Alfalfa is a warm season perennial legume that produces a large amount of high quality, highly paletable forage for livestock of all classes.  Alfalfa is grown to some extent in all 50 states and in many countries throughout the world.  Alfalfa develops a deep tap root which allows the plant to thrive in most climates.  It is this adaptability and quality that has made alfalfa one of the most widely used of all forages.  Although alfalfa is a long lived perennial, most production stands last from 4 to 8 years due to damage by the traffic of hay equipment as the crop is harvested.  Although alfalfa is most commonly planted for hay, it can be used for silage, or processed into pellets, meal or cubes.  Alfalfa also makes a great wildlife food plot component whether used stand alone or mixed withe other legumes.   Since alfalfa is a nitrogen fixing legume, it is necessary to treat the seed with the correct rhizobia to promote nodules in the roots.  These nodules are the site where atmospheric nitrogen is transformed in to a form that can be used by the plant.  Johnston's offers several varieties of alfalfa that are pre-inoculated and fungicide treated. 

A word about legumes and nitrogen fixing:

"Legume" refers to plants that have the ability to convert atmospheric nitrogen ,which is normally unavailable to the plant, to a form of nitrogen that the legume can use for growth.  Rhizobia in the soil "infect" the roots which causes nodules to form on the roots.  These nodules are the site of the conversion of nitrogen to a form which is usable by the plant.  Inoculating the seed places the correct rhizobia in contact with the seed which assures more nodules are produced which results in adequate nitrogen fixation for maximum production potential.  Contrary to some beliefs, legumes DO NOT pump nitrogen into the soil for other plants to use.  The nitrogen that is fixed in the soil following a legume crop is a result of the biodegradation of the roots, nodules, and other plant material from the legume plant.  Legumes can fix great amounts of nitrogen into the soil when plowed in as a "green manure" but they do not transfer nitrogen to non legume plants growing in the same field at the same time.