I just got this note from the Michigan Turfgrass Association:
Good news! The anticipated January thaw occurred in December! Anyway, the snow and ice melted giving the turf a chance to “breathe.” There is no concern at the current time about the annual bluegrass being under ice for 60 days. New ice did form in the low areas on greens and fairways on December 31, so we can start a new countdown for those areas from this date; however, it would be a good time to remove the ice from these small areas, at least on the greens, while the temperatures are still below freezing. I do not think we will have any more concern about new ice that may form on the greens later this month since they will not be under the ice for 60 days. Our next problem will be when the temperatures warm up around March and the annual bluegrass loses its cold temperature proteins and begins to take water into the crowns. If this occurs, severe annual bluegrass loss may occur in areas where standing water refreezes at night.
Dr. Joe Vargas