The area covered by this flora includes all of the INEEL, immediately adjacent foothills of the Lost River and Lemhi Ranges, and all of Big Southern Butte.  The flora consists of 472 species of vascular plants in 59 families;  409 species occur on the INEEL proper.  Six subspecies and eight varieties are included herein, bringing the total number of recognized taxa to 486.  The largest families are the:

  Asteraceae (sunflower family) with 82 species,
  Poaceae (grass family) with 49 species,
  Brassicaceae (mustard family) with 43 species,
  Fabaceae (pea or legume family) with 36 species.

The 472 species can be classified according to life history and growth form as follows:

  Life History:

 320 (67.8%) are perennials
 137 (29.0%) are annuals
 10 ( 2.1%) are biennials
  5 ( 1.1%) are variable.

  Growth Form:

  354 (75.0%) are forbs
  58 (12.3%) are graminoids (grasses/grass-like plants)
  44 ( 9.3%) are shrubs
  11 ( 2.3%) are trees
   3 ( 0.6%) are succulents
   1 ( 0.2%) is a climbing vine.

There are 403 (85.4%) native species, while 69 (14.6%) are introduced.  Of the 403 native species,

  301 (74.7%) are forbs
  44 (10.9%) are shrubs
  44 (10.9%) are graminoids
  10 ( 2.5%) are trees
   3 ( 0.7%) are succulents
  1 ( 0.2%) is a climbing vine.

Of the 69 introduced species,

  31 (44.9%) are annuals
  54 (78.3%) are forbs
  14 (20.3%) are grasses.

Previous lists of vascular plants at the INEEL were prepared by Atwood (1970) and Jeppson and Holte (1978).  Herbarium collections of the INEEL flora were established in the Ray J. Davis Herbarium, Idaho Museum of Natural History, and at the INEEL in 1976.  Additional collections were made by Anita Cholewa and Douglass Henderson in 1982, by James Glennon in 1990 and by Karl Holte and James Glennon in 1993.  Holte and Glennon made extensive searches of the INEEL and immediate vicinity during the exceptionally wet 1993 growing season.  Glennon added eight additional species while collecting data from the long-term vegetation plots in 1995.  Specimens were identified using Flora of Idaho (Davis, 1952), Flora of the Pacific Northwest (Hitchcock & Cronquist, 1973), Vascular Plants of the Pacific Northwest (Hitchcock, et. al.,1955), Intermountain Flora (Cronquist, et. al., 1972, 1977, 1984, 1989, 1994).  Nomenclature follows Beetle and Young (1965) for subspecies of Artemisia tridentata and Barkworth et al. (1983) for members of the Triticeae.  Common names generally are from Hitchcock and Cronquist (1973).  Taxonomy was verified by Karl Holte and nomenclature was updated utilizing The PLANTS database (USDA, 1995).  Voucher specimens for all of the plants listed are in the INEEL or Big Southern Butte collections at the Ray J. Davis Herbarium.