The highest quality hay is cut in the early bud stage when the plants have a high proportion of leaves that are rich in protein. As the plants mature, the stems become more coarse and constitute a larger proportion of the total plant, protein percentage decreases, and fiber content increases. However, alfalfa cut at the pre-bud stage produces less forage per acre and continued early cutting seriously weakens the stand. For first cutting, the bloom is often delayed by cool weather and low light intensity. These include fungal and bacterial wilts, leaf spots, crown and root rots, viruses, and nematodes.
Resistant cultivars are available for most of the diseases and nematodes listed.
It causes yellowing of the foliage and stunting of stems. The damage results in significant losses in yield and forage quality, especially loss in carotene. Alfalfa and Alfalfa Improvement. American Society of Agronomy Monograph. Holland, Clive, Pioneer Hi-Bred.