Terrestrial Vegetation
of the U.S. by State
Getting started
Locating books
Government docs
Finding articles
Citing sources
Web sites

compiled by
Ann Watkins

A. How do I get started?

The first step in finding information is to develop an overview of your subject. You might begin with the description of your state in a general encyclopedia.

You might consider reviewing A. W. Kuchler's map, Potential Natural Vegetation of the Conterminous United States. [DANA Reference G 3701 .D2 1975 .K8] The map is also available electronically from the National Forest Service. (http://www.fs.fed.us/fire/fuelman/pnv.htm) Click on "Map Graphics" for a large (825 KB) .jpg file.
In the 1960s, Dr. Kuchler developed the classification system for types of vegetation that would cover the land if there were no disturbances from man or nature. Then he applied this system to create a map of the US. The classification system was adopted as the base for university and government sponsored research and program development. Although other models derived from climate, biomes, ecoregions, and life zones have been developed, the terms for Kuchler vegetation types are commonly used. By noting the types in your state, you can verify the terms in the Library of Congress Subject Headings and incorporate them into your search strategy.

B. How do I locate books?

There are several related general terms with the state or region as a subheading that may be used to search IRIS, our online catalog, by SUBJECT begins with. These headings include:
Plant communities - (state)
Botany - (state) - Ecology
Phytogeography - (state)
Vegetation dynamics - (state)
Plant ecology - (state)
Biogeography - (state)

The specific terms you have identified as vegetation types may also be used to search for books. The states or regions are used as subheadings as well. The following terms are given as examples for searching by SUBJECT begins with:
Forests and forestry - (state)
Forest ecology - (state)
Bog ecology - (state)
Conifers - Ecology - (state)
Trees - (state)
Hardwoods - (state)
Grasslands - (state)

A guide (in Microsoft Word format, 30 KB) is available with more information for searching IRIS.

C. How do I locate government documents?

Various government agencies are interested in terrestrial vegetation since the information contributes to the fulfillment of their goals. The USDA's Forestry Service analyzes land cover to assess the potential for fire. The Environmental Protection Agency is concerned about the environmental impact of hazardous substances particularly on watersheds and may use vegetation as an indicator of harm. The Department of Interior also tracks vegetation, particularly in the national parks.

U.S. Government Publications (Monthly Catalog)
Use this Web-based database to locate government publications distributed through the U. S. Superintendent of Document's Government Printing Office. Dana Library receives approximately 50% of these documents. Many recent publications are available in PDF format and the links to the documents are incorporated in this U.S. Government Publications bibliographic record. For help in locating documents in print format, please see a reference librarian.
Google's Uncle Sam
Another Web search engine for government sites. (http://www.google.com/unclesam)

D. How do I find journal articles?

The terms you identified to locate books in IRIS may be used to search for journal articles. When you find relevant articles, look for the subject headings that have been assigned to the article for more possibilities to search. The following journal indexes have plant ecology related content.
Agricola (1979+ )
BIOSIS Previews (1990+ )
Biological and Agricultural Index Plus (1983+ )
CAB Abstracts (1973+ )
Environmental Science and Pollution Management (1984+ )

You might also try keyword searches on ScienceDirect (1995+ ) or Web of Science (1994+ )

E. How do I cite the books, government documents and journal articles I use in my papers?

Dr. Crow has suggested that you use the citation format (in Microsoft Word format, 20KB) recommended by the Editors of the journal Ecology.

F. Are there any Web sites that will provide support for my information search?

Government agencies and private organizations engaged in natural resource assessment and management have made access to the information collected through their programs a priority. The information may be presented in text as a document and as metadata or graphically in maps. The agences and organizations have agreed to base their programs on the National Vegetation Classification System, a standardized means of describing plants and plant communities. The system was developed by scientists at The Nature Conservancy over a twenty year period and later adopted by government agencies as they collaborated on projects with the Conservancy. The scientists made an effort to accommodate earlier models in the Classification System's structure whether the models were based on existing or successional vegetation.

The National Vegetation Classification System has two major characteristics which contribute to its general acceptance. The system is hierarchical, permitting use on a large scale as well as a narrowly defined level. The system is also flexible, allowing the integration of data collected both in the past and the present. The resulting database is the most comprehensive and current source for biodiversity information. The participating agencies and organizations use the Classification System as a framework for assessment and analysis, adding the results of their studies to enlarge the storehouse of biodiversity information and to further refine the classification.

The following programs, like the National Vegetation Classification System, are projects in progress. The level of detail may not be uniform for each of the states or regions. One program may consider the vegetation across the nation while another looks at rare plants and communities in a particular county. For more information on the National Vegetation Classification System, the Association of Biodiversity Information provides a 2 volume work, Terrestrial Vegetation of the United States: The National Vegetation Classification System in PDF format. (http://www.natureserve.org/library/vol1.pdf)

The following Web sites may serve as intermediary steps in your research, yielding information that you can use to refine your search strategy. The sites are arranged by agency and then program.

