Nectria Twig Blight of Apple
Nectria twig blight, caused by the fungus Nectria cinnabarina, is a minor disease that breaks out occasionally. Because its symptoms are similar to those of fire blight, growers need to be able to recognize it. The chemical controls used for fire blight would be wasted on Nectria twig blight.
In early summer, leaves and shoots of infected twigs wilt and turn brown. Close examination will show that a canker has girdled the twig at the point where shoots begin to grow. Most often, this spot is located at the base of the previous season's cluster bud. Rome Beauty and close relatives such as Gallia Beauty, characterized by enlarged cluster-bud bases, are very susceptible. In midsummer, a few pink or coral fruiting structures of the fungus might appear in the cankered area.
No control is necessary.