Growth Form: Alfalfa is a forb/herb; stems with several branches, generally growing horizontally and turning upward (decumbent) or upright (erect); the stems are mostly without hairs or with small soft hairs.
Recorded Range: Alfalfa is an introduced plant that has found its way through most of North America, including Canada and Mexico. In Arizona it is found in the northern, central and southeast parts of the states.
North America & US County Distribution Map for Medicago sativa.
North America species range map for Alfalfa, Medicago sativa:
Click image for full size map.
U.S. Weed Information:Medicago sativa is listed in:
Weeds of the United States and Canada
Plants included here may become weedy or invasive.
U.S. Wetland Indicator: In North America Medicago sativa has the following wetland designations:
Alaska, UPL;
Arid West, UPL;
Atlantic and Gulf Coastal Plain, UPL;
Caribbean, UPL;
Eastern Mountains and Piedmont, UPL;
Great Plains, UPL;
Hawaii, UPL
Midwest, FACU;
Northcentral & Northeast, UPL;
Western Mountains, Valleys, and Coast, UPL.
FACU = Facultative Upland, usually occur in non-wetlands, but may occur in wetlands
UPL = Obligate Upland, almost never occur in wetlands
Genus Information: In North America, USDA Plants Database lists 39 species for Medicago. Worldwide, World Flora Online includes 134 accepted names and The Plant List has 121 records for Medicago which includes sub-species and varieties.
The genus Medicago was first published in 1753 by Carl Linnaeus, (1707-1778).
In the Southwestern United States: Arizona has 4 species of genus, California has 7 species, Nevada, New Mexico and Utah each have 3 species and Texas has 6 species. Data approximate, subject to revision.
In the United States there are 5 recorded sub-species in Medicago sativa.
Medicago sativa ssp. falcata, yellow alfalfa, (throughout North America);
Medicago sativa ssp. sativa, alfalfa, (throughout North America).
Medicago sativa ssp. caerulea
Medicago sativa ssp. glomerata
Medicago sativa ssp. x tunetana
Comments: In Arizona and elsewhere Medicago sativa has become naturalized. The plants in the photos above were taken at 2,500 feet (762 m) along the road up to Mount Ord, Maricopa County, Arizona.
Alfalfa is grown as an important crop in many countries throughout the world where it was first grown in ancient Iran. In many parts of the world it is called "Lucerne", particularly in the United Kingdom, South Africa, Australia and New Zealand. In the United States, Alfalfa was first introduced in 1736 in Georgia and now is planted in most states. It is naturalized in some states.
Alfalfa, Medicago sativa has attractive flowers, the flowers and their seeds may be visited by hummingbirds and/or small mammals including rodents and granivorous birds in search of nectar or food.
Alfalfa is used as forage by game mammals including Elk, White-tailed and Mule Deer, bighorn sheep, pronghorn and moose. It is also, of course relished by livestock. In addition, its seeds or leaves are known to be eaten by many species of mammals and birds. Mammals feeding on Alfalfa seeds include rodents, rabbits, squirrels and gophers. Birds known to utilize Alfalfa include grouse, pheasant, quail and waterfowl including Canadian Geese.
Alfalfa is also an important cover for nesting and loafing small mammals and birds.
Because of its' early spring growth, Alfalfa is important for use in the rehabilitation of over-grazed ranges.
Beneficial Value to Butterflies, Honey Bees and Insects
Alfalfa, Medicago sativa has attractive flowers, the flowers and their plants may be visited by butterflies, moths, flies, honeybees, Native Bees and other insects in search of food and nectar. Alfalfa is an important pollen source for insects.
U.S.D.A. Natural Resources Conservation Center, Plant Guide;
The U.S.D.A., U.S. Forest Service; Fire Effects Information System (FEIS) has published a comprehensive review regarding the natural history and ecology in the United States, of Medicago sativa. The information is available on-line here.
Etymology:
The genus “Medicago” is from the Greek word "Medlick" or "medick" meaning alfalfa.
