Topics : Species and Forage Variety Trials : Species Fact Sheets : Alfalfa
Characteristics & Adaptation of Alfalfa
Alfalfa has the highest yield potential of the perennial forage crops in Pennsylvania. Yields in excess of 8 tons of dry matter and 4 tons of total digestible nutrients per acre have been obtained regularly. No other perennial crop is equal to alfalfa as feed for livestock, as a cash crop, and as an energy-efficient crop on soils where alfalfa is adapted (Table1).
Selecting an Alfalfa Variety
To capitalize on alfalfa's potential, choose high-yielding varieties with resistance to problem diseases and adequate winter hardiness. These varieties, when properly fertilized and managed, will normally persist for 3 or more years. Avoid using nonadapted common seedlots when growing alfalfa as a perennial forage crop.
Over the past 10 years, more than 150 alfalfa varieties or experimental lines have been evaluated in research trials at three locations in the state. A large number of varieties for which adequate data are available have performed satisfactorily in these research trials. These results appear in Forage Trials Report, an annual publication available at county offices of Penn State Cooperative Extension.
A limited number of alfalfa varieties have the potential of producing secondary roots and have a spreading growth habit. These varieties are referred to as "creeping" alfalfas. However, in a humid climate like Pennsylvania's, these varieties have shown growth habits similar to our more typical bunch-type alfalfas and have shown no yield advantage. Multileaved varieties, those developed to have more than three leaflets per leaf, have recently been marketed throughout Pennsylvania. Unfortunately, these varieties have not consistently shown improved quality or yield over traditional varieties. Select varieties based on disease resistance, winter hardiness, and yield, not because they are multileafs.