From what I've seen and heard, spring dead spot is particularly severe this year, which isn't a surprise given the cold winter with alternating wet and dry periods. These types of conditions are ideal for spring dead spot.
Unfortunately, there is nothing you can do in the spring to control spring dead spot. The pathogen does its damage in the fall and early winter, which causes the turf to be more susceptible to freezing injury. Even though you see the symptoms now, the disease isn't actively developing at this time.
The best you can do is to take steps to speed the bermudagrass recovery from the spring dead spot symptoms. Recovery from spring dead spot occurs primarily through the spread of stolons into the patch from the outside. There are several ways this can be accelerated:
1. Avoid use of DNA herbicides, like prodiamine, for pre-emergence control of crabgrass and other annual grasses. These herbicides inhibit turf root growth and will prevent the bermudagrass stolons from rooting as they spread into the patch from the outside. Oxadiazon is recommended instead because it does not inhibit root growth.
2. Break up the layer of dead turf in the spring dead spot patches through spiking or hollow-tine aerification. Roots emerging from the bermudagrass stolons cannot penetrate through this layer of dead turf to reach the soil below. Just like a grow-in situation, you need to establish good stolon-soil contact.
3. Apply fertilizer and irrigation in light and frequent doses, again mimicking a grow-in situation, to encourage growth of the poorly-rooted stolons. Note that the total amount of fertilization should not be increased, as any excess residual nitrogen remaining in the fall could exacerbate the disease.
For more information about spring dead spot, please see our spring dead spot disease profile.
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