Proposed Hay Grading Standards Based on Laboratory Analyses for Evaluating Quality

This paper constitutes a report from the Forage Analysis Subcommittee of the Hay Marketing Task Force organized by the American Forage and Grassland Council and presents a proposal for the establishment of market hay grades. The need for hay standards that will more adequately express feed value in forages and that will communicate this value among agricultural scientists, agri-business clientele, and producers has long been recognized world wide. The Forage Analysis Subcommittee surveyed United States scientists working with forage quality and animal nutrition to obtain a concensus of opinion relative to more precise techniques for evaluating forage quality. Subsequently, research data were collected on forage samples from widely differing climates in the United States. Samples included the following species: alfalfa — Medicago sativa L.; smooth bromegrass — Bromis inermis Leyss.; orchardgrass — Dactylis glomerata L.; reed canarygrass — Phalaris arundinacea L.; tall fescue — Festucaarundinacea Schreb.; ‘Pangola’ digitgrass — Digitaria decumbens Stent.; bahiagrass — Paspalumnotatum Flügge; and ‘Suwannee’ bermudagrass Cynodon Dactylon (L.) Pers. The relationships of acid detergent fiber with in vivo digestible dry matter and neutral detergent fiber with dry matter intake are reported. A relative feed value based upon digestible dry matter intake as an estimate of digestible energy intake is proposed for evaluation of all forages. Five hay grades and one sample grade3 for all legumes and grasses are proposed by the committee.