. This document is SS-AGR-93, one of a series of the Agronomy Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. First published in EDIS in June 2002. Original authors were A. T. Adesogan, associate professor, Department of Animal Sciences; L. E. Sollenberger, professor, Agronomy Department; and J. E. Moore, professor emeritus, Department of Animal Sciences. This publication was revised in April 2006 and June 2009. Reviewed June 2012. This publication is a part of the Florida Forage Handbook, an electronic publication of the Agronomy Department. For more information, contact the editor of the Florida Forage Handbook, Yoana Newman, ycnew@ufl.edu. Visit the EDIS website at http://edis.ifas.ufl.edu.