Plant Communities of the Midwest
This online publication describes the vegetation types and distribution for twelve Midwest states: IL, IN, IA, KS, MI, MN, MO, NE, ND, OH, SD, and WI. Note that this is a PDF file which will require the Adobe Acrobat Reader. Scientists from the Natural Heritage Network in those states have collaborated on this document that describes in detail 588 plant communities/associations. The work also points out their relationships to one another by organizing the associations into major ecological groups. (http://www.natureserve.org/publications/plantCommunitiesmidwest.jsp)

Mid-Atlantic Ecoregions
This is part of the U.S. EPA Environmental Atlas project, covering DE, MD, NJ, NY, NC, PA, VA, WV, and the District of Columbia. (http://www.epa.gov/maia/html/ecoregion.html)

NatureServe Explorer: Online Encyclopedia of Life
The data collected by the Natural Heritage Network scientists has been organized for you to search for biodiversity information, which is presented in text, charts, and maps. Access points include common or scientific names of animals and plants as well as ecological communities. You may also search by state. Search by clicking on Plants and Animals Select Plants, Vascular and then click on Location. On the next screen, select your state and click on the Search Now button. Be prepared for a very long list! (http://www.natureserve.org)

USDA Forest Service
The Forest Service uses an ecoregion approach to classify the results of their mapping projects. The ecoregions vegetation mapping model was developed by Robert Bailey, a Forest Service biologist, to record existing vegetation. Although Kuchler's model is well established, the vegetation maps depict the plants in the final stage of natural succession rather than the current phase. The Forest Service finds that the application of Bailey's "ecoregions" model results in more appropriate data. The ECOMAP initiative coordinates the efforts of state foresters and USFS staff to map land types and vegetation. Regional offices of the USFS as well as the state forestry departments participate in the ECOMAP project. It is based on ecological units or ecoregions. The USFS offers no direct access to state information. Instead, click on the appropriate regional to find information about the state.
Ecological Subregions of the United States.
This site includes three maps with increasing levels of detail. Clicking on the area of interest leads to an illustrated description of the subregion. The description includes the geographic extent of the subregion, the land surface form, the climate, vegetation and soil. (http://www.fs.fed.us/land/ecosysmgmt/ecoreg1_home.html)
Wildland Fire and Fuel Management
Two affiliated projects of the USDA Forest Service to determine risk of fire and evaluate fire management strategies have resulted in useful nation wide maps showing existing and potential vegetation. These sites include the maps as well as text description. (http://www.fs.fed.us/fire/fuelman/)

US Geological Survey Biological Resources Division. Gap Analysis Program
A state and national effort, the Gap Analysis Program (GAP) describes the status of ordinary species and their habitats so protection might take place before the species become endangered. The program offers a standardized method to collect the data so state findings may be edge-matched to indicate biodiversity patterns from the species and vegetation alliance level to large landscapes. The program's objectives include mapping existing natural vegetation (according to the National Vegetation Classification System, described above), showing the network of conservation lands, and comparing the distribution of vegetation communities with the conservation lands' network. (http://www.gap.uidaho.edu)

Information from the participating agencies' projects is disseminated in professional journals and through the GAP Website. The extent of the Web-based data does not yet reach vegetation types or species. At present, the data displayed on maps shows land cover for the 10 states that have completed their GAP projects. The other states are scheduled to finish by 2002. Some state data and maps have been incorporated into the list of items available from the Nature Conservancy's Map Gallery. This site includes over 50 maps, some depicting ecoregions and vegetation. (http://gis.tnc.org/data/MapbookWebsite/listmaps.php)

University of California, Berkeley, Garth Sciences and Map Library. Checklist of Online Vegetation and Plant Distribution Maps
This site, created by the geology librarians at Berkeley, includes locations of maps for vegetation throughout the world. In the US section, maps of the entire country show Kuchler's Potential Natural Vegetation types as well as the extent of land coverage by a particular plant or plant community. Additional maps are listed by state and county or national park with the state. (http://www.lib.berkeley.edu/EART/vegmaps.html)

As more regional and local agencies post their reports and other publications to the Web, a Google search can result in more information. (http://www.google.com) You might use the subject headings suggested for locating books in combination with your state. As an example, a recent search using the terms, "plant communities" and Wisconsin resulted in the USGS publication, "Wetland plants and plant communities of Minnesota and Wisconsin". (http://www.npwrc.usgs.gov/resource/plants/mnplant/index.htm) A second search using "plant communities" and California uncovered a table with the community name, distribution, climate information, soil type and diversity. (http://geography.berkeley.edu/ProjectsResources/CalPlants/califplanttable.html)

This page was last updated 4 September 2007.
Questions? Comments?