Catalog of the Colorado Flora: A Biodiversity Baseline
William A. Weber and Ronald C. Wittmann
University of Colorado Museum
Boulder, Colorado
University Press of Colorado

Electronic version, revised March 11, 2000. Reports are generated from a database maintained by the authors.


Checklists (for vascular plants, mosses, hepatics, and lichens) and a general bibliography. All files are in *.pdf file format.


  1. Scientific names of families (except for lichens where classification is presently unstable), genera, and species currently accepted by the authors are displayed in boldface.
  2. Scientific names of species. Accepted names are displayed in bold, names used in previous publications on Colorado plants (erroneous reports) are aligned with accepted names, but are italicized. Synonyms are indented following the accepted name or erroneous report.
  3. Comments are frequently included; for example, basionyms, citations, and type specimens for taxa described from Colorado.
  4. Literature References are indicated by codes which may be located in the bibliography.
  5. The bibliography is arranged alphabetically by codes that are formed from the first five letters of the principal author's name and the year of publication.

Special Cautionary Information:

Scientific nomenclature is the most concise way by which taxonomists express their points of view as to recognition of taxa. In the Twenty-first Century, taxonomic concepts are undergoing changes as new techniques of examination, breeding, and analysis of genomes arise. Some of these changes are controversial, involving the recognition of old names for genera that may have been regarded as earlier as subgenera. Family configurations have also undergone change, especially in the last few decades, as the distribution, ecology, and reproductive strategies of species and larger groups become better understood.

Our catalog contains many controversial features, and we are ready to amend our ideas when they are refuted by evidence. Our treatment of the genus Prunus, for example, rests on the premise that the groups we recognize as genera are genetically isolated, have distinctive morphologies, and have had independent histories. We welcome discussion and intelligent opposition to our points of view. We do not insist that our classification be followed in every detail. This is why we give synonyms. The listing of names as synonyms does not mean that they are dead wood. Many taxa now regarded as synonymic were described for seemingly good reasons. New evidence may convince us to elevate some synonyms to legitimate accepted names.

This catalog is based on the senior author's experience of 60 years in the field and laboratory in Colorado and the West, as well as field study of other floras: Australia, northern and central Europe, the Mediterranean, Arctic America, the Galápagos Islands, Chile, and New Guinea. The subjects have included all of the plant groups listed here. The herbarium in which the record rests is at the University of Colorado Museum (COLO), and contains 300,000 vascular plants, 110,000 bryophytes, and 100,000 lichens.

Citing the Catalog:

We suggest a format similar to the following:

Weber, W. A. and R. C. Wittmann, Catalog of the Colorado Flora: University Press of Colorado, Niwot, CO. 1992 (revised electronic version, Jan. 2000).


The user is permitted to quote portions of this Catalog verbatim as long as proper credit is given; however, anyone wishing to incorporate extensive sections (more than about a page) should request permission from the authors. We request that "corrected" or modified versions of the Catalog not be distributed. Those wishing a "pure" version should obtain it directly from the authors, or from this internet site.


Under certain conditions we may be willing to provide a researcher with a copy of the underlying database. Please inquire with the authors.


This document is deceptively complex, errors are easy to make and difficult to detect. We would much appreciate receiving information on inaccuracies and deficiencies of the Catalog.

Please send corrections, comments and questions to: