This is a checklist of plants growing within a forty-mile radius of Arizona's State Capitol Building in Phoenix. Its boundaries roughly include the following perimeter sites in parts of Gila, Maricopa, Pinal and Yavapai counties: Hassayampa River Preserve, Lake Pleasant, Seven Springs, Tortilla Flat, western part of the Superstition Mountains, Sacaton, just north of Casa Grande and Gila Bend. The Metropolitan Phoenix area, including the surrounding mountains, is often referred to as "The Valley of the Sun." The vegetation here is predominantly Upper Sonoran Desert, but includes some species of Chaparral, Desert, Grasslands and Pinyon-Juniper zones on its mountain "islands."

Goals
The goals of this study are: 1) to provide a baseline database of native and cultivated vascular plants that grow in this area and where they occur according to specific subdivisions outlined below; and 2), to study changes that might occur during the first decades of the 21st century, one of the goals of the Central Arizona-Long-Term Ecological Research project (CAP-LTER).

Basis
The checklist is based on native and established alien plants (Part One) and plants commonly used in cultivation (Part Two). Each entry requires documenting specimens deposited in the Arizona State University Herbarium, Tempe (ASU), the Herbarium of the Desert Botanical Garden, Phoenix (DES), or as verified in other registered herbaria as indicated by their acronyms (Holmgren, et al. 1990). Included herein are local floras (theses and unpublished reports) prepared by ASU students under the direction of Donald J. Pinkava: Lake Pleasant Regional Park (Lehto 1970), White Tank Mountains Regional Park (Keil 1970, 1973), Sierra Estrella Regional Park (Sundell 1974), McDowell Mountains Regional Park (Lane, 1976, 1981), Buckeye Hills Recreational Area (Pierce 1979), Usery Mountain Semi-regional Park (Walden, unpubl.), Thunderbird Semi-regional Park (Montgomery, unpubl.), San Tan Mountains Semi-regional Park (Damrel, unpubl.), Superstition Wilderness Area (in part) (Rice 1994), The ASU Arboretum (Damrel, unpubl.), Glendale Library Xeriscape Garden (Bond and Ickert-Bond, unpubl.); and under the direction of Duncan T. Patten: Hassayampa River Preserve (Wolden 1993, Wolden et.al. 1995), and Camp Creek (Abel 1980). Also included is a South Mountain Park flora by Daniel and Butterwick (1992). Miscellaneous collections have been added by students, friends and the staff of the ASU Herbarium or via exchange with other herbaria.

Computerization
Leslie Landrum directed the design and data entry that produced the checklist. The Phoenix Flora database may be used in various ways. Various fields describe each species, including the epithets, authors, common name; geography - presence/absence in certain county and city parks and other specific sites; habit - tree, small tree, shrub, subshrub, vine, perennial herb, annual herb, scapose, bulb.

One can query the database based on any combination of fields, e.g., 1) all the plants in South Mountain Park; 2) all trees and shrubs found in both the White Tank Mountains and the McDowell Mountains Regional Parks; 3) all plants found in the Sierra Estrella Regional Park but not found in the McDowell Mountains Regional Park; 4) all the species in the Asteraceae in the Phoenix area; 5) all the plants that have been found in the Sierra Estrella Mountains Regional Park, and in no other park.

The database has been made and can be used using dBase IV, but can easily be transferred to Microsoft Access. The present on-line preliminary checklist (ASU Vascular Plant Herbarium web site) has many plants illustrated with photos and scanned herbarium sheets on the net. There are hundreds of species linked to the "Trees and Shrubs of Arizona" class list. Linking of photos of the Phoenix Flora is ongoing as images become available.

Several individuals who generously shared their expertise and co-operation include: Richard and Steffi Bond, Nancy Grimm, Richard Harris, Wendy Hodgson, J. Kenneth Hoober, David J. Keil, Elinor Lehto, Charles Redman, Louisa Ballard, Samuel Scheiner, Roisan Rubio, Liz Slauson, A. Wayne Smith and Shirley Stapleton.

Abel, Bonnie Hill. 1980. The Sonoran desert-chaparral transition: microenvironmental effects on the vegetational pattern. M. S. thesis, Arizona State University, Tempe.

Arizona Municipal Water Users Association. 1991. XeriscapeGardens: Plants of the Desert Southwest. Arizona Municipal Water Users Association, Phoenix, Arizona.

Backhaus, B. 1995. The Arboretum at Arizona State University--A Guide. Arizona State University, The Arboretum, Tempe.

Bailey, L. H. 1935. The Standard Cyclopedia of Horticulture. Vols. 1-3. Macmillan Publishing Company, New York.

Bailey, L. H. 1924, 1949. Manual of Cultivated Plants. Macmillan Publishing Company, New York.

Bailey, L. H. and E. Z. Bailey, and staff of Liberty Hyde Bailey Hortorium. 1976. Hortus Third: A Concise Dictionary of Plants Cultivated in the United States and Canada. Macmillan Publishing Company, New York.

Benson, L. 1969. The Cacti of Arizona. Ed. 3. University of Arizona Press, Tucson.

Blakely, E. R. 1958. Papago Park yields plant new to Arizona. Saguaroland Bulletin 12 : 9.

Bond, R. and S. Ickert-Bond. n.d. Glendale Library Xeriscape Garden. no publisher.

Brown, D. E., N. B. Carmony, C. H. Lowe and R. M. Turner. 1976. A Second locality for native California fan palms (Washingtonia filifera ) in Arizona. Journal of the Arizona Academy of Science 11: 37-41.

Burgess, R. L. 1963. A Preliminary Report on the Flora and Vegetation of the Regional Park System of Maricopa County, Arizona. Fargo, North Dakota. (Mimeographed, unpublished, 46 pp.).

Butterwick, M. 1980. Hesperaloe funifera (Agavaceae) in Texas. Sida 8 (3): 314-315.

City of Scottsdale Parks Division. n.d. McCormick Railroad Xeriscape Arboretum. City of Scottsdale Parks Division, Scottsdale, Arizona.

Damrel, D. n.d. Vascular Flora and Vegetation of San Tan Mountains Semi-regional Park. Unpublished.

Damrel, D. n.d. Vascular Flora of the ASU Arboretum. Unpublished.

Daniel, T. F. and M. L. Butterwick. 1992. The flora of the South Mountains of south-central Arizona. Desert Plants 10: 99-119.

Desert Botanical Garden. 1997. A Visitor's Guide to 20 Plants on the Desert Discovery Trail. Desert Botanical Garden, Phoenix, Arizona.

Earle, W. H. 1986. Cacti of the Southwest. Rancho Arroyo Book Distributor, Tempe, Arizona.

Ewan, J. 1936. Bibliography of the botany of Arizona. The American Midland Naturalist 17: 430-454.

George, A. S. and collaborators. 1988. Flora of Australia, Volume 19: Myrtaceae, Eucalyptus, Angophora. Australian National Government Publishing Service, Canberra.

Graf, A. B. 1976. Exotica; Series 3: Pictorial Cyclopedia of Exotic Plants from Tropical and Near-Tropic Regions. Ed. 8. Roehrs Company, Rutherford, New Jersey.

Graf, A. B. 1985. Exotica; Series 4 International: Pictorial Cyclopedia of Exotic Plants from Tropical and Near-Tropic Regions: a Treasury of Indoor Ornamentals for Home, the Office or greenhouse--in Warm Climates the Patio and the Garden Outdoors. Ed. 12. Roehrs Company, Rutherford, New Jersey.

Graybosch, R. 1981. Notes on Arizona Poaceae. Journal of the Arizona-Nevada Academy of Science 16: 83-84.

Haynes, R. R., D. H. Les and M. Král. 1998. Two new combinations in Stuckenia, the correct name for Cologeton (Potamogetonaceae). Novon 8: 241.

Hertrich, W. 1960. Palms and Cycads, Their Culture in Southern California as Observed in the Huntington Botanical Gardens. Abbey Press, Pasadena, California.

Holmgren, P. K., N. H. Holmgren, L. C. Barnett (eds.). 1990. Index Herbariorum. Part I: The Herbaria of the World. Ed. 8. New York Botanical Garden, Bronx, New York.

Humphrey, R. R. 1979. The Boojum and Its Home. The University of Arizona Press, Tucson.

Jepson, W. L. 1953. A Manual of the Flowering Plants of California. University of California Press, Berkeley, Los Angeles, London.

Johnston, M. C. 1962. The North American mesquites: Prosopis sect. Algarobia (Leguminosae). Brittonia 14: 72-89.

Kartesz, J. T. 1994. A Synonymized Checklist of the Vascular Flora of the United States, Canada and Greenland. Vols. 1-2. Ed. 2. Timber Press, Portland, Oregon.

Kearney, T. H., R. H. Peebles, and collaborators. 1951. Arizona Flora. Ed. 2. with supplement (1961) by J. T. Howell, E. McClintock and collaborators. University of California Press, Berkeley and Los Angeles.

Keil, D. J. 1970. Vegetation and Flora of the White Tank Mountains Regional Park, Maricopa County, Arizona. M. S. thesis, Arizona State University, Tempe.

Keil, D. J. 1973. Vegetation and Flora of the White Tank Mountains Regional Park, Maricopa County, Arizona. Journal of the Arizona-Nevada Academy of Science 8: 35-48.

Kramer, J. 1975. Fences, Walls and Hedges for Security. Scribner Publishing Company, New York.

Lane, M. A. 1976. Flora and vegetation of the McDowell Mountains Regional Park, Maricopa County, Arizona. M. S. thesis. Arizona State University, Tempe.

Lane, M. A. 1981. Vegetation and flora of the McDowell Mountains Regional Park, Maricopa County, Arizona. Journal of the Arizona-Nevada Academy of Science 16: 29-38.

Lane, M. A. and D. J. Keil. Glinus radiata (Aizoaceae), chromosome counts and range extension to Arizona. Madroņo 23: 457.

Lehto, E. 1970. A Floristic Study of Lake Pleasant Regional Park, Maricopa County, Arizona. M. S. thesis, Arizona State University, Tempe.

Lehr, J. H. 1976. Some additions to the flora of Arizona. Journal of the Arizona Academy of Science 11: 29.

Lehr, J. H. 1978. A Catalogue of the Flora of Arizona. Desert Botanical Garden, Phoenix, Arizona.

Lehr, J. H. 1979. Three additions to the flora of Arizona. Journal of the Arizona Academy of Science 14: 18.

Lehr, J. H. and D. J. Pinkava. 1980. A Catalogue of the Flora of Arizona. Supplement I. Journal of the Arizona-Nevada Academy of Science 15: 17-32.

Lehr, J. H. and D. J. Pinkava. 1982. A Catalogue of the Flora of Arizona. Supplement II. Journal of the Arizona-Nevada Academy of Science 17: 19-26.

Leuenberger, B. E. 1989. Lectotypification of Cereus hexagonus (L.) Miller (Cactaceae) and taxonomic notes on related taxa from South America. Botanische Jahrbücher, Bd. 111 (2): 145-164.

Luckow, M. 1996. The cultivated species of Cassia, Senna and Chamaecrista (Leguminosae). Baileya 23: 195-240.

Manual of Climbers and Wall Plants. Consultant ed. J. K. Burris; Series ed. M. Griffiths. 1994. Timber Press, Portland, Oregon.

Mason, Jr., C. T. and W. E. Niles. 1968. Notes on the flora of Arizona , IV. Madroņo 19 (5): [Urtica urens]Mason, Jr., C. T., R. K. Van Devender and G. D. Starr. 1986. Notes on the flora of Arizona, VII. Desert Plants 8 (1): 38-40. [Hydrilla verticillata, Eleocharis parvula var. anachaeta, Mesembryanthemum nodiflorum]

McCleary, J. A. 1957. Notes on Arizona plants. The Southwestern Naturalist 2: 152-154.

Mosyakin, S. L. 1996. A taxonomic synopsis of the genus Salsola (Chenopodiaceae) in North America. Annals of the Missouri Botanical Garden 83: 387-395.

Miller, V. n.d. Campus Woody Plant Walk-- North Mall. Unpublished.

Montgomery. n.d. Vegetation and flora of Thunderbird Semi-regional Park, Maricopa County, Arizona. Unpublished.

Phoenix Parks and Recreation Department. n.d. Trees and Shrubs of Encanto Park. Phoenix Parks and Recreation Department, Phoenix, Arizona.

Pierce, A. L. 1979. Vegetation and flora of Buckeye Hills Recreational Area, Maricopa County, Arizona. M. S. thesis. Arizona State University, Tempe.

Pinkava, D. J. 1985. Plants new to Arizona flora-- VIII and distributional records of obnoxious weeds and other noteworthy species. Journal of the Arizona-Nevada Academy of Science 20: 91-92. [Calyptocarpus vialis, Hedypnois cretica, Cardamine hirsuta, Cyperus difformis, Hydrilla verticillata, Spirodella punctata]

Pinkava, D. J. and E. Lehto. 1968. Plants new to Arizona flora. Journal of the Arizona Academy of Science 5 (1): 27. [Eichornia crassipes, Urtica urens]

Pinkava, D. J., E. Lehto and Keil, D. J. 1969. Plants new to Arizona flora-- II. Journal of the Arizona Academy of Science 5 (4): 226. [Chenopodium pumilo, Anthriscus scandicina]

Pinkava, D. J. and E. Lehto and D. J. Keil. 1970. Plants new to Arizona flora-- III and new distribution records of noteworthy species. Journal of the Arizona Academy of Science 6 (2): 134. [Amaranthus crassipes]

Pinkava, D. J., E. Lehto, T. Reeves and L. McGill. 1978. Plants new to Arizona flora-- VI and new distribution records of noteworthy species Journal of the Arizona Academy of Science 13 (3): 84-85. [Mesembryanthemum crystallinum, Heliotropium procumbens Mimulus micranthus, Shepardia arvensis].

Pinkava, D. J., E. Lehto, T. Reeves and E. Sundell. 1975. Plants new to Arizona flora-- V. Journal of the Arizona Academy of Science 10 (3): 146-147. [Rumex dentatus, Raphanus sativus, Malva sylvestris ssp. mauritiana].

Pinkava, D. J. and E. Lehto. 1970. A Vegetative Key to the Cultivated Woody Plants of the Salt River Valley, Arizona. Published by the authors. Printed by Tempe Daily News, Tempe, Arizona.

Pollard, E., Hooper and N. W. Moore. 1975. Hedges. Taplinger Publishing Company, New York.

Pruski, J. F. and G. L. Nesom 1992. Glandularia x hybrida (Verbenaceae), a new combination for a common horticultural plant. Brittonia 44 (4): 494-496.

Rehder, A. 1947. Manual of Cultivated Trees and Shrubs Hardy in North America. Ed. 2. Macmillan Publishing Company, New York.

Rehder, A. 1949. Bibliography of Cultivated Trees and Shrubs. Arnold Arboretum, Jamaica Plains, Massachusetts.

Rice, K. C. 1994. Vegetation and Flora of the Superstition Wilderness Area, Central Arizona. M. S. thesis, Arizona State University, Tempe.

Rominger, J. M. 1982. Additions to the flora of Arizona. Journal of the Arizona-Nevada Academy of Science 17: 52-53.

Rubio, R. 1998. An Aerial Guide to the Trees on the Campus of Arizona State University. Unpublished manuscript.

Starr, G. 1997. A revision of the genus Hesperaloe (Agavaceae). Madroņo 44 (3): 282-296.

Stohlgren, T. J., D. Binkley, G. W. Chong, M. A. Kalkhan, L. D. Schell, K. A. Bull, Y. Otsuki, G. Newman, M. Bashkin, and Y. Son. 1999. Exotic plant species invade hot spots of native plant diversity. Ecological Monographs 69 (1): 25-46.

Sundell, E. G. 1974. Vegetation and flora of Sierra Estrella Mountains Regional Park, Maricopa County, Arizona. M. S. thesis, Arizona State University, Tempe.

Taylor's Guide to Ground Covers, Vines and Grasses. 1987. Ed. 1. Houghton Mifflin Publishing Company, Boston, Massachusetts.

True, L. F., J. W. Little and H. F. Tate. n.d. Trees for Maricopa County. Cooperative Extension Service of the University of Arizona, Phoenix, Arizona.

Vincent, M. A. and A. W. Cussick. 1998. New records of alien species in the Ohio vascular flora. Ohio Journal of Science 98 (2): 10-17.

Walden, B. n.d. Vegetation and flora of Usery Mountains Semi-regional Park, Maricopa County, Arizona. Unpublished.