Necrotic ring spot is a disease that can affect Kentucky bluegrass. Previously called Fusarium Bright, this group of diseases had the common symptom called 'frog-eye', or dead patch symptom. The prevalence of this disease increased in the 1960s when new variations of Kentucky bluegrass were introduced. The fungi are most the most active in spring and the second round of infection can be seen in the fall months. Control actions for this disease include: promoting plant growth in spring and fall, encourage deep rooting, oversees, and control thatch.