Of all the feedstuffs livestock consume, hay is probably one of the most variable in terms of quality. Hay can look good and still be low quality, or look bad and be good quality. The best way to know for sure is to have it tested. However, many people never take the time to send off a sample for analysis. What are the factors affecting the quality of hay?
Stage of Maturity
This refers to the growth stage of the plant at the time of harvest. Stage of maturity is by far the most important factor influencing quality. The younger the plant, the higher the quality. I've actually seen common bermudagrass test greater than 20% crude protein on a dry matter basis. If you want to harvest or purchase good-quality hay, pay particular attention to maturity. In southern Oklahoma, we can expect to harvest decent-quality bermudagrass if it's cut prior to mid-June. If you delay much beyond that time, quality rapidly begins declining with the first cutting.
This refers to the proportion of leaves versus stems present and is also related to the stage of maturity, especially in grass hays. The younger the plant, the greater the proportion of leaves. As a grass matures, stems increase or are elevated, thus decreasing the quality of the forage.
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