SLRO. The majority of type collections within the herbarium are infraspecific types from the Charleston Mountain Flora collected by I.W. Clokey from Spring Mountains in Nevada. The most well represented collector in the herbarium is from a previous Curator at SLRO, namely K.S. Erdman, who collected throughout the US and parts of western Canada.

Some of the well represented collectors in SLRO based on region include:

  • Pennsylvania: W.E. Manning, J.A. Shafer, L.K. Henry, D. Berkheimer, N.H. Russell, R. Medve, W. Shuffstall, J.G. & C. Chmielewski
  • Canada: O.E. & G. Jennings
  • US Southwest: R. & D. Foster, I.W. Clokey, S.L. Welsh, N.D. Atwood
  • US Southeast: E.S. Ford & N.H. Russell, John Bright, R.K. Godfrey,
  • Ozarks: Delzie Demaree
  • New England: H.E. Ahles

Many of the FAQs about use of the SLRO Herbarium can be found in the herbarium protocol.

Goals of the Herbarium

Our goal is to better understand the flora of western Pennsylvania. It is our goal to report both the overlooked native species plant in Pennsylvania as well as identifying new occurrences of non-native taxa. Students interested in botany are always welcome to contribute to the work of SLRO. See below select published works that have resulted in contributions to the herbarium some of which are student authored publications.  

2018. Bauer, J.L.* and Krayesky, D.M. A preliminary checklist of lichens for Lawrence County, Pennsylvania. Evansia 35(1): 1-5. 

2016. Krayesky, D.M. and Chmielewski, J.G. Additions to the Sphagna of northwestern Pennsylvania: noteworthy collections. Evansia 33(3): 101-105.  

2016. Krayesky, D.M. and Chmielewski, J.G. Noteworthy Collections: New reports of non-native plants in Pennsylvania. Castanea 81(2): 150-154.  

2015. Chmielewski, J.G. and Krayesky, D.M. Noteworthy Collections: Pennsylvania. Castanea 80: 37-42.

* = student author


SLRO is currently collaborating with Mid Atlantic Herbarium Consortium to better examine our collections and the changes to our flora by digitizing our collection. The SLRO collections can be searched through the online database at Mid Atlantic Herbarium Consortium. We are currently geo-referencing our collections. If SRU students are interested in geo-referencing SLRO collections, please contact David Krayesky.