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Topics : Soil Fertility for Forage Crops : Maintenance


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Nitrogen Management for Legumes & Grass Mixtures

A common problem is deciding whether to apply nitrogen to a legume/grass mixture. The main decision that needs to be made is whether the field is a legume field with some grass or a grass field with some legume. The economic cutoff for nitrogen fertilization is about 25 to 30 percent legume in the stand. At a greater percentage legume than this, it is probably best not to apply nitrogen. The main problem with adding nitrogen to a mixed stand is that the grass will become more competitive and further reduce the legume in the stand. However, if it is the last year that a stand will be maintained, adding nitrogen will probably be beneficial for that year. When the percentage of legume in the stand is below 25 to 30 percent, the field should be considered a grass field and nitrogen fertilizer or manure should be applied accordingly.