Golfdom, February 2019

TIMELY TURF ADVICE by Clark Talks Turf Spring dead spot it returns S uperintendents managing bermudagrass in the Transition Zone and in the northern part of the warm season turfgrass zone are awaiting an unfortunate annual event How much of their bermudagrass will be affected by spring dead spot Spring 2018 brought bad news for many superintendents in the form of considerable damage from spring dead spot What 2019 brings in the form of spring dead spot damage is anyones guess There is no good way to predict how much spring dead spot damage will occur over the winter although experience has shown that golf courses with bermudagrass located in the most northern locations often have the most spring dead spot damage The most common fungal species that cause spring dead spot are Ophiosphaerella korrae and O herpotricha Both are active in fall and infect roots rhizomes and stolons when soil temperature is 50 degrees to 70 degrees F The fungi do not cause the bermudagrass to die but rather weaken it Cold winter temperatures cause the turf to die The extent of spring dead spot damage is due to a combination of the extent of fungal infection in fall and the duration and magnitude of cold temperatures in winter Complicating our understanding of control and management of spring dead spot is the fact that O korrae and O herpotricha respond differently to nitrogen source and soil pH have different geographic ranges but may overlap in some locations and cause different degrees of spring dead spot damage The only way to know the extent of spring dead spot damage is to wait until the bermudagrass greens up in spring Areas damaged by spring dead spot will remain brown and the roots rhizomes and stolons of damaged plants will be dark brown to black Spring dead spot is most common on intensely managed bermudagrass stands Once spring dead spot occurs it will be found on the same locations 40 Golfdom February 2019 Golfdom com