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University of Northern Colorado
Herbarium ("GREE")

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Bienvenue; Yokoso; Don Chao; Marhaba; Selamat Datang

Department of Biological Sciences
Ross Hall, Room 1375
501 20th Street, Greeley, CO 80639, USA
FAX: (970)351-2335

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Chamerion angustifolium – Fireweed

Fireweed (Chamerion angustifolium)

Photo: N. Snow


Iris missouriensis – Rocky Mt. Iris

Iris (Iris missouriensis)

Photo: N. Snow

Mission Statement:

UNC Herbarium personnel, 2005

The mission of the UNC Herbarium is to help advance our knowledge of plants.

Our present specific goals are 1): To be an important repository of plant specimens teaching, research, conservation, and educational and outreach programs; 2) To focus on plants from Southern Rocky Mountain region and High Plains of North America; 3) To continually expand the collections to better represent the diversity of vascular plants; and 4) To curating the collection at the highest possible standards.

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The UNC Herbarium ("GREE")

GREE (shortened from "Greeley") is the standard acronym for the UNC Herbarium, which currently has about 35,000 specimens, about 10,000 of which are backlogged (not mounted and filed). Over the past eight years GREE has been the fastest growing herbarium in the region on a percentage basis, having increased its holdings by over 300%. Estimated specimens by geographical origin include: Southern Rockies - 75%, High Plains - 5%, North America at large - 15%, world at large - 5%. Our facilities include were newly renovated in 2002 and currently provide storage capacity for about 65,000 specimens.

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Southern Rocky Mountain Reference Collection (SRMRC)

The SRMRC is a separate collection of one or two specimens (flower and fruit) of each taxon of vascular plant known to occur in the Southern Rocky Mountain region. Its purposes are for use as a teaching tool for BIO 330 (Plant Taxonomy), and more generally to expedite the ability of all herbarium users to confirm tentative identifications without having to spend as much time in the main collections. The SRMRC is also used to provide a source of specimens for educational demonstrations to school classes, civic groups, and other interested visitors. The collection currently has over 2200 taxa and is expanding continuously.

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Important Collections

  • W. A. Harmon (New World Lupinus; general collections from MesoAmerica from early 1970s)
  • N. Snow (Australasian Myrtaceae)

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Type specimens at UNC Herbarium

GREE has 27 type specimens that are filed separately in red folders, most of which are isotypes. However, numerous paratypes of Myrtaceae are filed with the main collections and are indicated as such.

  • Cunoniaceae:
    • Ceratopetalum hylandii Rozefelds& R. W. Barnes
  • Fabaceae (Pea family):
    • Lupinus burkei S. Wats. subsp. caeruleomontanus D. B Dunn & B. J. Cox
  • Myrtaceae (Myrtle family):
    • Austromyrtus glabra N. Snow & Guymer
    • Barongia lophandra Peter G. Wilson & B. P. M. Hyland
    • Gossia lewisensis N. Snow & Guymer
    • Gossia punctata N. Snow & Guymer
    • Gossia sankowskiorum N. Snow & Guymer
    • “Kanakomyrtus sp. mcphersonii “ N. Snow gen. et sp. nov. ined.
    • “Kanakomyrtus sp. revoluta” N. Snow gen. et sp. nov. ined.
    • “Kanakomyrtus sp. prominens” N. Snow gen. et sp. nov. ined
    • Lithomyrtus densifolia N. Snow & Guymer
    • Mitrantia bilocularis Peter G. Wilson & B.P.M. Hyland
    • Piliostigma sessile N. Snow
    • Rhodamnia angustifolia N. Snow & Guymer
    • Rhodamnia longisepala N. Snow & A. J. Ford
    • Rhodamnia sp.hylandii” N. Snow sp. nov. ined.
    • Rhodamnia sp.sharpeana N. Snow sp. nov. ined.
    • Rhodomyrtus sp. "longisepala" Csizmadi & N. Snow ined.
    • Ristantia gouldii Peter G. Wilson & B. P. M. Hyland
    • Sphaerantia chartacea Peter G. Wilson & B.P.M. Hyland
    • Sphaerantia discolor Peter G. Wilson & B. P. M. Hyland
    • Stockwellia quadrifida D. J. Carr, S. G. M. Carr, & B. Hyland
    • Uromyrtus acuminata N. Snow ined.
    • Uromyrtus lamingtonensis N. Snow & Guymer
    • Uromyrtus sp. “rigidifolius" N. Snow ined.
    • Uromyrtus tenellus N. Snow & Guymer
  • Poaceae (Grass family):
    • Leptochloa simoniana N. Snow

What are type specimens?

