Spring black stem and leaf spot is usually a problem only on the first cutting. Regrowth from this cutting may become infected but disease severity is generally light. This not only reduces yield but significantly lowers the quality of the hay. In Nebraska the disease becomes severe after cool, wet weather. Control Early cutting is recommended if spring black stem and leaf spot is prevalent on the lower portion of plants.
Scout fields weekly in spring to determine the extent of disease development.
Decide whether to cut early based on the results of scouting fields and weather forecasts. Don't delay the decision to cut early, otherwise most of the leaves may have been lost by harvest. Ideally, one-tenth bloom is the optimum growth stage for harvesting while maintaining forage quality and limiting premature leaf loss due to disease. If the field is recovering from winter injury, it may be necessary to delay the first cutting at the risk of foliage loss to spring black stem and leaf spot. A few moderately resistant cultivars have been developed.