The Royal Horticultural Society explains: "Apple canker is a disease caused by a fungus, Neonectria ditissima, which attacks the bark of apples and some other trees, causing a sunken area of dead ...

"Apple canker is a disease caused by a fungus, Neonectria ditissima, which attacks thebark of apples and some other trees, causing a sunken area of dead bark and, eventually, death of the branch.

Apple orchards throughout the Northeast witnessed a spate of rapid apple-tree decline (RAtD) in the past few years. It was ...