Type specimens are nomenclatural standards that serve as the permanent physical link to a scientific name. They are irreplaceable and typically curated with extra care, and often locked away from the main collections.

Why are type specimens needed? When a botanist finds a new species, it is must be described following conventions contained in the International Code of Botanical Nomenclature (URL below). Once this is accomplished, the type specimen(s) are the permanent physical example of that name. When writing taxonomic revisions and monographs, taxonomists routinely check type specimens to confirm that scientific names are being applied properly. This is necessary because names occasionally are misapplied, sometimes for hundreds of years. Such errors can be corrected only if the botanist has checked the name and the description of that species against a type specimen.

What are the different categories of type specimens?

The holotype is the single specimen designated by the describing author (of a new species) as the type specimen. The herbarium in which the holotype is deposited must be indicated in the original description. If duplicate material of the holotype was collected at the same time and place by the same collector (not necessarily the person who is describing the new species), then such duplicate specimens are called isotypes. Botanists routinely collect isotypes of known new species, since in rare cases holotypes have been destroyed. For example, the herbarium at Berlin tragically lost many of its type specimens from bombing campaigns during World War II.

The convention to adopt type specimens dates back to 1930, at a Botanical Congress in Cambridge, although the idea to adopt types was presented even earlier. Prior to that time, many plants species were described in the literature with little or no mention of specimens that represented that species. In such cases, botanists eventually must designate a lectotype. A lectotype is designated by a later researcher in cases where a holotype was never designated. Designation of lectotypes requires extensive research, and preference is given to specimens located at the herbarium of the original author who made the description, or among material believed to have been seen by the original author. If duplicate specimens exist of the lectotype, then these are isolectotypes.

The International Code of Botanical Nomenclature, which governs the description of species and use of type specimens, is re-analyzed every six years prior to and at the International Botanical Congress. At that time, proposals to amend or change the Code are debated and voted upon. The last Congress in 2005 in Vienna, Austria. The next Congress, in 2011, will be Melbourne, Australia.

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Taxonomic Organization of GREE

GREE is organized phylogenetically by family following the recently published Angiosperm Phylogeny Group II classification (Bot. J. Linn. Soc. 141: 399-436. 2003). It is probably one of only a few herbaria in the world to be based on such a recent classification. Genera, species, and infraspecific taxa follow the "Provisional Checklist of Vascular Plants for the Southern Rocky Mountain Interactive Flora (SRMIF)" by Snow and Brasher. For taxa from other parts of North America, we largely follow Kartesz and Meacham (Synthesis of the North American Flora)."

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Databasing of specimens at GREE uses the Linux-based SuSE with MySQL, which was developed by Ward Fisher at Colorado State University with funding support from the National Science Foundation. The UNC Herbarium database is part of a federation of databases, including those located at Colorado State Univeristy, University of Colorado-Boulder, University of Wyoming. When completed, the individual databases will be linked into a single master database.

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Identifying plant material for the public at large is not a part of the Mission of the UNC Herbarium, and no staff is available to support such requests. Colorado State University, whose outreach mission includes such requests, can be contacted at ( However, as part of the curator's taxonomic research, specimens of the following genera will be annotated and returned at no charge, provided at least one gift specimen is sent per determination with the specimens to be annotated: Leptochloa (including Diplachne), Rhodamnia, Pilidiostigma, Austromyrtus s.l., Lithomyrtus, Uromyrtus, Gossia, Lenwebbia, Archirhodomyrtus.

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Exchange Policy

The UNC herbarium has an active exchange program and is seeking exchanges from other institutions. Geographically our order of preference is specimens from: 1) Southern Rocky Mountains; 2) High Plains; 3) North America; 4) New World; 5) Old World. In addition, we seek non-cultivated specimens of Myrtaceae world-wide, especially the genus Eugenia. Institutions interested in either a one-time or on-going exchange are encouraged to contact the curator.

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Loan Policy

Loans of herbarium material will be approved for anyone doing scientific research at a recognized institution. Loans are typically made for a period of one year. Destructive sampling of small portions of material for DNA studies, SEM work, etc. generally will be allowed, although permission must first be requested. Contact the curator for additional details regarding loans.

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Herbarium Tours

As part of the educational outreach mission of UNC, GREE is happy to offer herbarium tours. Tours typically will be of about 30 minutes duration and are designed to be flexible to meet the interests and needs of the group. We are particularly interested in giving tours to local school groups of any age. Contact the curator to schedule a tour (

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Interactive Identification Keys

The use of interractive identification keys to disseminate taxonomic data is expanding rapidly. In contrast to printed dichotomous keys, interactive keys allow the user to select any character (trait) of the unknown specimen in any order from the choices available on the computer screen. The interactive key removes species that do not match the selected characters. Interactive keys typically expedite the process of identification considerably and typically provide illustrations and photos of both features and of species. Many other options for identification are available, depending on the software used. GREE is committed to promoting the use of on-line interactive keys as research and pedagogical tools using Lucid software ( A recently produced key to the species of the genus Gossia (Myrtaceae) in Australia can be accessed at: (See below also for Southern Rockies).

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Southern Rocky Mountain Interactive Flora

The Southern Rocky Mountain Interactive Flora (SRMIF) is an NSF-supported project to create an on-line key to all taxa of vascular plants from the Southern Rocky Mountain region. This area includes all of Colorado, northcentral New Mexico, and southern Wyoming. A checklist of vascular plants (with synonymy) can be downloaded at The project is not anticipated to be completed until 2005, although a key to families is currently available at Photos will be available for the vast majority of taxa. Individuals willing to donate high quality photos or digital images (preferably vouchered) can contact the curator for details. We thank the many people who have done so thus far, including: D.Wilken, D. Pratt, A. Wood, J. Ackerfield .

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Systematics Library

The herbarium has approximately 1200 books, reprints, and journals related to plant systematics. Most belong to the curator and can be used in, but not removed from, the herbarium. Reprints are organized alphabetically by first author’s surname. The collection is particularly rich in literature our geographical region, of Poaceae (ca. 650 items) and Myrtaceae (ca. 350 items). Nearly all recent Floras of our region are available.

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Recent Activities

GREE is is active regionally and internationally in most aspects of herbarium activities. It has an active acquisition program via collections and exchange. The collections are used heavily by Plant Taxonomy students (BIO 330) during the fall semester when keying out their plant collections. In the past decade GREE has shipped or received specimens from 50 institutions representing 12 countries. Recent research supported by the UNC Herbarium has included the description of three new genera and approximately fifty new species in Myrtaceae (some not yet published) by the curator. Jessie Csizmadi recently defended her Masters Thesis of Rhdomyrtus using DNA sequencing and morphological techniques. Jeffrey Brasher is a doctoral candidate working on the Southern Rocky Mountain Interactive Flora. Michael Schiebout is a masters student who has collected over 9,200 specimens in northeastern New Mexico for a florsitics study. The herbarium typically has one or more undergraduate students employed as work-study or serving in a volunteer capacity. Neil Snow is finishing a revision of several genera of Myrtaceae for the Flore de la Nouvelle Caledonie series and recently initiated a revision of Eugenia from Madagascar. GREE has databased approximately 7500 specimens from the Southern Rockies recently with support from the National Science Foundation.

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Donating Specimens to UNC Herbarium

The UNC herbarium will gladly accept high quality specimens for addition to the main collections. Specimens must include a detailed label, including latitude and longitude coordinates. We prefer specimens from areas in the following priority: 1) High Plains (see details above regarding coverage); 2) Colorado; 3) North America; 4) New World; 5) Old World. Specimens of neotropical Myrtaceae are also particularly desired, especially non-cultivated species, and particularly of the genus Eugenia. Unmounted specimens are preferred.

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Volunteer Opportunities

GREE benefits enormously from the help of volunteers, who annually log several hundred hours of service to the herbarium. Persons who can consistently commit 5 hours or more a week to the herbarium are encouraged to contact the curator ( Volunteer activities include mounting and filing specimens, making labels, databasing specimens, unpacking and packing loans and exchanges, and organizing reprints and other literary material. GREE thanks the following for their volunteer work in the herbarium: Bob Williams (1998-2006), Marilyn Orris (2004-2005), MaryJane Niemann (2004-2006); Marty Arrington (2005), and Pamela Smith (2006).

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What is a herbarium?

A herbarium is a collection of pressed, dried plant specimens used in research, teaching and outreach. Herbarium specimens typically are mounted on thick, acid-free paper measuring approximately 18 x 12 inches. When dried thoroughly, mounted properly, and protected from insects and moisture, herbarium specimens will last several hundred years.

Each specimen has a label that indicates the scientific (=Latin) name of the specimen, who collected the plant, the collector(s)' number, and date and place of collection. Labels generally contain additional data such legal descriptions (latitude/longitude, or Township/Range), habitat and other ecological conditions, and associated species. With the advent of Global Positioning Systems (GPS) technology, accurate latitudinal and longitudinal data ("geo-referencing") are now considered essential for new collections. Such data are extremely useful for applications with Geographical Information Systems (GIS) technology.

An important mission of any active herbarium is the lending of specimens to recognized institutions for scientific research. GREE currently has several thousand specimens on loan to it for research and several hundred on loan to other institutions.

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Why are herbaria useful?

Herbaria are important because they are the storehouse of most scientific data relating to plants.

Each herbarium specimen is a source of scientific data: It represents a known (= "vouchered") record of a plant species as having grown at a particular place at a particular time. Herbarium specimens typically represent the majority of research material available to plant taxonomists who write taxonomic revisions and monographs. Herbarium specimens are also used widely in beginning plant biology and plant taxonomy courses.

Recent estimates suggest that at least 325,000 species of vascular plants exist worldwide. This figure is up from a number of about 250,00 that was cited in the recent past. Nobody knows the exact number of species. However, it may surprise many to learn that many thousands of plant species still remain to be discovered and formally described in the literature. Most new species will come from tropical areas. The curator of GREE is actively involved with this type of research, focusing primarily on the myrtle family (Myrtaceae).

Despite the concentration of undescribed species in tropical regions, Hartman and Nelson (1998; Taxonomic Novelties from North America North of Mexico, Missouri Botanical Garden Press) recently documented that 1,197 new plant taxa were described from North America (excluding Mexico) from 1975-1994. Herbaria are the repositories in which nearly all taxonomic data ultimately reside (in the form of preserved specimens).

One important spin-off of floristic research - general plant collecting in specified regions - is that it tends to remove candidate species from consideration for addition to the US Endangered Species List. Well over 100 species have been removed from the candidate list, due largely to floristic studies carried out at the Rocky Mountain Herbarium.

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Other herbaria


The world's largest herbarium is located at the Natural History Museum in Paris, France, which has approximately 9 million specimens. Some of the other large, historically important herbaria include: Komarov Botanical Institute in St. Petersburg, Russia; Royal Botanic Gardens, in Kew, England; Botanical Gardens and Museum in Berlin, Germany; Royal Botanic Gardens in Melbourne, Australia; Swedish Museum in Stockholm; the Rijksherbarium in The Netherlands; National Herbarium in Pretoria, South Africa; Herbário Nacional in Mexico City; Instituto Nacional de Biodiversidad (InBIO) in Costa Rica. However, many other collections worldwide are in excess of a million specimens.


Among the largest and most active herbaria are those at the Missouri Botanical Garden (St. Louis), Smithsonian Institution (Washington, D.C), New York Botanical Garden (Bronx), Harvard University Herbaria (Cambridge), Field Museum (Chicago), University of California (Berkeley), University of Texas (Austin), and University of Michigan (Ann Arbor).

High Plains Region:

Rocky Mountain Region

(see URLs below) the largest herbaria are at the Rocky Mountain Herbarium at the University of Wyoming (ca. 750,000 specimens), University of Colorado at Boulder (ca. 500,000), Brigham Young University (ca. 460,000), Utah State University (ca. 235,000), Montana State University (c. 80,000), and Colorado State University (c. 75,000).

Summary of Vascular Plants of the Southern Rocky Mountain Region

The tentative numerical summaries of plant taxa from the Southern Rocky Mountain Region based on Snow and Brasher (2003) are:

  • Families: 127
  • Genera: 795
  • Species: 3400 (including 40 of hybrid origin)
  • Infraspecific taxa (subspecies and varieties): 735
  • Regional endemics: 97
  • Presumed extinct: 1 (Cryptantha aperta)

Colorado botanical links

Rocky Mountain botanical links

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Professional Organizations

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Major Botanical Gardens with Research Herbaria (USA)

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Links for Taxonomic Research